ABSTRACT 
 
 
 
 
Title of Document: SYNTHESIS OF ZEOLITE@MOF 
NANOPOROUS COMPOSITES AS 
BIFUNCTIONAL CATALYSTS   
  
 Guanghui Zhu, Master of Science, 2014 
  
Directed By: Professor, Dr. Dongxia Liu, Department of 
Chemical and Biomolecular Engineering 
And 
Professor, Dr. Kyu Yong Choi, Department of 
Chemical and Biomolecular Engineering 
 
 
As nanoporous materials, zeolite and metal organic framework (MOF) share common 
characteristics of high surface areas and uniform micropores and differ in 
thermal/mechanical stability and structural flexibility. The integration of MOF and 
zeolite into composite particles is expected to produce useful hybrid nanoporous 
materials where inorganic zeolite and organic MOF components impart the advantages 
of high thermal, mechanical and structural stability of zeolites and specific 
functionality and high flexibility of MOFs. This thesis work addresses the synthesis of 
zeolite@MOF composites and the exploration of their applications as bifunctional 
catalysts in one-pot cascade reaction. Zeolite@MOF core-shell composites have been 
synthesized by solvothermal growth of MOFs on the surface of ZSM-5 particles. The 
acidity from framework Al-O(H)-Si sites in ZSM-5 and basicity from amine groups in 
  
 
MOFs obtained by pre-/post-synthetic modification endow zeolite@MOF composites 
bifunctionality in two-step cascade catalytic reactions. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
SYNTHESIS OF  ZEOLITE@MOF NANOPOROUS COMPOSITES AS 
BIFUNCTIONAL CATALYSTS 
 
 
 
By 
 
 
Guanghui Zhu 
 
 
 
 
 
Thesis submitted to the Faculty of the Graduate School of the  
University of Maryland, College Park, in partial fulfillment 
of the requirements for the degree of 
Master of Science 
2014 
 
 
 
 
 
 
 
 
 
 
Advisory Committee: 
Professor Dongxia Liu, Chair 
Professor Kyu Yong Choi 
Professor Michael R. Zachariah 
 
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
© Copyright by 
Guanghui Zhu 
2014 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 ii 
 
Dedication 
This work is dedicated to my parents, Honghua Zhu and Xuerong Geng, who 
have supported and encouraged me during my graduate study. Without them I cannot 
finish this Master’s degree. This work is also dedicated to my fiancée, Xueting Wang, 
for everything she have done including doing nothing but missing me 4000 miles away. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 iii 
 
Acknowledgements 
I want to give my thanks to my advisor, Dr. Dongxia Liu, for her guidance and 
instructions during my graduate study and research in her group. She worked diligently 
to help me with my research project and writing this thesis. I also thank her for her 
sound recommendation in my PhD applications which gave me the chance to pursue a 
higher education. I also want to thank my co-advisor Dr. Kyu Yong Choi, for his wise 
advice and encouragement during writing of the thesis. 
Thank you Dr. Dongxia Liu, Dr. Kyu Yong Choi, and Dr. Michael Zachariah 
for agreeing to serve on my committee. 
I would like to thank my labmates for their guidance and assistance during my 
1 year stay in Dr. Liu’s lab. I want to thank Laleh Emdadi for her expertise in zeolite 
synthesis and her assistance in using scanning and transmission electron microscopy. I 
want to thank Yiqing Wu for sharing his catalyst characterization knowledge. I want to 
thank Baoyu Liu for sharing his material simulation knowledge. 
I would like to thank Dr. Dongxia Liu, Christina Fontanos, Su Cheun Oh, 
Fudong Han and Xueting Wang for their help in reading and editing this thesis. 
At last, I want to thank all my fellow graduate students and friends for making 
my stay here meaningful and memorable. 
 iv 
 
Table of Contents 
 
Dedication ..................................................................................................................... ii 
Acknowledgements ...................................................................................................... iii 
Table of Contents ......................................................................................................... iv 
List of Tables .............................................................................................................. vii 
List of Figures ............................................................................................................ viii 
Chapter 1: Introduction ................................................................................................. 1 
1.1 Background on Nanoporous Materials ............................................................... 1 
1.2 Zeolite Materials ................................................................................................. 1 
1.2.1 Zeolite Structure and Nomenclature ............................................................ 2 
1.2.2 Synthesis of zeolites ..................................................................................... 5 
1.2.3 Applications of zeolites ................................................................................ 7 
1.3 MOF Nanoporous Materials ............................................................................... 9 
1.3.1 MOF structures .......................................................................................... 10 
1.3.2 Synthesis of MOFs ..................................................................................... 11 
1.3.3 Functionalization of MOFs ........................................................................ 13 
1.3.4 Application of MOF Materials ................................................................... 14 
1.3.5 MOF-based Core-Shell Composites .......................................................... 15 
1.4 Motivation and Thesis Outlines ........................................................................ 17 
Chapter 2: Synthesis and Postsynthetic Modification of ZSM-5@UiO-66 Core-Shell 
Particles as Bifunctional Catalysts .............................................................................. 19 
2.1 Introduction ....................................................................................................... 19 
 v 
 
2.2 Experimental ..................................................................................................... 22 
2.2.1 Materials .................................................................................................... 22 
2.2.2 Synthesis of ZSM-5 ................................................................................... 22 
2.2.3 Synthesis of UiO-66 and ZSM-5@UiO-66 ............................................... 23 
2.2.4 Incorporation of amine (−NH2) groups into ZSM-5@UiO-66 .................. 23 
2.2.5 Product characterizations ........................................................................... 24 
2.2.6 Catalytic reaction over ZSM-5@UiO-66 composite ................................. 25 
2.3 Results and Discussion ..................................................................................... 27 
2.4 Conclusions ....................................................................................................... 53 
Chapter 3: Synthesis and Presynthetic Modification of ZSM-5@UiO-66 Core-Shell 
Particles as Bifunctional Catalysts .............................................................................. 55 
3.1 Introduction ....................................................................................................... 55 
3.2 Experimental Part.............................................................................................. 56 
3.2.1 Materials .................................................................................................... 56 
3.2.2 Synthesis of UiO-66-NH2 and ZSM-5@UiO-66-NH2 .............................. 56 
3.2.3 Activation of the catalyst ........................................................................... 57 
3.2.4 Product characterizations ........................................................................... 57 
3.2.5 Catalytic reaction test over ZSM-5@UiO-66-NH2 composite................... 58 
3.3 Results and Discussion ..................................................................................... 58 
3.4 Conclusions ....................................................................................................... 67 
Chapter 4: Synthesis of ZSM-5@MIL-101 Core-Shell Particles as Bifunctional 
Catalysts ...................................................................................................................... 68 
4.1 Introduction ....................................................................................................... 68 
 vi 
 
4.2 Experimental ..................................................................................................... 68 
4.2.1 Materials .................................................................................................... 68 
4.2.2 Synthesis of MIL-101 and ZSM-5@MIL-101 .......................................... 69 
4.2.3 Incorporation of amine (−NH2) groups into ZSM-5@MIL-101 composite
............................................................................................................................. 69 
4.2.4 Acid Exchange Activation ......................................................................... 70 
4.2.5 Product characterizations ........................................................................... 70 
4.2.6 Catalytic reaction test over ZSM-5@MIL-101 composite ........................ 71 
4.3 Results and Discussion ..................................................................................... 71 
4.4 Conclusions ....................................................................................................... 75 
Chapter 5: Conclusions and Future Work ................................................................... 77 
5.1 Conclusions ....................................................................................................... 77 
5.2 Future Work ...................................................................................................... 78 
5.2.1 Mechanism investigation on growth of MOFs on zeolite surface ............. 78 
5.2.2 Optimization the functionalization process of zeolite@MOF composites 78 
5.2.3 Shape selectivity of zeolite@MOF composites in other applications ....... 79 
References ................................................................................................................... 80 
  
 vii 
 
List of Tables 
Table 1-1.  Chemical sources and their functions in zeolite synthesis.  
Table 1-2.  Commercial processes using zeolite catalysts. 
Table 1-3. List of most studied MOF structures and their properties. 
Table 1-4. Recent studies on MOF-based core-shell composites and their applications. 
Table 2-1.  Textural properties of UiO-66, ZSM-5, ZSM-5@UiO-66, ED-ZSM-
5@UiO-66, and HCl- ED-ZSM-5@UiO-66, derived from N2 and Ar isotherms. 
Table 2-2. Catalytic Reaction Results Summary. 
 
 
 
 
 
 
 viii 
 
List of Figures 
Figure 1-1. Primary building units, secondary building units, and three dimensional 
structures of zeolites. 
Figure 1-2. The secondary units (SBUs) recognized in zeolite frameworks. (a) Single 
four rings (S4R), (b) single six rings (S6R), (c) single eight rings (S8R), (d) double 
four rings (D4R), (e) single six rings (D6R), (f) four five rings, (g) pentasil unit, and 
(h) sodalite unit, respectively. 
Figure 1-3. Zeolite framework types: (A) FAU, (B) MOR, (C) MFI, (D) SOD, and 
(E) LTA, respectively. 
Figure 1-4. Active acid sites in zeolite framework. The bridging hydroxyl group in 
the structure is Brønsted acid site. 
Figure 1-5. Transition state shape selectivity of 1,2,4-trimethylbenzene production 
from m-xylene. 
Figure 1-6. Organic linkers commonly used in building MOF structures. 
Figure 2-1. Calibration curves of benzaldehyde dimethyl acetal, malononitrile, 
benzaldehyde and benzylidene malononitrile. 
Figure 2-2. SEM images of (A) ZSM-5 zeolite, (B) UiO-66 MOF, and TEM images 
of (C) ZSM-5,  (D), (E) and (F) ZSM-5@UiO-66. 
Figure 2-3. XRD patterns of (a) ZSM-5, (b) UiO-66, (c) ZSM-5@UiO-66, and (d) 
ED-ZSM-5@UiO-66. 
Figure 2-4. EDX spectra of as-synthesized (A) ZSM-5 zeolite and (B) ZSM-5@UiO-
66 core-shell composite. 
Figure 2-5. N2 adsorption-desorption isotherms of UiO-66, ZSM-5, ZSM-5@UiO-
66, ED-ZSM-5@UiO-66, and HCl-ED-ZSM-5@UiO-66, respectively. 
Figure 2-6. Ar adsorption-desorption isotherms (A), and the corresponding pore size 
distributions (B) derived from Ar sorption (NLDFT on the adsorption branch on the 
basis of spherical/cylindrical pore model) and (C) NLDFT on the adsorption branch 
on the basis of cylindrical pore model, of as-synthesized UiO-66, ZSM-5, ZSM-
5@UiO-66, ED-ZSM-5@UiO-66, and HCl- ED-ZSM-5@UiO-66, respectively. 
Figure 2-7. FTIR spectra of UiO-66, ZSM-5, ZSM-5@UiO-66, ED-ZSM-5@UiO-
66, and HCl-ED-ZSM-5@UiO-66, respectively. 
Figure 2-8. TGA curves of ZSM-5, UiO-66, ZSM-5@UiO-66 and HCl-ED-ZSM-
5@UiO-66, respectively. 
Figure 2-9. SEM images of (A) (B) ZSM-5 and ZSM-5@UiO-66 with SAR=∞, (C) 
(D) ZSM-5 and ZSM-5@UiO-66 with SAR=100, (E) (F) ZSM-5 and ZSM-5@UiO-
66 with SAR=40. 
Figure 2-10. Catalytic reaction results of as-synthesized ZSM-5@UiO-66 composite 
evacuated at 423 K. Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde 
and benzylidene malononitrile versus reaction time. 
Figure 2-11. Catalytic reaction results of ED-ZSM-5@UiO-66 composite treated 
with 1 M NH4NO3 water solution, evacuated at 343 K. Molar fraction of 
benzaldehyde dimethyl acetal, benzaldehyde and benzylidene malononitrile versus 
reaction time. 
Figure 2-12. Catalytic reaction results of ED-ZSM-5@UiO-66 composite treated 
with HCl ethanol solution, evacuated at (A) 343 K, (B) 423 K, (C) 473 K.  
 ix 
 
Figure 2-13. A comparison of benzaldehyde dimethyl acetal conversion, 
benzaldehyde yield, benzylidene malononitrile yield and selectivity, rate constant of 
the composite treated with HCl ethanol solution and evacuated at 343 K, 423 K and 
473 K. 
Figure 2-14. Catalytic reaction results of HCl-ED-ZSM-5@UiO-66 composite. 
Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde and benzylidene 
malononitrile versus reaction time. 
Figure 2-15. Catalytic reaction results of (A) ZSM-5, (B) ED-ZSM-5, (C) HCl-ED-
ZSM-5. Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde and 
benzylidene malononitrile versus reaction time. 
Figure 2-16. Catalytic reaction results of HCl-ED-UiO-66. Molar fraction of 
benzaldehyde dimethyl acetal, benzaldehyde and benzylidene malononitrile versus 
reaction time. 
Figure 3-1. SEM images of (A) ZSM-5 zeolite, (B) (C) UiO-66 MOF, and (D) ZSM-
5@UiO-66-NH2. TEM images of (E) (F) ZSM-5@UiO-66. 
Figure 3-2. XRD patterns of (a) ZSM-5, (b) UiO-66-NH2 and (c) ZSM-5@UiO-66-
NH2, respectively. 
Figure 3-3. EDX spectra of as-synthesized (A) ZSM-5 zeolite and (B) ZSM-5@UiO-
66-NH2 core-shell composite. 
Figure 3-4. N2 adsorption-desorption isotherms of UiO-66-NH2, ZSM-5, and ZSM-
5@UiO-66-NH2, respectively. 
Figure 3-5. FTIR spectra of UiO-66-NH2, ZSM-5 and ZSM-5@UiO-66-NH2, 
respectively. 
Figure 3-6. Catalytic reaction results of as-synthesized ZSM-5@UiO-66-NH2 and 
acid-exchanged ZSM-5@UiO-66-NH2. Molar fraction of benzaldehyde dimethyl 
acetal, benzaldehyde and benzylidene malononitrile versus reaction time. 
Figure 4-1. SEM images of (A) commercial ZSM-5 zeolite, (B) MIL-101 MOF, and 
(C) ZSM-5@MIL-101. 
Figure 4-2. XRD patterns of (a) ZSM-5, (b) MIL-101 and (c) ZSM-5@MIL-101, 
respectively. 
Figure 4-3. N2 adsorption-desorption isotherms of MIL-101, ZSM-5, ZSM-5@MIL-
101, and ED-ZSM-5@MIL-101, respectively. 
Figure 4-4. Catalytic reaction results of ZSM-5@MIL-101. Molar fraction of 
benzaldehyde dimethyl acetal, benzaldehyde and benzylidene malononitrile versus 
reaction time. 
 
 
 1 
 
Chapter 1: Introduction 
1.1 Background on Nanoporous Materials 
Nanoporous materials are comprised of organic, inorganic, or organic-inorganic 
hybrid frameworks that support regular porous structures. The pore size in nanoporous 
materials is generally smaller than 100 nm. According to the International Union of 
Pure and Applied Chemistry (IUPAC),[1] the nanoporous materials can be categorized 
into three classes: microporous materials of 0.2 – 2 nm in pore size, mesoporous 
materials of 2 – 50 nm in pore size, and macroporous materials of 50 – 1000 nm in pore 
size. High specific surface area, large pore volume and uniform pore size are 
characteristics of nanoporous materials, which endow them superior performances in 
adsorption, separation and catalysis applications in comparison with their solid 
counterparts.[2, 3] Zeolites and metal organic frameworks (MOFs) are two important 
examples of nanoporous materials, being intensively studied for many applications.[4-
7] 
1.2 Zeolite Materials 
Zeolites are microporous aluminosilicates whose basic units are TO4 
tetrahedrons (T: Tetrahedrally coordinated atoms, e.g. [SiO4] or [AlO4]-).[8] The 
discovery and use of zeolite can be tracked back to 1756 by Swedish mineralogist 
Cronstedt.[9] Since then, the natural zeolites have been discovered and known for 
adsorption and ion-exchange applications. In 1980’s, the development of petroleum 
industry inspired an explosion on synthetic zeolites.[10] In the last couple of decades, 
numerous publications and patents have reported advances in new synthetic approaches 
 2 
 
to produce zeolites with new structures and applications of zeolite membranes in 
separations.[11] Today, zeolite science is active in engineering hierarchical zeolites 
with desirable meso- and microporous topologies for bulky molecules involved 
separation or catalysis applications.[12, 13] Synthesis of ultra-thin such as unit-cell 
thick zeolites is an emerging area with promising applications as thin membranes for 
desirable separations.[14] 
1.2.1 Zeolite Structure and Nomenclature 
The basic TO4 tetrahedrons in zeolite are called primary building units, which 
are connected alternatively by sharing oxygen atoms as bridges to form secondary 
building units such as rings or other complex blocks, as shown in Figure 1-1. The 
secondary building unit may contain four, five, six, or more atoms in each ring, as 
illustrated in Figure 1-2. Each apex stands for a tetrahedron and the lines between 
apexes are oxygen bridges. The assembly of the secondary building units generates 
three dimensional zeolite structures. The connectivity (topology) of the tetrahedral 
atoms in three dimensional zeolites defines the zeolite framework type and determines 
the size and shape of the pores and the channel systems in zeolites. Each framework 
topology is assigned a three capital letter code by the Structure Commission of the 
International Zeolite Association (IZA).[15] A collection of nomenclature for zeolites 
is also available on the IZA’s website (http://www.iza-synthesis.org/).  
 3 
 
 
Figure 1-1. Primary building units, secondary building units, and three dimensional 
structures of zeolites. 
 
Figure 1-2. The secondary units (SBUs) recognized in zeolite frameworks. (a) Single 
four rings (S4R), (b) single six rings (S6R), (c) single eight rings (S8R), (d) double four 
rings (D4R), (e) double six rings (D6R), (f) four five rings, (g) pentasil unit, and (h) 
sodalite unit, respectively.[16] 
 
 According to IZA publications, there are around 206 zeolite framework 
types.[15] The most commonly studied zeoltie framework types are FAU (Faujasite), 
MOR (Mordenite), MFI (ZSM-5(FIVE)), SOD (Sodalite) and LTA (Linde Type A) 
 4 
 
zeolites. Below is a brief description for topological structures of these five zeolites. 
Figure 1-3 demonstrates the corresponding cage and/or channel structures of these 
zeolites. 
FAU-type zeolite (Figure 1-3 (A)) has SOD cages joined by double 6 rings in 
the same way as diamond. This creates a 12-membered ring and a 3-dimensional 
channel system. FAU belongs to large-pore zeolites, widely used as catalysts for fluid 
catalytic cracking of heavy compounds in petroleum refinery.[17, 18] MOR-type 
zeolite (Figure 1-3 (B)) is built on 5-ring units. Four 5-rings are interconnected by 
oxygen bridges. Mirror images of the 5-ring chains are connected to form sheets. The 
sheets are connected to one another to form adjacent 12- and 8-membered ring one 
dimensional channels along the z-axis. MFI (example: Zeolite Socony Mobil-5 (ZSM-
5)) type is constructed by pentasil units (see Figure 1-2 (g)). Several pentasil units are 
linked together by oxygen bridges to form pentasil chains, which are interconnected by 
oxygen bridges to form corrugated sheets with 10-ring holes. A stack of sheets are 
connected by oxygen bridges to form a structure with straight and zig-zag 10-
membered ring channels parallel and perpendicular to the sheets (Figure 1-3 (C)). The 
latter zig-zag channels in the x-direction link the straight channels to form a 3-
dimensional 10-membered ring channel system. The pore opening is slightly smaller 
than the 12-membered ring in FAU, which is classified as medium pore zeolites.[19, 
20] SOD (example: sodalite) type zeolite has a body-centered cubic arrangement of 
sodalite units (Figure 1-3 (D)). It has small pore openings of the 6-membered ring 
windows, which limit the application capacity of sodalite cavities inside. It is an 
important material as a host of advanced materials.[21] LTA (example: Linde Type A) 
 5 
 
type is a structure in which SOD cages are connected by double 4-ring units in a cubic 
arrangement (Figure 1-3 (E)). This creates an 8-membered ring in the center of 4 
sodalite cages, giving a larger pore opening than sodalite. Zeolite A is used as desiccant 
and ion-exchanger in laundry detergents.[22] 
 
Figure 1-3. Zeolite framework types: (A) FAU, (B) MOR, (C) MFI, (D) SOD, and (E) 
LTA, respectively.[15] 
 
1.2.2 Synthesis of zeolites 
 Natural zeolites are formed under volcanic conditions with extremely long 
reaction times.[23] The early work in synthesizing zeolites mimicked the high 
temperature and salt concentrations found in nature. Since 1946, many zeolite types 
without a natural counterpart have been synthesized.[24] Hydrothermal synthesis is 
the conventional method used for generating zeolite materials. The general synthetic 
procedure is illustrated in the flow chart of Scheme 1-1. The first two steps in the 
scheme can be summarized as the preparation of the zeolite synthetic gel, which is the 
 6 
 
most time-consuming step in the whole process. The composition of the synthetic gel 
determines the zeolite structure to be produced. Crystallization is the third step in the 
process, which is usually carried out in an autoclave that is held in a preheated oven for 
a period of time ranging from a few minutes to weeks. The temperature and duration 
of crystallization affects the size and morphology of the zeolite. The isolation of zeolite 
can be done by centrifugation or flocculation, which is the last step in the process. 
 
Scheme 1-1. General procedure for synthesis of zeolite. 
 The chemical sources and their functions in the synthesis of zeolites are listed 
in Table 1-1. Inorganic silicon sources include soluble silicates and silica sols that are 
made from fumed silica. Organic silicon sources such as tetraethyl orthosilicate 
(TEOS) and silicic acid are also widely used in the synthesis. It has been reported that 
different silicon sources influence the ageing time for gelation of the zeolite synthetic 
precursors.[25] Sodium aluminate, aluminum hydroxide (Al(OH)3), aluminum 
alkoxide and aluminum sulfate etc. are commonly used as aluminum sources in the 
zeolite synthesis. The optimal pH range for zeolite synthesis is 11-13[26], which can 
be modulated by the addition of OH- guest molecules. Organic templates are used 
extensively as structure directing agents (SDAs) for certain types of zeolite structures. 
To avoid the toxicity and high cost of SDAs, template-free syntheses of zeolites are 
drawing a lot of research interest in commercial production of zeolite materials.[27, 28] 
 
 
 7 
 
Table 1-1.  Chemical sources and their functions in zeolite synthesis. 
Sources Functions 
SiO2 Primary building units 
AlO2- Origin of framework charge 
OH- Mineralizer 
Alkali cation, template Counterion of AlO2- 
Water Solvent 
 
 Hydrothermal crystallization is the conventional method used in the synthesis 
of zeolites. The required synthesis temperature and pressure depends on the zeolite 
type. Most commercial zeolites are synthesized at 363-373 K, but some dense zeolites 
need higher crystallization temperatures (up to 623 K). The ageing time is important in 
that a certain induction period is needed at ambient temperature before the 
crystallization take place. It has to be noted that different reaction times will sometimes 
result in different zeolite structures. This is because all zeolites are metastable species 
and they will convert to denser structures over time. Aside from the conventional 
hydrothermal method, microwave-mediated synthesis has been applied to the synthesis 
and modification of zeolites.[29] In microwave-assisted synthesis, the heating comes 
from the interactions between polar molecules and the electromagnetic field. Rapid 
crystallization of zeolite is achieved in microwave-assisted synthesis in comparison 
with hydrothermal synthesis as a result of high rates of temperature rise and different 
heating mechanisms.[30] 
1.2.3 Applications of zeolites 
The periodic channel systems and crystalline structure makes zeolites 
physically and chemically stable compounds that can be widely used in gas storage, 
separation and heterogeneous catalysis. For the gas storage applications, the large void 
 8 
 
volume in the zeolite framework offers the storage capacities. When water molecules 
are removed from the framework, zeolites can take in other molecules. The adsorption 
and storage of hydrocarbons in zeolites has been studied intensively.[31-33] Zeolites 
possess a wide variety of internal channels and cavities accessed through oxygen 
windows which have sizes similar to the dimensions of common organic and inorganic 
molecules. This unique textural property endows zeolites with capabilities to separate 
mixtures of molecules with different sizes.  For example, FAU and ZSM-5 are widely 
used in separating C8 aromatics and alkane isomers.[34, 35] The extensive internal 
surface, variable pore sizes and ion-exchange properties make zeolites good candidates 
as catalysts for many catalytic reactions in industry. For example, zeolite has been used 
as acid catalysts petroleum refining processes, including catalytic cracking, 
hydrocracking, isomerization, alkylation and oligomerization.[23]  
The zeolite acidity in H+-form zeolites originates from framework Al species, 
as shown in Figure 1-4 (A).[36] The unique pore systems in zeolites only allow them 
to admit certain sized molecules to enter or reside in the framework, and thus offer 
zeolite unique shape selectivity in catalysis. One example of zeolite shape selectivity 
is the production of 1,2,4-trimethylbenzene from m-xylene. The transition state shown 
in Figure 1-4(B) in the upper channel cannot fit in the zeolite channel. This prevents 
the production of 1,3,5-trimethylbenzene and offers high selectivity for the 1,2,4-
trimethylbenzene molecules. 
 9 
 
 
Figure 1-4. (A) Active acid sites in zeolite framework. The bridging hydroxyl group 
in the structure is Brønsted acid site. (B) Transition state shape selectivity of 1,2,4-
trimethylbenzene production from m-xylene. (Reproduced from Reference [23]) 
 
1.3 MOF Nanoporous Materials 
Metal organic frameworks (MOFs) are a group of emerging nanoporous 
materials containing inorganic building bricks and organic linkers.[37, 38] This new 
class of nanoporous materials was first discovered by Bernard Hoskins and Richard 
Robson in 1989.[39] They proposed a prototype in which tetrahedral or octahedral 
arrays of valences are linked by rod-like molecular linkers, similar to the modern 
concept of MOF. The large size of cavities and opening windows were considered 
intriguing features of this new kind of material. These structures also drew interest from 
many other curious researchers in the past years.[40-45] Omar Yaghi is one of them 
who made the most impressive progress and popularized the name “metal organic 
frameworks”.[46-49] Yaghi and his coworkers developed thermally stable MOF 
structures capable of reversible guest molecule subtraction with permanent micropore 
systems.[49] This was a big breakthrough for MOFs towards various potential 
applications. Ever since the first several proof-of-concept practical MOF structures 
were discovered, a lot of thermal/chemical stable MOFs has been developed with high 
pore volume and surface area.[50] 
 10 
 
1.3.1 MOF structures 
It has been established that the structure of MOFs is constructed from metal-
containing units (SBUs) that act as lattice nodes and are held in place by multidentate 
organic linkers. Because a range of SBUs and organic linkers can be built into MOFs, 
a wide structural diversity and highly designable pore sizes and shapes in MOFs is 
expected.[38, 51] A collection of common linker structures are shown in Figure 1-6. 
Some of the most studied MOF structures and their topological and structural properties 
are summarized in Table 1-3. 
 
Figure 1-6. Organic linkers commonly used in building MOF structures. 
 
 
 
 
 
 
 
 
 11 
 
Table 1-3. List of most studied MOF structures and their properties. 
Nomenclature Chemical Formula Topological Properties Structural Properties 
MOF-5[52] Zn4O(BDC)3 
ZnO4 tetrahedra joined by 
benzene dicarboxylate linkers 
to give a cubic framework 
with interconnected pores of 8 
Å aperture width and 12 Å 
pore diameter. 
Exchangeable properties of 
guest molecules while 
maintaining its morphology 
and crystallinity. 
HKUST-1[53] Cu3(TMA)2(H2O)3 
Cu(II) paddlewheel dimers 
linked by trimesate trianions 
with 10 Å pore size. 
The water ligands in the 
structure can be removed It 
rehydrates when exposed to 
moisture. The metal ion in 
the cluster can be 
exchanged with oxophilic 
transition metals with 
higher stability. 
ZIFs[54, 55] Zn(im)2 
Composed of tetrahedrally-
coordinated transition metal 
ions (e.g. Fe, Co, Cu, Zn) 
connected by organic 
imidazole linkers. 
More than 100 topologies 
of ZIFs have been 
discovered[55]. The most 
studied ZIF-8, with a 
sodalite topology[56], has 
applications in CO2 capture 
and separation[57] and also 
in MOF composites. 
MIL-101[58, 
59] 
Cr3F(H2O)2O[(O2C
)-C6H4-(CO2)]3 
Linked by chromium trimers 
and terephthalate. The pore 
space is constructed from two 
cages with 
diameters of 2.9 and 3.4 nm 
which are connected with 
windows with diameters of 
1.2 and 1.45 nm. 
Thermally stable up to 773 
K with high surface area 
(~6000 m2 g-1). 
UiO-66[60] 
Zr3O2(OH)2(O2C-
C6H4-CO2)3 
Linked by zirconium trimers 
and terephthalate, leading to a 
3D arrangement of 
micropores in which each 
centric octahedral cage (free 
diameter: 11 Å) is connected 
to eight corner tetrahedral 
cages (free diameter 8 
Å)through triangular 
windows (6 A˚ ).  
Thermally stable up to 813 
K; Both metal clusters and 
organic linkers can be 
functionalized easily. 
1.3.2 Synthesis of MOFs 
 Since the discovery of MOF structures, research emphasis has been placed on 
synthesis of new MOF structures and better crystallinity/morphology control of 
existing MOFs. Until now, a number of conventional[61, 62] and novel synthesis 
methods have been developed. A description of these synthesis routes is listed below: 
 12 
 
(i) Conventional synthesis methods: Conventional synthesis methods usually 
refer to syntheses carried out using electric heating of the synthesis devices. Based on 
the temperature used in the synthesis, these synthesis methods are sub-classified into 
solvothermal synthesis and nonsolvothermal synthesis methods. Solvothermal 
synthesis requires closed vessels such as autoclaves to hold the MOF precursors at the 
temperatures higher than the solvent boiling point. Nonsolvothermal synthesis, on the 
contrary, is conducted at temperatures lower than or at the boiling point of the solvent. 
A precipitation reaction followed by recrystallization is common in nonsolvothermal 
synthesis.[39] ZIF-8[63] and HKUST-1[64], for example, are commonly synthesized 
at low temperatures using nonsolvothermal method. 
(ii) Novel synthesis methods: Novel synthesis methods use unconventional 
energy sources to produce MOFs, such as electrochemical energy,[65] microwave-
assisted heating,[66] mechanochemical energy,[67] and sonochemical energy.[68] 
Electrochemical synthesis of MOF was developed by BASF[65] in the path of 
commercializing MOF products. Their initial purpose was to exclude anions by using 
metal electrodes as metal sources. This method has been proved to be a potential 
candidate for industrial continuous synthesis of MOFs.[69, 70] Microwave-assisted 
synthesis is most widely used among the novel methods.[71] Like described in 
microwave synthesis of zeolites, this method allows for a faster crystallization rate and 
production of smaller MOF crystals.[66, 72] Mechanical force can also induce 
chemical reactions.[73] For example, stoichiometric amounts of metal salt and organic 
linkers can be mixed by liquid-assisted grinding or ion-assisted grinding to produce 
MOF crystals. This method shows a promising path in which no external heating or 
 13 
 
solvent is needed, and reduces the washing and activation labor after the synthesis. In 
sonochemical synthesis, ultrasound is applied to induce high temperature and pressure 
inside the system through the cavitation process. Chemical reactions can take place 
within the cavity, at the interface, or in the bulk media. Early works demonstrated MOF 
nanocrystals can be obtained by room temperature fast synthesis assisted by 
ultrasound.[68, 74] 
1.3.3 Functionalization of MOFs 
 The diversity of MOF structures creates a variety of functionalities and potential 
applications for the as-synthesized MOFs. Additionally, the components in MOFs, 
either metal clusters or organic linkers, can be further modified to bring in new 
functionalities. The methods for functionalization of MOFs include presynthetic 
modification, postsynthetic modification (PSM) and postsynthetic deprotection (PSD), 
respectively.  
The presynthetic modification requires the introduction of functional groups to 
the building blocks (most commonly functionalized linkers) prior to the synthesis. In 
this method, the synthetic conditions developed for the original MOFs may become 
inefficient because of the changes in chemical properties of linkers.[52, 75] Therefore, 
only a limited number of functional groups can be introduced into MOF frameworks. 
The postsynthetic modification of MOFs, however, circumvents problems in 
the presynthetic modification of MOFs. PSMs are heterogeneous processes in which 
the modifications are directly performed on the MOF frameworks via covalent PSM or 
dative PSM, on the basis of chemical bond type formed or broken in the process. This 
functionalization method has been widely reported by the work in Cohen’s group.[76-
 14 
 
79] A concern in this method is that the framework remains unimpaired during the 
process. 
PSD is a variant of PSM in which a protected functional group is introduced 
before the solvothermal reaction without interfering with the solvothermal conditions. 
Afterwards, the protecting groups are removed either in situ[80] or after synthesis[81] 
to recover the functional groups. 
1.3.4 Application of MOF Materials 
 As nanoporous materials, MOFs break the limitation of the small pore sizes of 
zeolites. They can be used for a number of potential applications, including gas 
separation, storage, and heterogeneous catalysis.[6, 7, 38, 62, 82-87] Below is a brief 
description for each type of applications. 
(i) Gas storage: The gas storage capability of MOFs originates from the large 
void volume in the framework. The first example in MOF storage showed a comparable 
CH4 adsorption capacity to that of zeolite and activated carbon.[88] To date, the highest 
CH4 uptake reported is 189 mg g-1 in Porous Coordination Network-14 (PCN-14) at 35 
bar and 290 K.[89] 
MOFs are also good storage materials for H2 at 77 K and moderate pressure 
(<100 bar) conditions,[62] however, the cryogenic and high pressure systems are 
usually not feasible for practical applications. To improve H2 loading capability of 
MOFs at low pressure, kinetic trapping mechanism can be used by creating modulated 
interactions and distances between MOF framework and adsorbate molecules entering 
the framework.[90] On the other hand, Pt particles loaded to the MOF framework will 
 15 
 
lead to H2 spillover effect,[91] which will improve H2 diffusion and make it possible 
to adsorb H2 at room temperature.  
(ii) Gas separation: MOFs have regulated and uniform pore systems and thus 
can be used in separation applications. For this application, MOFs are usually mixed 
with a substrate to improve permeability and stability of the MOF materials. For 
example, ZIF-8/Matrimid was prepared by a solution-blending approach and the as-
prepared membranes enhanced the transport of CO2 gas from CO2/CH4 gas 
mixtures.[92] Silica@MOF core-shell composite spheres were fabricated by the seeded 
growth method and the application of silica@MOF composite spheres as stationary 
phases for chromatographic separation.[93] 
 (iii) Catalysis: MOFs as catalysts can be synthesized or functionalized with 
active sites including unsaturated metal sites or functional groups on organic linkers. 
Synthesis of MOFs containing unsaturated metal sites requires the introduction of 
labile guest molecules that can be removed in the activation stage. MOFs with metal 
active sites have been used in catalytic reactions such as hydrogenation/ 
isomerization,[94, 95] cyanosilylation,[96] oxidation,[97, 98] photocatalysis,[99] etc. 
Organic functional groups are brought into the framework by either presynthetic 
modification or postsynthetic modification. MOFs with functional groups as active 
sites have been reported in Knoevenagel condensation,[100, 101] and also in 
transesterification,[102] polymerization[103] and aldol reactions.[104]  
1.3.5 MOF-based Core-Shell Composites 
In addition to tailoring frameworks for potential broad applications, synthesis 
of MOF-based composites is another approach to improve the functionalities and 
 16 
 
applications of MOFs. Generally, the composites are formed by physical or chemical 
mixing of MOFs with inorganic or organic materials, which allows easy modification 
of MOFs for practical subjects. The materials selected possess properties that are 
complementary with MOFs, resulting in combined merits coming from MOFs (high 
surface area, tunable pore size and functionality) and functional materials (mechanical, 
electrical, magnetic and catalytic properties). Up to now, MOF composites have been 
built successfully with metal,[105] oxides (metal oxides, silica),[106, 107] 
polymers,[84] carbons (CNTs, graphene)[108] and semiconductors,[109] etc. Table 1-
4 lists the recent studies on MOF-based core-shell composites.  
Table 1-4. Recent studies on MOF-based core-shell composites and their applications. 
Core-shell 
composite 
Synthesis method Applications Example materials 
Metal 
nanoparticles 
(MNPs)@MOF 
Grow MOFs around pre-synthesized 
MNPs. Surface modification to the 
MNPs is essential in some cases to 
facilitate MOF growth on the surface of 
MNPs 
Hydrogen 
storage,[110] 
heterogeneous 
catalysis[111] 
and sensing[112] 
Au/Ag/Pt 
NPs@ZIF-8.[113] 
Metal oxide 
nanoparticles 
@MOF 
Metal oxide NPs surface are decorated 
with analogs of MOF building blocks 
(functional groups with amine or 
carboxylic acid) to facilitate MOF 
growth. 
Magnetism[114] 
Fe2O3 NP@DUT-
4/DUT-5/HKUST-
1 [114] 
Silica@MOF Grow MOF on surface decorated SiO2. 
Drug 
delivery[115] 
SiO2@In(IPA)m[11
6]  
Polymer@MOF 
Grow MOF on surface-decorated 
polymer particles 
Catalysis, 
separations, gas 
storage 
Polystyrene@ZIF-
8[117] 
Quantum dots 
(QDs)@MOF 
The modification of QD surfaces can 
promote MOF formation around QDs 
photostability, 
fluorescent 
properties and 
quantum 
effects[118] 
CdTe@ZIF-8.[113] 
Carbon@MOF Grow MOF on graphene and CNTs. 
Hydrogen 
storage[108] 
CNT@MOF-
5[108] 
  
 17 
 
1.4 Motivation and Thesis Outlines 
Zeolites are traditional crystalline microporous aluminosilicates, while MOFs 
are an emerging class of nanoporous materials. The combination of zeolites and MOFs 
should be a very promising platform for advancing these two materials for various 
applications considering the well-developed catalytic applications of zeolites and the 
intriguing potential of MOFs. The synthesis of zeolite/MOF composites, however, has 
not been reported in literature. This thesis work aimed to explore the approaches to 
synthesize the composite materials and their applications as catalysts in cascade 
reactions. 
The integration of MOF and zeolite into composite materials especially core-
shell composites is the main objective of this thesis. Moreover, presynthetic and 
postsynthetic modification has been carried out to make the composites catalytic 
bifunctionality in two-step cascade reactions. Chapter 2 of this thesis reports the 
synthesis of ZSM-5@UiO-66, an example of zeolite/MOF core-shell composite, by 
sequential hydrothermal synthesis of ZSM-5 core and solvothermal growth of UiO-66 
on the zeolite support. The as-synthesized composite was modified by PSM to acquire 
acid-base bifunctionality for two step cascade reactions. Chapter 3 discusses the 
synthesis of ZSM-5@UiO-66 with 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC) 
linkers. By using the NH2-BDC linkers, amine groups were incorporated into the 
catalyst in MOF crystallization step. The bifunctionality in the ZSM-5@UiO-66-NH2 
synthesized by this approach was confirmed by the two-step cascade reactions used in 
Chapter 2. Chapter 4 summarizes the work on the synthesis of ZSM5@MIL-101 
nanoporous composites. The replacement of UIO-66 with MIL-101 in the composites 
 18 
 
indicates that the synthetic methodology developed in this thesis is applicable to 
produce other types of zeolite@MOF composites. Chapter 5 summaries the 
conclusions of this thesis work with proposed future research as extensions of this 
work. 
  
 19 
 
Chapter 2: Synthesis and Postsynthetic Modification of ZSM-
5@UiO-66 Core-Shell Particles as Bifunctional Catalysts 
2.1 Introduction 
Metal-organic frameworks (MOFs) are an emerging class of crystalline 
microporous materials. The uniform micropores and high surface areas enable them a 
number of potential applications, including separation, storage, and heterogeneous 
catalysis.[6, 7, 38, 62] The structure of MOFs is constructed by metal ions or clusters 
that act as lattice nodes and are held in place by multidentate organic ligands. Since a 
range of metal clusters and organic ligands can be built into MOFs, a wide structural 
diversity and highly designable pore sizes and shapes in MOFs are expected, which 
endow MOFs with tunable cavity architectures and properties.[37] Furthermore, the 
primary framework of MOFs can be functionalized through pre- or post-synthetic 
modification of metal clusters and/or organic ligands, and thus offers the possibility for 
fine-tuning their pore dimensions and local environment inside the micropores.[79] 
The great tunability in structures and functional properties of MOFs allows potential 
implementation of MOFs into technical materials for practical applications.  
In addition to tailoring the structure of MOFs, synthesis of MOF-based 
composites is another approach to advance their functionalities for practical 
applications.[119] MOF-based composites are generally formed by physical or 
chemical mixing of MOFs with inorganic and/or organic substrates that allows an easy 
modification of MOFs for practical applications. Recently, MOF-based composite 
membranes and spherical solids have been prepared for direct uses in gas or liquid 
 20 
 
separations and as catalysts in heterogeneous catalytic reactions. For example ZIF-
8/Matrimid were prepared by a solution blending approach and the as-prepared 
membranes have been found to enhance the transport of CO2 gas from the CO2/CH4 
gas mixtures;[92] Uniform coating of Cr-MIL-101 inside the macropores of a 
cylindrical cordierite monolith was achieved by the secondary growth technique and 
the composite was used as stable catalyst in liquid-phase oxidation reactions;[120] 
Silica@MOF core-shell composite spheres were fabricated by the seeded growth 
method and they were used as stationery phases for chromatographic separation to 
overcome the problems such as low column efficiency, high column back pressure, and 
undesirable peak shapes caused by the direct packing of MOF particles of irregular 
shapes.[93] These studies illustrate the recent research efforts in advancing MOF-based 
composites into technical materials for practical applications. 
In this study, we report the synthesis of zeolite@MOF core-shell structured 
composites by solvothermal growth of MOF on the surface of zeolite support and 
demonstrate an application of this material as a bifunctional acid-base catalyst in two-
step cascade reactions. Zeolites are crystalline microporous aluminosilicates, widely 
used as heterogeneous catalysts, adsorbents, and ion-exchange materials in 
petrochemical and fine chemical industries.[8, 121-123] As porous materials, zeolite 
and MOF share common characteristics of high surface areas and uniform micropores 
but they differ in thermal/mechanical stability and structural flexibility.[124] In this 
context, the zeolite@MOF composites are expected to be a novel and useful porous 
system where inorganic zeolite and organic MOF components impart the advantages 
of higher thermal, mechanical and structural stability of zeolites and specific 
 21 
 
functionality and high flexibility of MOFs for a variety of applications. To our 
knowledge, however, the integration of MOF and zeolite into core-shell structured 
composites has not been reported in literature. 
In this chapter, the synthesis of ZSM-5@UiO-66 core-shell structured 
composites and demonstration of this material as a bifunctional acid-base catalyst in 
two-step cascade reactions is reported. ZSM-5 is a medium pore zeolite with a pore 
system consisting of two types of intersecting straight and zig-zag 10 member ring 
channels, which is widely studied as membrane materials in xylene separation and 
catalysts in petroleum refinery.[125-127] 
UiO-66 is Zr-containing MOF composed of hexameric Zr6O32 units linked by 
benzenedicarboxylate (BDC) linkers and has excellent stabilities not typically found in 
common porous MOFs.[60] The ZSM-5@UiO-66 composite is a promising chemical 
and thermal stable material with a wide range of applications. A schematic illustration 
of the functional composite is shown in Scheme 2-1. 
 
Scheme 2-1. Schematic illustration of the functional composite with acid and base 
catalytic sites in zeolite and MOF framework, respectively. 
 
 22 
 
2.2 Experimental 
2.2.1 Materials 
 Tetrapropylammonium hydroxide (TPAOH, 40% in aqueous solution), 
tetraethylorthosilicate (TEOS, 98%), aluminum isopropoxide (99.99%), ZrCl4 (99.9%) 
and 1,4-benzene-dicarboxylate (BDC, 98%) were purchased from Alfa Aesar. NaOH 
(97%), ethylene diamine (ED, 99.5%) and malononitrile (99%) were purchased from 
Sigma-Aldrich. Dimethylformamide (DMF, 99.8%) and anhydrous toluene (99.5%) 
were purchased from BDH. Hydrochloric acid (36.5%-38.0%) was purchased from JT 
Baker. Acetonitrile (99.9%) was purchased from Fisher. Benzaldehyde dimethyl acetal 
(98%) was purchased from SAFC. All chemicals were used as received without further 
treatment. Deionized (DI) water was used in all purpose. 
2.2.2 Synthesis of ZSM-5 
Zeolite ZSM-5 was hydrothermally synthesized by using the recipe with a 
composition of 100SiO2:0.5Al2O3:1NaOH:36TPAOH:4000H2O. Typically, 0.0111 g 
NaOH and 5.075 g TPAOH solution were added to 20 g DI water. Subsequently, 
0.0564 g aluminum isopropoxide and 5.78 g TEOS were added to the solution. The as-
prepared mixture was stirred vigorously at room temperature for 8 h, followed by 5 
days in tumbling Teflon-lined steel autoclaves at 423 K. The product was collected by 
centrifugation and washed repeatedly with DI water to reduce pH to ~ 9. Afterwards, 
the product was dried at 343 K and calcined at 873 K under flowing air (150 mL min-
1) for 6 h. The as-synthesized ZSM-5 was ion exchanged three times using 1 mol L-1 
aqueous NH4NO3 solution at 353 K for 2 h, and subsequently, collected by 
 23 
 
centrifugation, washed with DI water for three times, and dried at 343 K overnight.  
The zeolite sample in its NH4+-form was treated in flowing air (150 mL min-1) by 
increasing the temperature from ambient to 823 K at 1.5 K s-1 and holding for 4 h to 
thermally decompose to NH3 and H+.  
2.2.3 Synthesis of UiO-66 and ZSM-5@UiO-66 
The synthesis of UiO-66 particles was carried out as follows: 0.106 g ZrCl4 and 
0.068 g BDC were dissolved in 24.9 g DMF in sequence. The solution was transferred 
to a Teflon-lined stainless steel autoclave and allowed to react at 393 K for 24 h. The 
product was collected by centrifugation and washed by dispersing in DMF for 12 h 
under rigorous magnetic stirring. The DMF washing and centrifugation steps were 
repeated three times. Afterwards, the sample was dispersed in methanol solvent for 12 
h followed by centrifugation in order to remove the DMF solvent. This step was 
repeated two times. Finally, the sample was dried in a vacuum oven at 423 K overnight. 
The synthesis of ZSM-5@UiO-66 core-shell composite was performed with the same 
procedure as described above except that 0.15 g ZSM-5 particles were added to the 
UiO-66 synthetic solution prior to the solvothermal crystallization of MOF particles. 
2.2.4 Incorporation of amine (−NH2) groups into ZSM-5@UiO-66  
The incorporation of amine groups into the composite was performed in a 150 
mL flask equipped with a reflux condenser and heated in a temperature controlled oil 
bath under atmospheric pressure and magnetic stirring (500 rpm) conditions. Firstly, 
150 µL ethylene diamine and 90 mL anhydrous toluene were added into the flask. 1.5g 
ZSM-5@UiO-66 composite particles were then added to the ethylene diamine/toluene 
 24 
 
solution. After the suspension was refluxed at 385 K for 12 h, the ZSM-5@UiO-66 
particles were collected by centrifugation and washed by dispersing in absolute ethanol. 
The ethanol washing and centrifugation steps were repeated three times. Finally, the 
particles were dried in convective oven at 343 K overnight. The as-obtained sample 
was denoted as ED-ZSM-5@UiO-66. 
The intrinsic acid sites in zeolite micropores were deactivated during the 
synthesis and incorporation of amine groups. Several solution exchange methods 
followed by intermediate temperature treatment were tested to optimize the catalytic 
activity. The ED-ZSM-5@UiO-66 was soaked in exchange solution in order to extract 
free ethylene diamine trapped in zeolite micropores. The exchange solutions include 
NH4NO3 water solution, NH4NO3 ethanol solution, and HCl ethanol solution (with 
different concentrations). The general exchange procedure is described as follows. The 
exchange was performed in a 50 mL flask equipped with a reflux condenser and heated 
in a temperature controlled oil bath under atmospheric pressure and magnetic stirring. 
0.1 g ED-ZSM-5@UiO-66 was added to 20 mL exchange solution. The mixture was 
refluxed at 363 K 3 times for a total of 6 h. The exchanged particles were washed with 
water and ethanol repeatedly. The sample was then dried at 423K in vacuum oven. The 
sample was denoted as NH4NO3-ED-ZSM-5@UiO-66 or HCl-ED-ZSM-5@UiO-66 
after this step. 
2.2.5 Product characterizations 
The crystalline phase of the samples was determined by X-Ray powder 
diffraction (XRD) using Bruker D8 Advance Lynx Powder Diffractometer. The 
integration time was 0.3 hours and the step size was 0.032 degrees/second. The 
 25 
 
morphology and elemental analysis of the samples were obtained by a scanning 
electron microscope (SEM, Hitachi SU-70) equipped with an energy dispersive X-ray 
(EDX) spectrometer. Transmission electron microscopy (TEM) images were recorded 
on a JEM 2100 LaB6 microscope at an accelerating voltage of 200 KV. Nitrogen (N2) 
and Argon (Ar) adsorption-desorption measurements were carried out at 77 K and 87 
K on an Autosorb-iQ analyzer (Quantachrome Instruments), respectively. Prior to the 
N2 and Ar measurements, samples were outgassed at 423 K overnight. The FT-IR 
spectrum was recorded with a spectrometer (Nicolet Magna-IR 560) in the range of 
4000 - 400 cm-1.  Each sample was measured with 128 scans at an effective resolution 
of 4 cm-1. The thermogravimetric analysis (TGA) was conducted using a 
thermogravimetric analyzer (TGA 2950, TA Instruments) under a mixed air and N2 
flow (100 mL min-1, 60% air and 40% N2) with a heating rate of 5 K min-1 from 298 K 
to 1073 K. 
2.2.6 Catalytic reaction over ZSM-5@UiO-66 composite 
The liquid phase catalytic conversion of benzylidene malononitrile from 
malononitrile and benzaldehyde dimethyl acetal (Scheme 2-2) was carried out in a 
three-necked flask equipped with a reflux condenser and heated in a temperature 
controlled oil bath under atmospheric pressure and magnetic stirring (0.5” stirring bar 
and 500 rpm stirring speed) conditions. In a typical experiment, 20 mL acetonitrile, 
0.0866 g malononitrile (1.31 mmol), 7.5 μL DI water, and 0.05 g catalyst (NH4NO3-
ED-ZSM-5@UiO-66 or HCl-ED-ZSM-5@UiO-66) were added into the flask in 
sequence. After bubbled the mixture with flowing helium for 0.5 h, the flask was 
immersed in the oil bath preheated at 353 K. The reaction mixture was maintained for 
 26 
 
0.5 h at the required reaction temperature and stirring conditions and then 0.2045 mL 
of benzaldehyde dimethyl acetal (1.36 mmol) was added. This moment of addition was 
taken as the initial reaction time. Liquid samples were withdrawn at regular intervals 
and analyzed by the gas chromatograph (Agilent 7890A) equipped with a methyl-
siloxane capillary column (HP-1, 50.0 m x 320 μm x 0.52 μm) connected to a flame 
ionization detector (FID). The influence of external mass transfer limitations on the 
reaction rates was ruled out by running the reactions at a high enough stirring speed 
(500 rpm), showing a further increase in the stirring speed did not enhance the reaction 
rate. The reactant mixture without addition of zeolite catalysts showed no conversion 
under the investigated reaction conditions.  
The GC calibration curves of all the reactants (benzaldehyde dimethyl acetal, 
malononitrile) and products (benzaldehyde, benzylidene malononitrile) in the cascade 
reactions were obtained by the external calibration method. The maximum 
concentration of the chemicals in the catalytic reaction was 0.068 mol L-1. The standard 
samples were prepared with concentrations of 0.015 mol L-1, 0.030 mol L-1, 0.045 mol 
L-1, 0.060 mol L-1 and 0.075 mol L-1. The calibration curves are shown in Figure 2-1. 
All curves show a linear response of peak area vs. concentration with R2 larger than 
0.9996. 
 27 
 
0.00 0.02 0.04 0.06 0.08
0
500
1000
1500
2000
2500
3000
3500
 
 
P
e
a
k
 
a
r
e
a
 
(
p
A
*
s
)
Concentration (mol L
-1
)
 Benzaldehyde Dimethyl Acetal
Peak area= 36683×c - 11.529
 Benzaldehyde
Peak area= 8334×c - 2.9905
 Benzylidene Malononitrile
Peak area= 28447×c - 18.171
 Malononitrile
Peak area= 41845×c + 22.805
 
Figure 2-1. Calibration curves of benzaldehyde dimethyl acetal, malononitrile, 
benzaldehyde and benzylidene malononitrile. 
 
2.3 Results and Discussion 
The morphologies of ZSM-5, UiO-66, and ZSM-5@UiO-66 composite samples 
were observed with scanning electron microscope (SEM) and transmission electron 
microscope (TEM), and the representative images are shown in Figure 2-2. The ZSM-
5 zeolite (Figure 2-2(A)) consists of short cylindrical particles with well crystallized 
smooth surfaces. The average width the particles is 250 nm and thickness is 180 nm. 
The UiO-66 (Figure 2-2(B)) contains aggregated cubic particle with an average size of 
~ 100 nm. ZSM-5@UiO-66 composite (Figure 2-2(D)-(F)) contains bulk ZSM-5 cores 
and sparse UiO-66 particles on the ZSM-5 surface, showing the formation of core-shell 
zeolite@MOF composite clearly. In particular, Figure 2-2 (E) shows the side view of 
 28 
 
the cylinder shape ZSM-5 and Figure 2-2 (F) shows the top view of the cylinder shape 
ZSM-5. The similarity between the lattice parameters of ZSM-5 (a = 20.090 Å, b = 
19.738 Å, c = 13.142 Å, α = β = γ =90º) and UiO-66 (a = b = c = 20.700 Å, α = β = γ 
=90º) might lead to an epitaxial growth of UiO-66 from ZSM-5 crystal surface[60, 
128]. Nanosized zeolite seeds have been reported to promote fast growth of MOF 
crystals[129]. Extra experiments using ZSM-5 cores with different size and silica-
alumina ratio were investigated and presented at the last of this section. 
 
Figure 2-2. SEM images of (A) ZSM-5 zeolite, (B) UiO-66 MOF, and TEM images of 
(C) ZSM-5,  (D), (E) and (F) ZSM-5@UiO-66. 
 
In order to confirm the composition and crystallinity of the particles, powder 
X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) spectroscopy were 
employed. Figure 2-3 shows the XRD patterns of the synthesized ZSM-5, UiO-66, 
ZSM-5@UiO-66 and ED-ZSM-5@UiO-66 particles, respectively. Both ZSM-5 (a) and 
 29 
 
UiO-66 (b) are highly crystallized, resembling the characteristic of a crystalline ZSM-
5 and UiO-66 reported in literature[60, 125]. The ZSM-5@UiO-66 (c) composite 
consists of diffraction peaks from both UiO-66 and ZSM-5, indicating the presence of 
both phases in the composite materials. In addition, the absence of new diffraction 
peaks or broadening of characteristic peaks of ZSM-5 or UiO-66 indicates no other 
structure formation and deterioration of the crystalline phases in the synthesis 
conditions. In addition, all of the crystalline phases were well preserved after the 
addition of ethylene diamine (ED). 
5 10 15 20 25 30 35 40
(d)
(c)
(a)
I
n
t
e
n
s
i
t
y
 
(
a
.
u
.
)
2(degree)
(b)
 
Figure 2-3. XRD patterns of (a) ZSM-5, (b) UiO-66, (c) ZSM-5@UiO-66, and (d) ED-
ZSM-5@UiO-66. 
 
The elemental compositions of the ZSM-5 solid core and ZSM-5@UiO-66 
core-shell particle were verified with EDX spectroscopy, as shown in Figure 2-4, to 
distinguish the core-shell structure from a physical mixture of ZSM-5 and UiO-66. The 
 30 
 
EDX spectrum (A) is of the ZSM-5 solid core particles. The ZSM-5 construction 
element Si, Al and O are shown in the figure with Kα characteristic X-ray energy of 
1.739 KeV, 1.486 KeV and 0.525 KeV, indicating the presence of zeolite particles. The 
EDX spectrum (B) is of the core-shell particles and is comprised of Si, Al, O and Zr 
peaks, indicating the presence of zeolite and MOF structures. The primary construction 
element of UiO-66 Zr is shown with Lα characteristic X-ray energy of 2.042 KeV. The 
C peaks in both figures are from the carbon tape used for sample preparation in SEM 
characterization. The peaks at 0 come from the X-ray beam of the instrument. The EDX 
was done during the SEM and was performed on isolated particles, thus confirms the 
successful growth of UiO-66 onto ZSM-5 and the preservation of the crystallinity of 
both materials.  
 
 
 
 31 
 
0.0 0.5 1.0 1.5 2.0 2.5
(A)
I
n
t
e
n
s
i
t
y
 
(
a
.
u
.
)
Energy (KeV)
C K
O K
Al K
Si K
 
0.0 0.5 1.0 1.5 2.0 2.5
Zr L
Si K
Al K
O KI
n
t
e
n
s
i
t
y
 
(
a
.
u
.
)
Energy (KeV)
C K
(B)
 
Figure 2-4. EDX spectra of as-synthesized (A) ZSM-5 zeolite and (B) ZSM-5@UiO-
66 core-shell composite. 
 
 32 
 
N2 and Ar adsorption/desorption isotherms were used to characterize the 
textural properties of the samples. In particular, N2 adsorption-desorption isotherms 
(Figure 2-5) were carried out to determine the surface area and total pore volume of the 
samples. The surface area was calculated using the multipoint BET method. The total 
pore volume was calculated using the NLDFT method on the adsorption branch. The 
textural parameters of the synthesized samples extracted from N2 and Ar 
adsorption/desorption measurements are summarized in Table 2-1. The surface area of 
UiO-66 was comparable to the value reported in literature. The ZSM-5 showed a 
slightly surface area than the normal microporous ZSM-5 due to its smaller particle 
size. The surface area and total pore volume of core-shell structure shows a 
combination of ZSM-5 and UiO-66, revealing the accessibility of the micropores of 
both materials. The surface area and total pore volume decreased upon addition of ED 
because ED occupied the micropores of the sample. The surface area and total pore 
volume resumed after the sample was washed with HCl solution.  
 33 
 
0.0 0.2 0.4 0.6 0.8 1.0
0
100
200
300
400
N
2
 
v
o
l
u
m
e
 
a
d
s
o
r
b
e
d
 
(
c
m
3
g
-
1
 
S
T
P
)
P/P
0
 UiO-66
 ZSM-5@UiO-66
 HCl-ED-ZSM-5@UiO-66
 ED-ZSM-5@UiO-66
 ZSM-5
 
Figure 2-5. N2 adsorption-desorption isotherms of UiO-66, ZSM-5, ZSM-5@UiO-66, 
ED-ZSM-5@UiO-66, and HCl-ED-ZSM-5@UiO-66, respectively. 
 
Table 2-1.  Textural properties of UiO-66, ZSM-5, ZSM-5@UiO-66, ED-ZSM-
5@UiO-66, and HCl-ED-ZSM-5@UiO-66, derived from N2 and Ar isotherms. 
Samples 
Smicro
a 
[m
2
 g
-1
] 
Sext
a 
[m
2
 g
-1
] 
Vmicro
a 
[cm
3
 g
-1
] 
Vtotal
b 
[cm
3
 g
-1
] 
SBET
c 
[m
2
 g
-1
] 
UiO-66 1002 47 0.38 0.43 1048 
ZSM-5 390 76 0.15 0.25 466 
ZSM-5@UiO-66 570 51 0.22 0.29 621 
ED-ZSM-5@UiO-66 403 68 0.16 0.25 471 
HCl- ED-ZSM-
5@UiO-66 
466 98 0.19 0.31 564 
Samples 
Smicro
d 
[m
2
 g
-1
] 
Sext
d 
[m
2
 g
-1
] 
Vmicro
d 
[cm
3
 g
-1
] 
Vtotal
e 
[cm
3
 g
-1
] 
SBET
f 
[m
2
 g
-1
] 
UiO-66 837 42 0.30 0.35 879 
ZSM-5 458 28 0.17 0.22 486 
ZSM-5@UiO-66 513 41 0.19 0.25 554 
ED-ZSM-5@UiO-66 410 47 0.15 0.22 456 
HCl-ED-ZSM-
5@UiO-66 
475 60 0.17 0.27 536 
a Determined from t-plot method applied to the N2 isotherm. b Total pore volume calculated at P/P0=0.95 
applied to the N2 isotherm. cDetermined from multi-point BET method applied to the N2 isotherm. d 
Determined from t-plot method applied to the Ar isotherm. e Total pore volume calculated at P/P0=0.95 
applied to the Ar isotherm. fDetermined from multi-point BET method applied to the Ar isotherm.  
 34 
 
Ar adsorption-desorption measurements were conducted to examine the 
porosity features of the composite samples. In Figure 2-6 (A), the Ar isotherms show 
similar behavior with N2 isotherms. The pore size distributions of the materials were 
derived from the Ar adsorption-desorption isotherms using the non-local density 
functional theory (NLDFT) method on the adsorption branches assuming 
spherical/cylindrical pores are shown in Figure 2-6 (B). The pore sizes of UiO-66 are 
7.2 Å and 9.6 Å, respectively, smaller than the ones corresponding to the tetrahedral 
cages (8 Å) and octahedral cages (11 Å). The spherical/cylindrical pore model was also 
used to calculate the pore size of pure ZSM-5, resulting in larger pore size (7.3 Å) than 
its theoretical value of 5.4-5.6 Å. The isotherm of as-synthesized ZSM-5@UiO-66 
shown in Figure 2-6 (B) illustrating the combination of the two pore systems inherited 
from ZSM-5 and UiO-66, suggesting no intergrowth of the two materials. 
NLDFT pore size analysis in Figure 2-6(B) shows that ZSM-5 has a micropore 
size of 7.1 Å, larger than the typical micropore size (5.4-5.6 Å) of ZSM-5. The analysis 
was derived from the adsorption branch of Ar isotherms on the basis of 
spherical/cylindrical pore model. To verify the influences of pore model selected in the 
analysis on the micropore sizes of ZSM-5 and UiO-66 materials, the Ar adsorption 
branches were further analyzed on the basis of a cylindrical pore model, and the 
resultant pore size distributions are shown in Figure 2-6(C). ZSM-5 has a typical pore 
size of ~ 5.2 Å, while UiO-66 has a micropore size of ~ 6.1 Å and ~ 5.0 Å (a shoulder 
next to the peak), corresponding to its tetrahedral cages and octahedral cages, 
respectively. These results also demonstrate that ZSM-5@UiO-66-NH2 and ZSM-
5@UiO-66 are comprised of dual micropore systems. 
 35 
 
0.0 0.2 0.4 0.6 0.8 1.0
0
100
200
300
400
500
 
 
A
r
 
v
o
l
u
m
e
 
a
d
s
o
r
b
e
d
 
(
c
m
3
g
-
1
 
S
T
P
)
P/P
0
 UiO-66
 ZSM5@UiO66
 HCl-ED-ZSM5@UiO66
 ED-ZSM5@UiO66
 ZSM-5
(A)
6 8 10 12 14 16 18 20
0.0
0.1
0.2
0.3
0.4
0.5
 UiO-66
 ZSM5@UiO66
 HCl-ED-ZSM5@UiO66
 ED-ZSM5@UiO66
 ZSM-5
d
V
/
d
l
o
g
D
 
(
c
m
3
g
-
1
 
S
T
P
)
(B)
 
 
Pore width (Å)
7.18Å
9.58Å
4 5 6 7 8 9 1 11 12 13 14 15
0.0
0.1
0.2
0.3
0.4
5
0.6
(C) UiO-66
 ZSM5@UiO66
 HCl-ED-ZSM5@UiO66
 ED SM @UiO66
 ZSM5
d
V
/
d
l
o
g
D
 
(
c
m
3
g
-
1
 
S
T
P
)
5.22Å
6. 2
 
 
Pore width (Å)
 
Figure 2-6. Ar adsorption-desorption isotherms (A), and the corresponding pore size 
distributions (B) derived from Ar sorption (NLDFT on the adsorption branch on the 
basis of spherical/cylindrical pore model) and (C) NLDFT on the adsorption branch on 
the basis of cylindrical pore model, of as-synthesized UiO-66, ZSM-5, ZSM-5@UiO-
66, ED-ZSM-5@UiO-66, and HCl- ED-ZSM-5@UiO-66, respectively. 
 
 36 
 
Infrared spectroscopy was applied to characterize the amine group grafting. The 
absorption bands centered around 1390, 1506, and 1583 cm-1 correspond to the O-C-O 
symmetric stretching (νs,O-C-O), C-C ring symmetric stretch (νs,C-C), and O-C-O 
asymmetric stretching (νas,O-C-O) vibrational modes, respectively, of the organic BDC 
linkers in UiO-66[130]. The absorption band centered at 1087 cm-1 is attributed to the 
asymmetric stretching vibration of T-O-T (T: Si or Al) (νas,T-O-T) in the framework of 
the ZSM-5 zeolite[131]. The appearance of these absorption bands, for example, 1087 
cm-1 and 1390 cm-1, in ZSM-5@UiO-66 and HCl-ED-ZSM-5@UiO-66 suggests the 
coexistence of ZSM-5 and UiO-66 in the composite. The presence of amine groups in 
HCl-ED-ZSM-5@UiO-66 is revealed by the asymmetric (νas,C-H = 3016 cm-1) and 
symmetric (νs,C-H = 2947 cm-1) stretching vibrations of C-H and asymmetric stretching 
(νas,N-H = 3460 cm-1) of  bonded –NH2, respectively[132]. 
1600 1400 1200 1000

as,O-C-O

s,C-C

s,O-C-O
 
 
Wavenumber (cm
-1
)
 ZSM-5
 UiO-66
 ZSM-5@UiO-66
 HCl-ED-ZSM-5@UiO-66

as,T-O-T
3200 2800

as,C-H

s,C-H
(B)
I
n
t
e
n
s
i
t
y
 
(
a
.
u
.
)
 
 

as,N-H
 
Figure 2-7. FTIR spectra of UiO-66, ZSM-5, ZSM-5@UiO-66, ED-ZSM-5@UiO-66, 
and HCl-ED-ZSM-5@UiO-66, respectively. 
 
 37 
 
 Thermogravimetric analysis (TGA) was performed to study the thermal 
stability and the mass fractions of UiO-66 and ZSM-5 in the composite materials. 
Figure 2-8 shows the TGA curves of ZSM-5, UiO-66, ZSM-5@UiO-66 and HCl-ED-
ZSM-5@UiO-66, respectively. The weight loss in the proton-form ZSM-5 is 3.3 wt%, 
due to desorption of moisture adsorbed in the zeolite. UiO-66 shows the weight loss in 
two stages with increasing temperature. The first stage of weight loss happened below 
650 K, which resulted from the moisture desorption from the UiO-66 sample. The 
second stage of weight loss stayed between 690 K and 800 K, which is mainly due to 
the decomposition of organic component in the sample. Clearly, UiO-66 is stable at 
temperature below ~ 650 K in air. The trend of ZSM-5@UiO-66 and HCl-ED-ZSM-
5@UiO-66 are similar to UiO-66 with a total weight loss of 23.5 wt%.  The 
composition of UiO-66 and ZSM-5 in the composite particles therefore can be 
estimated from these TGA curves. The calculation shows that the composite consists 
of 41.4 wt% UiO-66.   
 38 
 
300 400 500 600 700 800 900 1000
40
50
60
70
80
90
100
W
e
i
g
h
t
 
l
o
s
s
 
(
%
)
Temperature (K)
 ZSM-5
 ZSM-5@UiO-66
 HCl-ED-ZSM-5@UiO-66
 UiO-66
 
Figure 2-8. TGA curves of ZSM-5, UiO-66, ZSM-5@UiO-66 and HCl-ED-ZSM-
5@UiO-66, respectively. 
 
 During the synthesis of ZSM-5@UiO-66 composite using ZSM-5 cores with 
different silica-alumina ratio (SAR), it was found that ZSM-5 cores with lower SAR 
tend to promote the growth of MOF on the surface of ZSM-5. Figure 2-9 shows the 
SEM images of ZSM-5@UiO-66 with ZSM-5 SAR of ∞, 100 and 40, and their bare 
ZSM-5 core counterparts, respectively. 
 39 
 
 
Figure 2-9. SEM images of (A) (B) ZSM-5 and ZSM-5@UiO-66 with SAR=∞, (C) 
(D) ZSM-5 and ZSM-5@UiO-66 with SAR=100, (E) (F) ZSM-5 and ZSM-5@UiO-66 
with SAR=40. 
 
Figure 2-9 (A) and (B) show the growth of UiO-66 around ZSM-5 with a SAR 
of ∞. Compared to the original ZSM-5 core in (A), there is no growth of MOF species 
on the surface of the zeolite particles. When the aluminum content in the zeolite 
framework increases, as shown in Figure 2-9 (C) and (D), they form discrete UiO-66 
particles surrounding the zeolite cores. If the aluminum content further increases, a 
 40 
 
complete shell of UiO-66 is formed around the zeolite cores, as shown in Figure 2-9 
(E) and (F). This UiO-66 growth trend shows that the affinity of UiO-66 to ZSM-5 
increases with the increase of aluminum content in the ZSM-5 framework. This should 
be caused by the increasing hydrophilicity of the zeolite framework with more Al 
inside. These results suggest the direction for making zeolite@MOF composite in two 
guidelines: the lattice parameters of the two materials should be similar and the affinity 
between zeolite and MOF should be enhanced. 
The catalytic activity of the composite porous materials was studied in a two-
step tandem reaction process that requires both acid and basic sites. The cascade 
reaction studied involved an acetal hydrolysis followed by a Knoevenagel 
condensation. More specifically, benzaldehyde dimethyl acetal was hydrolyzed to 
produce benzaldehyde which reacts with malononitrile to give benzylidene 
malononitrile (see Scheme 2-2). The first reaction step requires acid sites which are 
supplied by the ZSM-5 core, while the condensation step involves the basic sites which 
are provided by the amine groups in the MOF shell.  
 
Scheme 2-2. One-pot acetal hydrolysis-Knoevenagel condensation cascade reaction. 
 
Several activation procedures were adopted to resume the acid catalytic activity 
of the composite. The conventional activation method for pure zeolite using ammonium 
 41 
 
nitrate water solution was initially tried. The ammonium nitrate in ethanol was also 
used as the exchange medium. HCl in ethanol solution is adopted as a stronger 
exchange medium. The reaction results as well as control experiments of pure ZSM-5 
and UiO-66 are listed in Table 2-2 and will be discussed in detail later. The yield is 
calculated by dividing the amount of the obtained product by the theoretical yield. The 
reaction rate is calculated assuming a first-order reaction for benzaldehyde dimethyl 
acetal.   
 42 
 
Table 2-2. Catalytic Reaction Results Summary 
a The sample is in as-synthesized form if no exchange solution is mentioned. b The results were calculated based on GC data after 24h of reaction 
Catalyst 
Exchange 
Solutiona 
Evacuate 
Temperature 
(K) 
Weight of 
Catalyst 
(mg) 
Conversion of 
Benzaldehyde 
Dimethyl 
Acetal (%)b 
Yield of 
Benzaldehyde 
(%)b 
Yield of 
Benzylidene 
Malononitrile 
(%)b 
Rate 
Constant 
(h-1 gcat-1) 
ED-UiO-66 HCl/Ethanol 423 50.1 9.5 4.2 5.2 0.08 
ZSM-5  423 52.0 87.8 81.7 6.1 7.47 
ED-ZSM-5  423 50.0 0 0 0 0 
ED-ZSM-5 HCl/Ethanol 423 51.0 74 74 0 6.59 
ZSM-5@UiO-66  423 49.9 82.8 78.3 4.5 3.97 
ED-ZSM-5@UiO-66  423 52.7 0 0 0 0 
ED-ZSM-5@UiO-66 NH4NO3/H2O 343 29.3 16.5 2.5 14 0.28 
ED-ZSM-5@UiO-66 NH4NO3/Ethanol 343 44.7 0 0 0 0 
ED-ZSM-5@UiO-66 HCl/Ethanol 343 31.7 11.2 0.8 10.4 1.47 
ED-ZSM-5@UiO-66 HCl/Ethanol 423 49.7 23 1.5 21.5 1.25 
ED-ZSM-5@UiO-66 HCl/Ethanol 473 50.7 28 21 7 1.01 
ED-ZSM-5@UiO-66 HCl/Ethanol 423 201.0 89.6 14.8 74.8 0.74 
 43 
 
 The as-synthesized core-shell composite were dried at 423 K and tested in the 
catalytic reaction. The molar fraction of each component versus reaction time is shown 
in Figure 2-10. The reaction result showed that only the first reaction took place. The 
trace amount of final product benzylidene malononitrile may come from the 
equilibrium conversion of benzaldehyde.  
0 5 10 15 20 25
0
20
40
60
80
100
 
 
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-10. Catalytic reaction results of as-synthesized ZSM-5@UiO-66 composite 
evacuated at 423 K. Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde and 
benzylidene malononitrile versus reaction time. 
 
The composite material after incorporation of amine groups (ED-ZSM-
5@UiO-66) was dried at the same temperature (423 K) and tested in the catalytic 
reaction. No first or second step product was detected in the reaction period of 24h. 
This result is consistent with the assumption that ethylene diamine blocked the acid 
sites in ZSM-5 micropores. 
 44 
 
 NH4NO3 ethanol solution and NH4NO3 water solution was adopted as the 
exchange solution for ED-ZSM-5@UiO-66. Both of the exchanged samples were dried 
in vacuum oven at 343 K overnight before reaction. The sample exchanged with 1 M 
NH4NO3 water solution showed activity for both products. The molar fraction of each 
component vs time is plotted in Figure 2-11.The conversion of benzaldehyde dimethyl 
acetal reached 16.5 % after 24 hours of reaction, while the selectivity of benzylidene 
malononitrile was 84.8 %. The rate constant was relatively low and the reaction did not 
reach equilibrium after 24h of reaction. The sample exchanged with NH4NO3 ethanol 
solution showed no activity because NH4NO3 has very low solubility in ethanol. Higher 
concentration of NH4NO3 can be obtained in DMF. However, neither of the organic 
NH4NO3 solutions can activate the composite. 
0 5 10 15 20
0
20
40
60
80
100
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
 
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-11. Catalytic reaction results of ED-ZSM-5@UiO-66 composite treated with 
1 mol L-1 NH4NO3 water solution, evacuated at 343 K. Molar fraction of benzaldehyde 
dimethyl acetal, benzaldehyde and benzylidene malononitrile versus reaction time. 
 
 45 
 
HCl ethanol solution was then adopted as the exchange medium. The 
equilibrium concentration of benzaldehyde dimethyl acetal using HCl treated sample 
as catalyst is relatively low compared to that using NH4NO3 water solution treated 
sample as catalyst, however, the higher reaction rate makes this activation method more 
promising. 
A series of experiments with different evacuation temperature (343 K, 423 K, 
and 473 K) is carried out to optimize the equilibrium concentration of benzylidene 
malononitrile. The molar fraction of each component versus reaction time is shown in 
Figure 2-12. Figure 2-12 (A) shows the reaction result of the composite at an evacuation 
temperature of 343 K. The reaction reached equilibrium after 6 hours of reaction. The 
increase in evacuation temperature to 423 K enhanced the activity as well as the 
stability of the catalyst. The equilibrium concentration for benzylidene malononitrile 
was almost two fold of the 343 K treated sample. However, when the evacuation 
temperature was further raised to 473 K, the reaction showed a quite different trend. 
The benzaldehyde dimethyl acetal conversion increased while the selectivity for the 
final products dropped dramatically: the intermediate product has a higher selectivity 
over the final product, which is not preferable. This could be caused by the 
decomposition of ethylene diamine at high temperature, leading to the loss of basic 
catalytic activity. 
 46 
 
0 5 10 15 20 25
0
20
40
60
80
100
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
(A)
 
0 5 10 15 20 25
0
20
40
60
80
100
(B)
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
0 5 10 15 20 25
0
20
40
60
80
100
(C)
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-12. Catalytic reaction results of ED-ZSM-5@UiO-66 composite treated with 
HCl ethanol solution, evacuated at (A) 343 K, (B) 423 K, (C) 473 K.  
 
 47 
 
The conversion of benzaldehyde dimethyl acetal, yield of benzaldehyde, yield 
and selectivity of benzylidene malononitrile and rate constant of the three reactions are 
compared in Figure 2-13. The conversion of benzaldehyde dimethyl acetal increased 
with the evacuation temperature, which is caused by the thermal activation of ZSM-5. 
The similarity of reaction trends between 343 K and 423 K treated samples suggests 
that the reaction in this temperature range was controlled by the first step reaction. 
The reaction rate constant of each catalysts is calculated using the following 
equation assuming a first-order reaction, 
𝑘𝑡 = 𝑙𝑛
1
1 − 𝑥
 
where x is the conversion of benzaldehyde dimethyl acetal, k is the apparent rate 
constant normalized to catalyst mass, t is the reaction time. 
 
 
 
 48 
 
0
5
10
15
20
25
30
35
0
5
10
15
20
25
30
35
473 K423 K
  
Evacuation Temperature (K)
 Conversion of Benzaldehyde Dimethyl Acetal
 Yield of Benzaldehyde
 Yield of Benzylidene Malononitrile
343 K
(A)
 
0
20
40
60
80
10
 
S
e
l
e
c
t
i
v
i
t
y
 
o
f
 
B
e
n
z
y
l
i
d
e
n
e
 
M
a
l
o
n
o
n
i
t
r
i
l
e
 
(
%
)
Evacuation Temperature (K)
 Sel ctivity of Benzylidene Malononitrile
 Rate C nsta t
343 K 423 K 473 
0.0
0.4
0.8
1.2
1.6
2.0
(B)
R
a
t
e
 
C
o
n
s
t
a
n
t
 
(
h
-
1
 
g
c
a
t
-
1
)
 
Figure 2-13. A comparison of benzaldehyde dimethyl acetal conversion, benzaldehyde 
yield, benzylidene malononitrile yield and selectivity, rate constant of the composite 
treated with HCl ethanol solution and evacuated at 343 K, 423 K and 473 K. 
 
 49 
 
The sample treated with HCl ethanol solution and evacuated at 423 K showed 
the best catalytic performance and therefore, was tested again in the catalytic reaction 
using a larger amount. The results (Figure 2-14 (A)) showed that the tandem reaction 
was again successfully performed, with the yield of benzylidene malononitrile reached 
80% and selectivity reached 88.9 %. The amount of catalyst used in this test was four 
times higher than the original trial (see Table 2-2). The conversion of benzaldehyde 
dimethyl acetal also showed four-fold increase. The selectivity of the final product was 
slightly lower and the rate constant remained the same. 
0 5 10 15 20 25
0
20
40
60
80
100
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
 
 
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-14 (A). Catalytic reaction results of HCl-ED-ZSM-5@UiO-66 composite. 
Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde and benzylidene 
malononitrile versus reaction time. 
 
 The kinetics of this cascade reaction over scaled up HCl-ED-ZSM-5@UiO-66 
composite is studied assuming a first-order cascade reaction model:  
𝐴
       𝑘1       
→      𝑄
        𝑘2       
→      𝑆 
 50 
 
𝑟𝐴 = 𝑘1𝐶𝐴 
𝑟𝑄 = 𝑘1𝐶𝐴 − 𝑘2𝐶𝑄 
𝑟𝑠 = 𝑘2𝐶𝑄 
Here A stands for benzaldehyde dimethyl acetal, Q stands for benzaldehyde and S 
stands for benzylidene malononitrile respectively. Integration gives: 
𝐶𝐴 = 𝐶𝐴0𝑒
−𝑘1𝑡 
𝐶𝑄 =
𝑘1𝐶𝐴0
𝑘2 − 𝑘1
 (𝑒−𝑘1𝑡 − 𝑒−𝑘2𝑡) 
𝐶𝑠 = 𝐶𝐴0 − 𝐶𝐴 − 𝐶𝑄 
The experimental data (solid line) in Figure 2-14 (A) and the simulated reaction 
trend (dash line) are compared in Figure 2-14 (B). The reaction rate constants for first 
and second step are 0.74 h-1 gcat-1 and 1.05 h-1 gcat-1, respectively. 
0 5 10 15 20 25
0
20
40
60
80
100
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-14 (B). Comparison of experiment and simulation results of catalytic reaction 
results of HCl-ED-ZSM-5@UiO-66 composite. 
 
 51 
 
 
0 5 10 15 20 25
0
20
40
60
80
100
(A)
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
0 5 10 15 20 25
0
20
40
60
80
100
(B)
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene alononitrile
 
0 5 10 15 20 25
0
20
40
6
8
100
(C)
 
 
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 2-15. Catalytic reaction results of (A) ZSM-5, (B) ED-ZSM-5, (C) HCl-ED-
ZSM-5. Molar fraction of benzaldehyde dimethyl acetal, benzaldehyde and 
benzylidene malononitrile versus reaction time. 
 
 52 
 
The control catalytic reaction experiments were carried out on both of the raw 
materials. As-synthesized ZSM-5, ED-ZSM-5 and HCl-ED-ZSM-5 were tested in the 
catalytic reaction. The reaction results are shown in Figure 2-15 with the molar fraction 
of each component versus reaction time. 
As shown in Figure 2-15 (A), the pure ZSM-5 showed a good catalytic activity 
for the first step reaction. Figure 2-15 (B) shows the reaction result of ZSM-5 after 
soaking in ethylene diamine solution as the catalyst. There was no trace for the first 
step reaction because the active sites in ZSM-5 were all blocked by ethylene diamine 
and could not be removed by simply heating up to 423 K. The catalytic activity resumed 
after the sample was treated with HCl ethanol solution. This set of control experiment 
on ZSM-5 was consistent with the N2 and Ar adsorption-desorption results that the 
ethylene diamine occupied the micropores of ZSM-5 and was washed out by HCl 
ethanol solution. 
The rate constants of the reactions catalyzed by ZSM-5 are 7.47 h-1 gcat-1 for 
ZSM-5 and 6.59 h-1 gcat-1 for HCl-ED-ZSM-5. The rate constant decreased to 3.97 h-1 
gcat-1 in the as-synthesized ZSM-5@UiO-66 as a result of diffusion resistance of the 
UiO-66 shell. 
The control experiment on UiO-66 was carried out using HCl-ED-UiO-66 
(UiO-66 soaked in ethylene diamine solution and exchanged in HCL ethanol solution). 
The basic catalytic activity of UiO-66 has been confirmed by testing pure ZSM-5 
(Figure 2-15 (A) and (C)). The reaction result of HCl-ED-UiO-66 is shown in Figure 
2-16. There was an almost negligible conversion of benzaldehyde dimethyl acetal to 
 53 
 
benzaldehyde and benzylidene malononitrile. This result showed that UiO-66 does not 
contribute to the first step reaction. 
0 5 10 15 20 25
0
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 Benzaldehyde dimethyl acetal
 Benzaldehyde
 Benzylidene malononitrile
 
Figure 2-16. Catalytic reaction results of HCl-ED-UiO-66. Molar fraction of 
benzaldehyde dimethyl acetal, benzaldehyde and benzylidene malononitrile versus 
reaction time. 
 
The result of control experiments on ZSM-5 and UiO-66 confirms that the 
hydrolysis of the acetal is catalyzed by the Brønsted acid sites in ZSM-5 and the 
Knoevenagel condensation reaction is catalyzed by the basic sites in UiO-66. 
2.4 Conclusions 
In conclusion, ZSM-5@UiO-66 core-shell composite particles were 
synthesized by solvothermal growth of UiO-66 shell on the surface of ZSM-5 particles 
that were pre-synthesized via hydrothermal crystallization. The morphologies of ZSM-
5, UiO-66, and ZSM-5@UiO-66 composite were observed by SEM and TEM, which 
show the formation of core-shell zeolite@MOF composite. The crystallinity of the 
 54 
 
samples was confirmed by XRD and the composition was confirmed by EDX. Textural 
properties of the samples were extracted from N2 and Ar adsorption-desorption 
isotherms, which show the pore systems in the combined nanoporous materials. The 
content of the UiO-66 shell in the composite was calculated by N2 adsorption-
desorption isotherms and TGA data. 
Post-synthetic modification with ethylene diamine in the UiO-66 framework 
incorporated amine groups into the composite. The acidity in ZSM-5 generated by 
aluminum in the tetrahedral site of the zeolite framework and basicity in UiO-66 
originated from the amine groups enabled ZSM-5@UiO-66 composite acid-base 
bifunctionality for catalytic cascade reactions. The synthesis of benzylidene 
malononitrile from malononitrile and benzaldehyde dimethyl acetal, a process 
involving the hydrolysis of the acetal catalyzed by the Brønsted acid sites in zeolite 
followed by a Knoevenagel condensation reaction catalyzed by the basic sites in MOF 
confirmed the bifunctional activity of the ZSM-5@UiO-66 composite. The 
bifunctionality was supported by FTIR and textural properties as complementary 
evidences. 
 
 
 55 
 
Chapter 3: Synthesis and Presynthetic Modification of ZSM-
5@UiO-66 Core-Shell Particles as Bifunctional Catalysts 
3.1 Introduction 
 The functionalization of ZSM-5@UiO-66 into acid-base catalysts was 
successfully achieved by postsynthetic modification of metal sites using ED in Chapter 
2. The synthetic procedure, however, involves multiple complicated steps, especially 
the incorporation of ED onto metal sites while avoiding the deactivation of acid sites 
in zeolite. In this chapter, we aimed to develop a simple alternative approach to 
introduce –NH2 group into the composite catalysts. Synthesis of functional MOFs with 
organic ligands comprised of functional groups has been investigated in literature.[79] 
In this chapter, presynthetic modification was applied to UiO-66 in order to simplify 
the experimental and activation procedures. 
Particularly, the original linker benzene-1,4-dicarboxylic acid (BDC) for UiO-
66 was replaced by 2-aminobenzene-1,4-dicarboxylic acid (NH2-BDC) in the synthesis 
solution. The core-shell composite ZSM-5@UiO-66-NH2 was synthesized using a 
similar procedure as that of ZSM-5@UiO-66 reported in Chapter 1. This synthesis 
yielded UiO-66-NH2 with amine groups on the organic linkers in the MOF framework 
without any post-synthetic modifications. The as-synthesized composite was tested in 
the cascade catalytic reactions of benzaldehyde dimethyl acetal and malononitrile to 
benzylidene malononitrile, whose reaction scheme has been discussed in Chapter 2. 
 56 
 
3.2 Experimental Part 
3.2.1 Materials 
 Tetrapropylammonium hydroxide (TPAOH, 40% in aqueous solution), 
tetraethylorthosilicate (TEOS, 98%), aluminum isopropoxide (99.99%) and ZrCl4 
(99.9%) were purchased from Alfa Aesar. NaOH (97%), malononitrile (99%) and 2-
aminebenzene-1,4-dicarboxylic acid (NH2-BDC, 99%) were purchased from Sigma-
Aldrich. Dimethylformamide (DMF, 99.8%) was purchased from BDH. Hydrochloric 
acid (36.5%-38.0%) was purchased from JT Baker. Acetonitrile (99.9%) was 
purchased from Fisher. Benzaldehyde dimethyl acetal (98%) was purchased from 
SAFC. All chemicals were used as received without further treatment. Deionized (DI) 
water was used in all purpose. The zeolite core particles was synthesized as reported in 
section 2.2.2 in Chapter 2 of this thesis. 
3.2.2 Synthesis of UiO-66-NH2 and ZSM-5@UiO-66-NH2 
A typical procedure for synthesis of ZSM-5@UiO-66-NH2 is shown as follows: 
0.04 g ZrCl4, and 0.031 g NH2-BDC were dissolved in 18.96 g DMF. 0.0125 mL DI 
water was then added to the mixture. The solution was transferred to a Teflon-lined 
steel autoclave and allowed to react at 393 K for 24 h. The product was collected by 
centrifugation and followed by a two-step washing procedure in order to remove the 
unreacted residues encapsulated in the micropores of the material. The first step 
involved stirring exchange with DMF for 3 times. In the second step, the high boiling 
point solvent DMF was exchanged with methanol for 2 times. After washing, the 
sample was dried at 343 K. The synthesis of ZSM-5@UiO-66-NH2 core-shell 
 57 
 
structured composite was carried out using the same procedure as that of UiO-66-NH2 
particles except that 0.284 g ZSM-5 particles was added to the synthesis solution and 
stirred for 1 h to get a stable colloid in the beginning of the synthesis. 
3.2.3 Activation of the catalyst 
 The as-synthesized ZSM-5@UiO-66-NH2 composite was tested in the catalytic 
reaction without any treatment. Meanwhile, the composite was acid-exchanged and 
tested in the catalytic reaction for comparison. The acid exchange was performed in a 
50mL flask equipped with a reflux condenser and heated in a temperature controlled 
oil bath under atmospheric pressure and magnetic stirring. 0.1 g ZSM-5@UiO-66-NH2 
was added to 20 mL 0.1 mol L-1 HCl ethanol solution. The mixture was refluxed at 363 
K 3 times for a total of 6 h. The acid exchanged sample was washed with water and 
ethanol repeatedly and then dried at 473K in vacuum oven. The sample was denoted as 
HCl-ZSM-5@UiO-66-NH2 after this step. 
3.2.4 Product characterizations 
The crystalline phase of catalyst samples was determined by X-Ray powder 
diffraction (XRD) using Bruker D8 Advance Lynx Powder Diffractometer. The 
integration time was 0.3 hours and the step size was 0.032 degrees/second. The 
morphology and elemental analysis of the samples were obtained by a scanning 
electron microscope (SEM, Hitachi SU-70) equipped with an energy dispersive X-ray 
(EDX) spectrometer. Transmission electron microscope (TEM) images were recorded 
on a JEM 2100 LaB6 microscope at an accelerating voltage of 200KV. N2 adsorption-
desorption measurements were carried out at 77 K and on an Autosorb-iQ analyzer 
 58 
 
(Quantachrome Instruments), respectively. Prior to the N2 and Ar measurements, 
samples were outgas at 423 K overnight. The FT-IR spectrum was recorded with a 
spectrometer (Nicolet Magna-IR 560) in the range of 4000 - 400 cm-1.  Each sample 
was measured with 128 scans at an effective resolution of 4 cm-1. 
3.2.5 Catalytic reaction test over ZSM-5@UiO-66-NH2 composite 
The liquid phase catalytic conversion of benzylidene malononitrile from 
malononitrile and benzaldehyde dimethyl acetal (Scheme 2-2) was performed in a 
three-necked flask equipped with a reflux condenser and heated in a temperature 
controlled oil bath under atmospheric pressure and magnetic stirring (0.5” stirring bar 
and 500 rpm stirring speed) conditions. In a typical experiment, 20 mL acetonitrile, 
0.0866 g malononitrile, 7.5 μL DI water, and 0.05 g catalyst were added into the flask 
in sequence. After bubbled the mixture with flowing helium for 0.5 h, the flask was 
immersed in the oil bath preheated at 353 K. The reaction mixture was maintained for 
0.5 h at the required reaction temperature and stirring conditions and then 0.2045 mL 
of benzaldehyde dimethyl acetal (1.36 mmol) was added. This moment of the addition 
was taken as the initial reaction time. Liquid samples were withdrawn at regular 
intervals and analyzed by the gas chromatograph (Agilent 7890A) equipped with a 
methyl-siloxane capillary column (HP-1, 50.0 m x 320 μm x 0.52 μm) connected to a 
flame ionization detector (FID). 
3.3 Results and Discussion 
The morphologies of ZSM-5, UiO-66-NH2, and ZSM-5@UiO-66-NH2 
composite samples were observed with SEM and TEM, and the representative images 
 59 
 
are shown in Figure 3-1. The ZSM-5 zeolite (Figure 3-1 (A)) consists of short 
cylindrical particles with an average width of 250 nm and thickness of 180 nm and well 
crystallized smooth surfaces. The UiO-66-NH2 (Figure 3-1 (B) and (C)) consists of 
hexagonal polyhedrons with an average size of 350 nm. ZSM-5@UiO-66-NH2 
composite (Figure 3-1 (D)-(F)) contains bulk ZSM-5 cores and sparse UiO-66-NH2 
particles on the ZSM-5 surface, showing the formation of core-shell zeolite@MOF 
composite clearly. 
 
Figure 3-1. SEM images of (A) ZSM-5 zeolite, (B) (C) UiO-66 MOF, and (D) ZSM-
5@UiO-66-NH2. TEM images of (E) (F) ZSM-5@UiO-66-NH2. 
 
Powder X-ray diffraction (XRD) and energy-dispersive X-ray (EDX) 
spectroscopy were employed to confirm the composition and crystallinity of the 
particles. Figure 3-2 shows the XRD patterns of ZSM-5, UiO-66-NH2 and ZSM-
5@UiO-66-NH2 particles, respectively. Both ZSM-5 and UiO-66-NH2 are highly 
 60 
 
crystallized. UiO-66-NH2 shows the same diffraction peaks as UiO-66, suggesting that 
they have isoreticular structures. The ZSM-5@UiO-66-NH2 composite consists of 
diffraction peaks from both UiO-66-NH2 and ZSM-5, suggesting the presence of both 
phases in the composite material. In addition, the absence of new diffraction peaks or 
broadening of characteristic peaks of ZSM-5 or UiO-66-NH2 indicates no other 
structure forms and deterioration of the crystalline phases in the synthesis conditions. 
5 10 15 20 25 30 35 40
(c)
(b)
(a)
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2(degree)
 
Figure 3-2. XRD patterns of (a) ZSM-5, (b) UiO-66-NH2 and (c) ZSM-5@UiO-66-
NH2, respectively. 
 
The elemental compositions of the ZSM-5 solid core and ZSM-5@UiO-66-NH2 
composite were verified with EDX spectroscopy (Figure 3-3), to distinguish the core-
shell structure from a physical mixture of ZSM-5 and UiO-66-NH2. Si, Al and O can 
be observed in the EDX spectrum of the ZSM-5 solid core particle with Kα 
 61 
 
characteristic X-ray energy of 1.739 KeV, 1.486 KeV and 0.525 KeV, respectively. 
The EDX spectrum (B) of the core-shell particles is comprised of Si, Al, O, N and Zr 
peaks, showing the presence of zeolite and MOF building elements. The primary 
construction element Zr of UiO-66-NH2 is shown with Lα characteristic X-ray energy 
of 2.042 KeV. The small peak between the C and O peaks could be attributed to N Kα 
characteristic X-ray energy of 0.392 KeV. The C peaks in both figures are from the 
carbon tape used for sample preparation in the SEM characterization. The EDX was 
done during the SEM test and was performed on isolated particles, thus confirming the 
successful growth of UiO-66-NH2 onto ZSM-5. 
 62 
 
0.0 0.5 1.0 1.5 2.0 2.5
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Energy (KeV)
C K
O K
Al K
Si K
(A)
0.0 0.5 1.0 1.5 2.0 2.5
(B)
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Energy (KeV)
N K
Zr L
Si K
l 
O K
C K
 
Figure 3-3. EDX spectra of as-synthesized (A) ZSM-5 zeolite and (B) ZSM-5@UiO-
66-NH2 core-shell composite. 
 63 
 
N2 adsorption-desorption isotherms were used to characterize the textural 
properties (surface area and total pore volume) of the samples as summarized Figure 
3-4. The surface areas of UiO-66-NH2, ZSM-5 and ZSM-5@UiO-66-NH2 calculated 
by the multipoint BET method were 967 m2/g, 466 m2/g and 474 m2/g, respectively. 
The total pore volume of aforementioned samples calculated at P/P0=0.95 were 0.44 
mL/g, 0.25 mL/g and 0.28mL/g, respectively. The surface area and pore volume of 
UiO-66-NH2 were smaller than that of UiO-66 because the amine groups on the linkers 
occupy a portion of the micropore volume. Moreover, these results show that the 
surface area and total pore volume of the core-shell composite are combinations of 
ZSM-5 and UiO-66, revealing the accessibility of the micropores of both materials.  
0.0 0.2 0.4 0.6 0.8 1.0
0
50
100
150
200
250
300
350
400
450
P/P
0
N
2
 
v
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S
T
P
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 UiO-66-NH
2
 ZSM-5@UiO-66-NH
2
 ZSM5
 
Figure 3-4. N2 adsorption-desorption isotherms of UiO-66-NH2, ZSM-5, and ZSM-
5@UiO-66-NH2, respectively. 
 
 64 
 
Infrared spectroscopy was applied to characterize amine groups in the MOF 
framework. The adsorption bands centered around 3390 and 3490 cm-1 showed in 
Figure 3-5 correspond to the primary amine N-H stretching (νs, N-H) vibrational modes 
in the organic linkers in UiO-66. The weak absorption band centered at 1573 cm-1 
stands for the N-H bending (νb, N-H) vibration mode and the absorption bands centered 
around 1160 cm-1 could attribute to the C-N stretching (νs, C-N) vibration mode. The 
appearance of absorption bands at 1082 cm-1 and 1380 cm-1 in ZSM-5@UiO-66-NH2 
suggests the co-existence of ZSM-5 and UiO-66 in the composite, consistent with the 
XRD analysis. 
3000 2500 2000 1500 1000 500
 
 
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Wavenumbers (cm
-1
)
 UiO-66-NH
2
 ZSM-5@UiO-66-NH
2
 ZSM-5
3600 3400 3200

s, N-H
 
Wavenumbers (cm
-1
)
1600 1580 1560

b,N-H
 
Wavenumbers (cm
-1
)
1200 1150 1100 1050

s, C-N
 
Wavenumbers (cm
-1
)
 
Figure 3-5. FTIR spectra of UiO-66-NH2, ZSM-5 and ZSM-5@UiO-66-NH2, 
respectively. 
 
 65 
 
 The surface area calculation implies that the UiO-66-NH2 content in the ZSM-
5@UiO-66-NH2 composite was very low. This result can also be obtained by 
comparing the relative intensity of XRD and FT-IR peaks in the composite that belong 
to UiO-66-NH2 and ZSM-5. This will lead to unequivalent acid and basic site numbers 
in the composite and affect the catalytic performance. 
The catalytic activity of the bifunctional ZSM-5@UiO-66-NH2 composite was 
studied in the reaction shown in Scheme 2-2. The first reaction step requires acid sites 
which can be supplied by the ZSM-5 core, while the second step involves basic sites 
coming from the amine groups on the organic linkers of the UiO-66-NH2. The reaction 
results of as-synthesized ZSM-5@UiO-66-NH2 and acid-exchanged ZSM-5@UiO-66-
NH2 are shown in Figure 3-6 in terms of molar fractions of each component versus 
reaction time. For as-synthesized ZSM-5@UiO-66-NH2 composite, the yield for 
benzylidene malononitrile was 20% after 24 h of reaction, which is comparable to the 
reaction result of HCl-ED-ZSM-5@UiO-66 described in 2.3.  
Figure 3-6 (B) shows catalytic reaction result of the acid-exchanged ZSM-
5@UiO-66-NH2. After acid exchange, the acid activity of ZSM-5 core was resumed to 
the level of pure ZSM-5. This dramatic improvement in acid activity that was not 
presented in the ZSM-5@UiO-66 case (in Chapter 2) indicates that the ethylene 
diamine impairs the acid activity in ZSM-5 greatly and irreversibly. The presynthetic 
modification in the synthesis of ZSM-5@UiO-66-NH2 circumvent the amine grafting 
after synthesis and can preserve the acidity in ZSM-5. 
 66 
 
0 5 10 15 20 25
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20
40
60
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100
(A)
 
 
M
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 Benzaldehyde dimethyl acetal
 Benzaldehyde
 Benzylidene malononitrile
M
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Time (h)
 Benzaldehyde dimethyl acetal
 Benzaldehyde
 Be zylidene malononitrile
(B)
 
Figure 3-6. Catalytic reaction results of as-synthesized ZSM-5@UiO-66-NH2 and 
acid-exchanged ZSM-5@UiO-66-NH2. Molar fraction of benzaldehyde dimethyl 
acetal, benzaldehyde and benzylidene malononitrile versus reaction time. 
 
 
 67 
 
3.4 Conclusions 
The ZSM-5@UiO-66-NH2 core-shell composite was successfully synthesized 
by solvothermal growth of UiO-66-NH2 shell on the surface of ZSM-5 particles that 
were pre-synthesized via hydrothermal crystallization. The morphologies of ZSM-5, 
UiO-66, and ZSM-5@UiO-66-NH2 composite were observed by SEM and TEM, 
clearly showing the formation of core-shell zeolite@MOF composite. The crystallinity 
of the samples was confirmed by XRD and the element composition was confirmed by 
EDX. Textural properties of the samples were extracted from N2 adsorption-desorption 
isotherms, clearly showing the pore systems in the combined nanoporous materials. 
The existence of amine group in the UiO-66-NH2 framework and the composite was 
confirmed by EDX and FT-IR measurements.  
The presynthetic modification of BDC linkers with amine groups endows the 
composite with basic catalytic activity. The as-synthesized composite and acid 
exchanged composite were tested in cascade catalytic reactions. The as-synthesized 
composite showed catalytic activity for both steps of the cascade reaction. The acid-
exchanged composite showed improved performance for the first-step reaction, 
however, the basic activity wasn’t comparable to the acid activity. This is because of 
the low UiO-66-NH2 content in the core-shell composite, derived from the surface area 
calculations and peak intensity comparison in XRD and FT-IR measurements. The 
bifunctionality can be optimized by increasing MOF content in the core-shell 
composite. 
 
 
  
 68 
 
Chapter 4: Synthesis of ZSM-5@MIL-101 Core-Shell Particles 
as Bifunctional Catalysts 
4.1 Introduction 
The synthesis method of ZSM-5@UiO-66 described in Chapter 2 can be readily 
applied to other zeolite@MOF composites. In this chapter the method was expanded 
to MIL-101, another thermally stable MOF capable of postsynthetic modification with 
ethylene diamine in the metal cluster.[58, 100] Commercial ZSM-5 (Figure 4-1 (A)) 
was used as the core. The synthesis solution of MIL-101 contains hydrofluoric acid or 
tetramethylammonium hydroxide (TMAOH) as structure directing agent.[58, 133] 
Either of the substrates will impair the ZSM-5 particles present in the synthesis 
solution. Hydrofluoric acid can dissolve ZSM-5 at room temperature. TMAOH is used 
as structure directing agent in the ZSM-5 synthesis, which could possibly cause etching 
or recrystallization of ZSM-5 particles. 
4.2 Experimental 
4.2.1 Materials 
 Tetramethylammonium hydroxide (TMAOH, 25 wt% water solution), 
Cr(NO3)3·9H2O (98.5%) and benzenedicarboxylate (BDC, 98%) were purchased from 
Alfa Aesar. Malononitrile (99%) and ethylene diamine (ED, 99.5%) were purchased 
from Sigma-Aldrich. Anhydrous toluene (99.5%) was purchased from BDH. 
Hydrochloric acid (36.5%-38.0%) was purchased from JT Baker. Acetonitrile (99.9%) 
was purchased from Fisher. Benzaldehyde dimethyl acetal (98%) was purchased from 
 69 
 
SAFC. All chemicals were used as received without further treatment. Deionized (DI) 
water was used in all purpose. 
4.2.2 Synthesis of MIL-101 and ZSM-5@MIL-101 
There are generally two synthetic systems for MIL-101. One is using acidic 
solution, mainly hydrofluoric acid. The other one contains TMAOH in the solution, 
which is considered milder and adopted here. 0.1823 g TMAOH was dissolved in 
14.8177 g DI water. Then 0.1108 g BDC and 0.2668 g Cr(NO3)3·9H2O were added into 
the mixture. The solution was transferred to a Teflon-lined steel autoclave and allowed 
to react at 453 K for 48 h. The product was collected by centrifugation and washed with 
DI water and ethanol for 3 times each. After washing, the sample was dried in a 
dynamic vacuum oven at 343 K. 
The synthesis of ZSM-5@MIL-101 core-shell structured composite was 
conducted using the same procedure as that of MIL-101 particles except that 0.15 g 
commercial ZSM-5 particles were added to the synthesis solution and stirred for 1 h to 
get a stable colloid in the beginning of the synthesis. 
4.2.3 Incorporation of amine (−NH2) groups into ZSM-5@MIL-101 
composite 
The incorporation of amine groups in the composite was performed in a 150 
mL flask equipped with a reflux condenser and heated in a temperature controlled oil 
bath under atmospheric pressure and magnetic stirring (1” stirring bar and 500 rpm 
stirring speed) conditions. 150 µL ethylene diamine was added to 90 mL anhydrous 
toluene in the flask. 1.5g ZSM-5@MIL-101 particles were added to the solution 
 70 
 
sequentially. The mixture was refluxed at 385 K for 12 h. The particles were collected 
by centrifugation and washed with ethanol for 3 times. The particles were then dried in 
conventional oven at 343 K. The sample was denoted as ED-ZSM-5@MIL-101 after 
this step. 
4.2.4 Acid Exchange Activation 
 The ED-ZSM-5@MIL-101 was soaked in HCl ethanol solution in order to 
extract free ethylene diamine trapped in zeolite and MOF micropores. The acid 
exchange was performed in a 50 mL flask equipped with a reflux condenser and heated 
in a temperature controlled oil bath under atmospheric pressure and magnetic stirring. 
0.6 g ED-ZSM-5@MIL-101 was added to 100 mL 0.15 mol L-1 HCl ethanol solution. 
The mixture was refluxed at 363 K 3 times for a total of 6 h. The acid exchanged 
particles were washed with water and ethanol repeatedly. The sample was then dried at 
423K in vacuum oven. The sample was denoted as HCl-ED-ZSM-5@MIL-101 after 
this step. 
4.2.5 Product characterizations 
The crystalline phase of catalyst samples was determined by X-Ray powder 
diffraction (XRD) using Bruker D8 Advance Lynx Powder Diffractometer. The 
integration time was 0.3 hours and the step size was 0.032 degrees/second. The 
morphology of the samples was obtained by a scanning electron microscope (SEM, 
Hitachi SU-70). N2 adsorption-desorption measurements were carried out at 77 K on 
an Autosorb-iQ analyzer (Quantachrome Instruments), respectively. Prior to the N2 and 
Ar measurements, samples were outgas at 423 K overnight. 
 71 
 
 
4.2.6 Catalytic reaction test over ZSM-5@MIL-101 composite 
The liquid phase catalytic conversion of benzylidene malononitrile from 
malononitrile and benzaldehyde dimethyl acetal (Scheme 2-2) was performed in a 
three-necked flask equipped with a reflux condenser and heated in a temperature 
controlled oil bath under atmospheric pressure and magnetic stirring (0.5” stirring bar 
and 500 rpm stirring speed) conditions. In a typical experiment, 20 mL acetonitrile 
(99.9%, Fisher), 0.0866 g malononitrile (1.31 mmol, 99%, Sigma-Aldrich), 7.5 μL DI 
water, and 0.05 g catalyst were added into the flask in sequence. After bubbled  the 
mixture with flowing helium for 0.5 h, the flask was immersed in the oil bath preheated 
at 353 K. The reaction mixture was maintained for 0.5 h at the required reaction 
temperature and stirring conditions and then 0.2045 mL of benzaldehyde dimethyl 
acetal (1.36 mmol) was added. This moment of the addition was taken as the initial 
reaction time. Liquid samples were withdrawn at regular intervals and analyzed by the 
gas chromatograph (Agilent 7890A) equipped with a methyl-siloxane capillary column 
(HP-1, 50.0 m x 320 μm x 0.52 μm) connected to a flame ionization detector (FID). 
4.3 Results and Discussion 
The morphology of ZSM-5, MIL-101, and ZSM-5@MIL-101 composite 
particles were observed with SEM. Figure 4-1 (A) shows the representative SEM image 
of ZSM-5 particles. The commercial ZSM-5 particles have a broad size distribution 
with an average size of 450 nm. Figure 4-1 (B) shows the representative SEM image 
of MIL-101 particles. The MIL-101 particles don’t have a certain shape and aggregate 
 72 
 
into large particles. The as-synthesized ZSM-5@MIL-101 core-shell composite is 
shown in Figure 4-1 (C), showing a mixture of particles with different sizes. The 
average particle size was increased to 550nm, showing the growth of MIL-101 shell 
onto the ZSM-5 core. The morphology of the core-shell structured composite differs 
with the ZSM-5@UiO-66 because of MIL-101 in this synthesis method doesn’t have a 
well-defined crystal shape. 
 
 
Figure 4-1. SEM images of (A) commercial ZSM-5 zeolite, (B) MIL-101 MOF, and 
(C) ZSM-5@MIL-101. 
 
Powder X-ray diffraction was applied to confirm the composition and 
crystallinity of the particles. Figure 4-2 shows the XRD patterns of the as-synthesized 
ZSM-5, MIL-101 and ZSM-5@MIL-101 particles, respectively. Both ZSM-5 (a) and 
MIL-101 (b) are crystallized, resembling the characteristic of a crystalline ZSM-5 and 
MIL-101 reported in literature. The ZSM-5@MIL-101 (c) composite consists of 
diffraction peaks from both MIL-101 and ZSM-5, suggesting the presence of both 
phases in the composite materials. In addition, the absence of new diffraction peaks or 
broadening of characteristic peaks of ZSM-5 or MIL-101 indicate no other structure 
forms and deterioration of the crystalline phases in the synthesis conditions. 
 73 
 
5 10 15 20 25 30
 
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2(degree)
(a)
 
Figure 4-2. XRD patterns of (a) ZSM-5, (b) MIL-101 and (c) ZSM-5@MIL-101, 
respectively. 
 
N2 adsorption-desorption isotherms (Figure 4-3) were used to characterize the 
textural properties of the samples. The surface areas of MIL-101, ZSM-5, ZSM-
5@MIL-101 and ED-ZSM-5@MIL-101 calculated by the multipoint BET method 
were 1580 m2/g, 459 m2/g, 422 m2/g and 351m2/g, respectively. The total pore volumes 
of aforementioned samples calculated at P/P0=0.95 were 0.91 mL/g, 0.27 mL/g, 0.33 
mL/g and 0.23mL/g, respectively. The surface area and total pore volume of core-shell 
composite dropped dramatically from its parenting materials, indicating intergrowth of 
these two materials or corruption of ZSM-5 micropores by TMAOH in the synthesis 
solution. The surface area and total pore volume decreased after adding ethylene 
diamine. 
 74 
 
0.0 0.2 0.4 0.6 0.8 1.0
0
200
400
600
800
N
2
 
v
o
l
u
m
e
 
a
d
s
o
r
b
e
d
 
(
c
m
3
g
-
1
 
S
T
P
)
P/P
0
 MIL-101
 Commercial ZSM-5
 ZSM-5@MIL-101
 ED-ZSM-5@MIL-101
Figure 4-3. N2 adsorption-desorption isotherms of MIL-101, ZSM-5, ZSM-5@MIL-
101, and ED-ZSM-5@MIL-101, respectively. 
 
The catalytic activity of the ZSM-5@MIL-101 was studied in the cascade 
reactions shown in Scheme 2-2. The first reaction step requires acid sites which can be 
supplied by the ZSM-5 core, while the second step involves basic sites which come 
from the amine groups in the MIL-101 shell. The composite after adding ethylene 
diamine was treated with 0.15M HCl ethanol solution and evacuated at 473 K. The 
reaction results are shown in Figure 4-4 with the molar fraction of each component 
versus reaction time. The reactant benzaldehyde dimethyl acetal was consumed 
completely at the beginning of the reaction. The TMAOH in the synthesis solution may 
cause desilication to the ZSM-5 core, resulting in rise of framework Al content and 
acidity. 
 75 
 
0 5 10 15 20 25
0
20
40
60
80
100
M
o
l
a
r
 
f
r
a
c
t
i
o
n
 
(
%
)
 
Time (h)
 Benzaldehyde Dimethylacetal
 Benzaldehyde
 Benzylidene Malononitrile
 
Figure 4-4. Catalytic reaction results of ZSM-5@MIL-101. Molar fraction of 
benzaldehyde dimethyl acetal, benzaldehyde and benzylidene malononitrile versus 
reaction time. 
4.4 Conclusions 
The core-shell composite ZSM-5@MIL-101 was synthesized using the same 
procedure as that of ZSM-5@UiO-66. The morphologies of ZSM-5, MIL-101, and 
ZSM-5@MIL-101 composite were observed by SEM. The crystallinity of the samples 
was confirmed by XRD. Textural properties of the samples were extracted from N2 
adsorption-desorption isotherms, showing a decrease of surface area and pore volume 
of the composite from its parenting materials. Post-synthetic modification with 
ethylene diamine in the MIL-101 framework incorporated amine groups into the 
composite. The acidity in ZSM-5 generated by aluminum in the tetrahedral site of the 
zeolite framework and basicity in MIL-101 originated from the amine groups enabled 
 76 
 
ZSM-5@MIL-101 composite acid-base bifunctionality for catalytic cascade reactions. 
The reaction results showed strong acidity compared to its basicity. 
  
 77 
 
Chapter 5: Conclusions and Future Work 
5.1 Conclusions 
In conclusion, zeolite@MOF core-shell composites were synthesized by 
solvothermal growth of UiO-66, MIL-101 and UiO-66-NH2 on the surface of ZSM-5 
particles that were pre-synthesized via hydrothermal crystallization. Postsynthetic 
modification of the UiO-66 and MIL-101 framework incorporated amine groups in the 
metal clusters. Presynthetic modification was used to incorporate amine groups in UiO-
66-NH2 on the organic linkers. The acidity in ZSM-5 generated by aluminum in the 
tetrahedral site of the zeolite framework and basicity in MOFs originated from the 
amine groups enabled ZSM-5@MOF composites acid-base bifunctionality for catalytic 
cascade reactions. 
The synthesis of benzylidene malononitrile from malononitrile and 
benzaldehyde dimethyl acetal, a process involving the hydrolysis of the acetal 
catalyzed by the Brønsted acid sites in zeolite, followed by a Knoevenagel 
condensation reaction catalyzed by the basic sites in MOF confirmed the bifunctional 
activity of the zeolite@MOF composites. The present work is the first example of 
synthesizing zeolite@MOF core-shell composites and exploring their applications as 
bifunctional catalysts in one-pot cascade reactions. This study is an important platform 
towards zeolite@MOF nanoporous composite systems that integrate the advantages of 
thermal, mechanical and structural stability of inorganic zeolites and functional and 
structural flexibility of MOFs for a variety of applications in the future. 
 78 
 
5.2 Future Work 
5.2.1 Mechanism investigation on growth of MOFs on zeolite surface 
The future works of this thesis as extensions contains several parts. The first 
part should be the insight on the growth mechanism for formation of MOF on the 
zeolite surface. In this thesis, a hypothesis was made that the similarity of lattice 
parameters between MOF and zeolite and the heteroatoms in zeolite framework (Al) 
could facilitate the growth of MOF around zeolite. In order to prove the hypothesis and 
to generate more universal synthesis methods for zeolite@MOF composites, the 
validity of the two factors should be investigated in detail.  
In case of applications that require shape selectivity of both MOF and zeolite, 
full coverage of MOF on zeolite is desired. The surface modification of zeolite with 
analogs of MOF building blocks (functional groups with amine or carboxylic acid) is a 
promising approach to achieve this goal. 
5.2.2 Optimization the functionalization process of zeolite@MOF composites  
The functionalization of zeolite@MOF composites can be achieved by pre-
/post- synthetic modification, which has been illustrated in this thesis. The 
postsynthetic modification, however, impaired the acidity in ZSM-5. To solve this 
problem, alternative systematic routes should be explored for functionalizing the 
composites. The combination of presynthetic and postsynthetic modification, or 
introduction of postsynthetic deprotection could endow the composites bifunctionality 
without losing the intrinsic acidity of ZSM-5. 
 79 
 
The effect of geometry of the core-shell composites on the catalytic reaction 
can be studied by changing the core size and shell thickness. The zeolite core size can 
be controlled by hydrothermal synthesis conditions (temperature, duration) of ZSM-5. 
The shell thickness can be changed in various ways. Usually it’s hard to increase the 
thickness by simply extending the reaction time or changing the concentration. The 
layer-by-layer synthesis method or multiple growth cycles can be used to increase the 
MOF thickness. 
5.2.3 Shape selectivity of zeolite@MOF composites in other applications 
The zeolite@MOF core-shell composites are promising materials in many 
potential applications. Their bifunctionality has been demonstrated by the probe 
cascade reactions. It can be readily expanded to other acid-base catalyzed cascade 
reactions. Other functional groups can be introduced into the composites for extra 
applications. Another application being considered is using seamless MOF shell as the 
molecular sieve to screen the molecules going to the catalytic sites in zeolite core. 
Although zeolite itself has shape selective features, the external active sites will make 
negative contribution especially in mesoporous zeolites. Flimsy MOFs can be 
introduced to the core-shell structure which would decompose easily under certain 
conditions. This can be used in drug or chemical delivery systems.  
  
 80 
 
References 
 
1. McNaught, A.D. and A. Wilkinson, IUPAC Compendium of chemical 
terminology, 2000, International Union of Pure and Applied Chemistry. 
2. Morris, R.E. and P.S. Wheatley, Gas Storage in Nanoporous Materials. 
Angewandte Chemie International Edition, 2008. 47(27): p. 4966-4981. 
3. Lu, G.Q., X.S. Zhao, and T.K. Wei, Nanoporous materials: science and 
engineering. Vol. 4. 2004: Imperial College Press. 
4. Minachev Kh, M. and I. Isakov Ya, Catalytic Properties of Zeolites?A General 
Review, in Molecular Sieves. 1973, American Chemical Society. p. 451-460. 
5. Kulprathipanja, S. and J. Wiley, Zeolites in industrial separation and catalysis. 
2010: Wiley Online Library. 
6. Corma, A., H. García, and F.X. Llabrés i Xamena, Engineering Metal Organic 
Frameworks for Heterogeneous Catalysis. Chemical Reviews, 2010. 110(8): p. 
4606-4655. 
7. Li, J.-R., J. Sculley, and H.-C. Zhou, Metal–Organic Frameworks for 
Separations. Chemical Reviews, 2011. 112(2): p. 869-932. 
8. Jacobs, P., et al., Introduction to zeolite science and practice. 2001: Elsevier 
Science. 
9. Cronstedt, A.F., RÖN och BESKRIFNING Om en oberkant barg art, som kallas 
Zeolites. Kongl Vetenskaps Academiens Handlingar Stockholm, 1765. 17: p. 
120. 
10. Flanigen, E.M., Zeolites and molecular sieves an historical perspective. Studies 
in Surface Science and Catalysis, 1991. 58: p. 13-34. 
11. Cundy, C.S. and P.A. Cox, The hydrothermal synthesis of zeolites: history and 
development from the earliest days to the present time. Chemical Reviews, 
2003. 103(3): p. 663-702. 
12. Snyder, M.A. and M. Tsapatsis, Hierarchical Nanomanufacturing: From 
Shaped Zeolite Nanoparticles to High-Performance Separation Membranes. 
Angewandte Chemie International Edition, 2007. 46(40): p. 7560-7573. 
13. Perez-Ramirez, J., et al., Hierarchical zeolites: enhanced utilisation of 
microporous crystals in catalysis by advances in materials design. Chemical 
Society Reviews, 2008. 37(11): p. 2530-2542. 
14. Choi, M., et al., Stable single-unit-cell nanosheets of zeolite MFI as active and 
long-lived catalysts. Nature, 2009. 461(7261): p. 246-249. 
15. Baerlocher, C., L.B. McCusker, and D.H. Olson, Atlas of zeolite framework 
types. 2007: Elsevier. 
16. Gillett, S.L. Toward a Silicate-Based Molecular Nanotechnology I. 
Background and Review. in The Fifth Foresight Conference on Molecular 
Nanotechnology, Palo Alto California. 1997. 
17. Claridge, R.P., et al., Faujasite catalysis of aromatic nitrations with dinitrogen 
pentoxide. The effect of aluminium content on catalytic activity and 
regioselectivity. The nitration of pyrazole. Journal of the Chemical Society, 
Perkin Transactions 2, 2001(2): p. 197-200. 
 81 
 
18. Corma, A., et al., Modified faujasite zeolites as catalysts in organic reactions: 
Esterification of carboxylic acids in the presence of HY zeolites. Journal of 
Catalysis, 1989. 120(1): p. 78-87. 
19. Christensen, C.H., et al., Catalytic Benzene Alkylation over Mesoporous Zeolite 
Single Crystals:  Improving Activity and Selectivity with a New Family of 
Porous Materials. Journal of the American Chemical Society, 2003. 125(44): 
p. 13370-13371. 
20. Wang, D., J.H. Lunsford, and M.P. Rosynek, Characterization of a Mo/ZSM-5 
Catalyst for the Conversion of Methane to Benzene. Journal of Catalysis, 1997. 
169(1): p. 347-358. 
21. Gottardi, G. and E. Galli, Natural zeolites. 1985: Springer-Verlag Berlin. 
22. Ibrahim, S.A., Synthesis and Characterization of Zeolites from Sodium 
Aluminosilicate Solution, 2007, Universiti Sains Malaysia. 
23. Dyer, A., An introduction to zeolite molecular sieves. 1988. Medium: X; Size: 
Pages: (149 p). 
24. Meier, W.M. and D.H. Olson, Atlas of zeolite structure types. Vol. 26. 1987: 
Butterworths London etc. 
25. Zhang, L., et al., Organic template-free synthesis of ZSM-5/ZSM-11 co-
crystalline zeolite. Microporous and Mesoporous Materials, 2012. 147(1): p. 
117-126. 
26. Barrer, R.M., Hydrothermal chemistry of zeolites. 1982. 
27. Li, G., E. Kikuchi, and M. Matsukata, ZSM-5 zeolite membranes prepared from 
a clear template-free solution. Microporous and Mesoporous Materials, 2003. 
60(1–3): p. 225-235. 
28. Song, J., et al., Organic Template Free Synthesis of Aluminosilicate Zeolite 
ECR-1. Chemistry of Materials, 2006. 18(12): p. 2775-2777. 
29. Cundy, C.S., Microwave techniques in the synthesis and modification of zeolite 
catalysts. A review. Collection of Czechoslovak chemical communications, 
1998. 63(11): p. 1699-1723. 
30. Arafat, A., et al., Microwave preparation of zeolite Y and ZSM-5. Zeolites, 
1993. 13(3): p. 162-165. 
31. Stach, H., et al., Adsorption equilibria of hydrocarbons on highly dealuminated 
zeolites. Zeolites, 1986. 6(2): p. 74-90. 
32. Corma, A., et al., Determination of the Pore Topology of Zeolite IM-5 by Means 
of Catalytic Test Reactions and Hydrocarbon Adsorption Measurements. 
Journal of Catalysis, 2000. 189(2): p. 382-394. 
33. Haag, W.O., R.M. Lago, and P.B. Weisz, Transport and reactivity of 
hydrocarbon molecules in a shape-selective zeolite. Faraday Discussions of the 
Chemical Society, 1981. 72(0): p. 317-330. 
34. Yan, T.Y., Separation of p-xylene and ethylbenzene from C8 aromatics using 
medium-pore zeolites. Industrial & Engineering Chemistry Research, 1989. 
28(5): p. 572-576. 
35. Santacesaria, E., et al., Separation of xylenes on Y zeolites. 1. Determination of 
the adsorption equilibrium parameters, selectivities, and mass transfer 
coefficients through finite bath experiments. Industrial & Engineering 
Chemistry Process Design and Development, 1982. 21(3): p. 440-445. 
 82 
 
36. Kazansky, V.B., The Catalytic Site from a Chemical Point of View, in Studies 
in Surface Science and Catalysis, M.S.H.G.K. J.C. Jansen and J. Weitkamp, 
Editors. 1994, Elsevier. p. 251-272. 
37. Furukawa, H., et al., The Chemistry and Applications of Metal-Organic 
Frameworks. Science, 2013. 341(6149): p. 974. 
38. Stock, N. and S. Biswas, Synthesis of Metal-Organic Frameworks (MOFs): 
Routes to Various MOF Topologies, Morphologies, and Composites. Chemical 
Reviews, 2011. 112(2): p. 933-969. 
39. Hoskins, B.F. and R. Robson, Infinite polymeric frameworks consisting of three 
dimensionally linked rod-like segments. Journal of the American Chemical 
Society, 1989. 111(15): p. 5962-5964. 
40. Gable, R.W., B.F. Hoskins, and R. Robson, A new type of interpenetration 
involving enmeshed independent square grid sheets. The structure of diaquabis-
(4,4[prime or minute]-bipyridine)zinc hexafluorosilicate. Journal of the 
Chemical Society, Chemical Communications, 1990(23): p. 1677-1678. 
41. Gable, R.W., B.F. Hoskins, and R. Robson, Synthesis and structure of 
[NMe4][CuPt (CN) 4]: an infinite three-dimensional framework related to PtS 
which generates intersecting hexagonal channels of large cross section. Journal 
of the Chemical Society, Chemical Communications, 1990(10): p. 762-763. 
42. Aharoni, S.M. and S.F. Edwards, Rigid polymer networks. Vol. 118. 1994: 
Springer-Verlag. 
43. Burch, R.R., Oxidation-reduction reactions for preparation of 
[Ti(OC6H4O)2]n and related metalloquinone polymers: hybrid inorganic-
organic metal oxides. Chemistry of Materials, 1990. 2(6): p. 633-635. 
44. Chapman, O.L., Diamondoid polymeric compositions, 1991, Google Patents. 
45. Webster, O.W., et al., Hypercrosslinked rigid-rod polymers. Makromolekulare 
Chemie. Macromolecular Symposia, 1992. 54-55(1): p. 477-482. 
46. Yaghi, O.M., G. Li, and H. Li, Selective binding and removal of guests in a 
microporous metal–organic framework. Nature, 1995. 378(6558): p. 703-706. 
47. Yaghi, O.M. and H. Li, Hydrothermal Synthesis of a Metal-Organic 
Framework Containing Large Rectangular Channels. Journal of the American 
Chemical Society, 1995. 117(41): p. 10401-10402. 
48. Yaghi, O.M., et al., Selective Guest Binding by Tailored Channels in a 3-D 
Porous Zinc(II)−Benzenetricarboxylate Network. Journal of the American 
Chemical Society, 1997. 119(12): p. 2861-2868. 
49. Li, H., et al., Establishing Microporosity in Open Metal−Organic 
Frameworks:  Gas Sorption Isotherms for Zn(BDC) (BDC = 1,4-
Benzenedicarboxylate). Journal of the American Chemical Society, 1998. 
120(33): p. 8571-8572. 
50. Furukawa, H., et al., The Chemistry and Applications of Metal-Organic 
Frameworks. Science, 2013. 341(6149). 
51. Tranchemontagne, D.J., et al., Secondary building units, nets and bonding in 
the chemistry of metal-organic frameworks. Chemical Society Reviews, 2009. 
38(5): p. 1257-1283. 
52. Li, H., et al., Design and synthesis of an exceptionally stable and highly porous 
metal-organic framework. Nature, 1999. 402(6759): p. 276-279. 
 83 
 
53. Chui, S.S.-Y., et al., A Chemically Functionalizable Nanoporous Material 
[Cu3(TMA)2(H2O)3]n. Science, 1999. 283(5405): p. 1148-1150. 
54. Tian, Y.-Q., et al., [Co5(im)10⋅2 MB]∞: A Metal-Organic Open-Framework 
with Zeolite-Like Topology. Angewandte Chemie, 2002. 114(8): p. 1442-1444. 
55. Phan, A., et al., Synthesis, Structure, and Carbon Dioxide Capture Properties 
of Zeolitic Imidazolate Frameworks. Accounts of Chemical Research, 2009. 
43(1): p. 58-67. 
56. Huang, X., J. Zhang, and X. Chen, [Zn(bim)2] · (H2O)1.67: A metal-organic 
open-framework with sodalite topology. Chinese Science Bulletin, 2003. 
48(15): p. 1531-1534. 
57. Venna, S.R. and M.A. Carreon, Highly Permeable Zeolite Imidazolate 
Framework-8 Membranes for CO2/CH4 Separation. Journal of the American 
Chemical Society, 2009. 132(1): p. 76-78. 
58. Férey, G., et al., A Chromium Terephthalate-Based Solid with Unusually Large 
Pore Volumes and Surface Area. Science, 2005. 309(5743): p. 2040-2042. 
59. Férey, G., et al., A Hybrid Solid with Giant Pores Prepared by a Combination 
of Targeted Chemistry, Simulation, and Powder Diffraction. Angewandte 
Chemie, 2004. 116(46): p. 6456-6461. 
60. Cavka, J.H., et al., A New Zirconium Inorganic Building Brick Forming Metal 
Organic Frameworks with Exceptional Stability. Journal of the American 
Chemical Society, 2008. 130(42): p. 13850-13851. 
61. Pan, Y. and Z. Lai, Sharp separation of C2/C3 hydrocarbon mixtures by zeolitic 
imidazolate framework-8 (ZIF-8) membranes synthesized in aqueous solutions. 
Chemical Communications, 2011. 47(37): p. 10275-10277. 
62. Rosi, N.L., et al., Hydrogen Storage in Microporous Metal-Organic 
Frameworks. Science, 2003. 300(5622): p. 1127-1129. 
63. Cravillon, J., et al., Rapid Room-Temperature Synthesis and Characterization 
of Nanocrystals of a Prototypical Zeolitic Imidazolate Framework. Chemistry 
of Materials, 2009. 21(8): p. 1410-1412. 
64. Zhuang, J.-L., et al., Rapid Room-Temperature Synthesis of Metal–Organic 
Framework HKUST-1 Crystals in Bulk and as Oriented and Patterned Thin 
Films. Advanced Functional Materials, 2011. 21(8): p. 1442-1447. 
65. Mueller, U., et al., Method for electrochemical production of a crystalline 
porous metal organic skeleton material, 2005, Google Patents. 
66. Jhung, S.H., J. Lee, and J. Chang, Microwave synthesis of a nanoporous hybrid 
material, chromium trimesate. BULLETIN-KOREAN CHEMICAL 
SOCIETY, 2005. 26(6): p. 880. 
67. Pichon, A., A. Lazuen-Garay, and S.L. James, Solvent-free synthesis of a 
microporous metal-organic framework. CrystEngComm, 2006. 8(3): p. 211-
214. 
68. Qiu, L.-G., et al., Facile synthesis of nanocrystals of a microporous metal-
organic framework by an ultrasonic method and selective sensing of 
organoamines. Chemical Communications, 2008(31): p. 3642-3644. 
69. Richter, I., M. Schubert, and U. Mueller, Porous metal organic framework 
based on pyrroles and pyridinones, 2007, Google Patents. 
 84 
 
70. Schlesinger, M., et al., Evaluation of synthetic methods for microporous metal–
organic frameworks exemplified by the competitive formation of 
[Cu2(btc)3(H2O)3] and [Cu2(btc)(OH)(H2O)]. Microporous and Mesoporous 
Materials, 2010. 132(1–2): p. 121-127. 
71. Klinowski, J., et al., Microwave-Assisted Synthesis of Metal-Organic 
Frameworks. Dalton Transactions, 2011. 40(2): p. 321-330. 
72. Horcajada, P., et al., Porous metal-organic-framework nanoscale carriers as a 
potential platform for drug delivery and imaging. Nature materials, 2010. 9(2): 
p. 172-178. 
73. Fernández-Bertran, J.F., Mechanochemistry: an overview. Pure and applied 
chemistry, 1999. 71(4): p. 581-586. 
74. Son, W.-J., et al., Sonochemical synthesis of MOF-5. Chemical 
Communications, 2008(47): p. 6336-6338. 
75. Deng, H., et al., Multiple Functional Groups of Varying Ratios in Metal-
Organic Frameworks. Science, 2010. 327(5967): p. 846-850. 
76. Wang, Z. and S.M. Cohen, Postsynthetic modification of metal-organic 
frameworks. Chemical Society Reviews, 2009. 38(5): p. 1315-1329. 
77. Cohen, S.M., Modifying MOFs: new chemistry, new materials. Chemical 
Science, 2010. 1(1): p. 32-36. 
78. Tanabe, K.K. and S.M. Cohen, Postsynthetic modification of metal-organic 
frameworks-a progress report. Chemical Society Reviews, 2011. 40(2): p. 498-
519. 
79. Cohen, S.M., Postsynthetic methods for the functionalization of metal–organic 
frameworks. Chemical reviews, 2011. 112(2): p. 970-1000. 
80. Yamada, T. and H. Kitagawa, Protection and Deprotection Approach for the 
Introduction of Functional Groups into Metal−Organic Frameworks. Journal 
of the American Chemical Society, 2009. 131(18): p. 6312-6313. 
81. Deshpande, R.K., J.L. Minnaar, and S.G. Telfer, Thermolabile Groups in 
Metal–Organic Frameworks: Suppression of Network Interpenetration, Post-
Synthetic Cavity Expansion, and Protection of Reactive Functional Groups. 
Angewandte Chemie International Edition, 2010. 49(27): p. 4598-4602. 
82. Chen, B., et al., A Microporous Metal–Organic Framework for Gas-
Chromatographic Separation of Alkanes. Angewandte Chemie, 2006. 118(9): 
p. 1418-1421. 
83. Hamon, L., et al., Co-adsorption and Separation of CO2−CH4 Mixtures in the 
Highly Flexible MIL-53(Cr) MOF. Journal of the American Chemical Society, 
2009. 131(47): p. 17490-17499. 
84. Bae, T.-H., et al., A High-Performance Gas-Separation Membrane Containing 
Submicrometer-Sized Metal–Organic Framework Crystals. Angewandte 
Chemie International Edition, 2010. 49(51): p. 9863-9866. 
85. Farha, O.K., et al., De novo synthesis of a metal–organic framework material 
featuring ultrahigh surface area and gas storage capacities. Nature chemistry, 
2010. 2(11): p. 944-948. 
86. Lee, J., et al., Metal–organic framework materials as catalysts. Chemical 
Society Reviews, 2009. 38(5): p. 1450-1459. 
 85 
 
87. Shultz, A.M., et al., A Catalytically Active, Permanently Microporous MOF 
with Metalloporphyrin Struts. Journal of the American Chemical Society, 2009. 
131(12): p. 4204-4205. 
88. Noro, S.-i., et al., A New, Methane Adsorbent, Porous Coordination Polymer 
[{CuSiF6(4,4′-bipyridine)2}n]. Angewandte Chemie International Edition, 
2000. 39(12): p. 2081-2084. 
89. Ma, S., et al., Metal-Organic Framework from an Anthracene Derivative 
Containing Nanoscopic Cages Exhibiting High Methane Uptake. Journal of the 
American Chemical Society, 2007. 130(3): p. 1012-1016. 
90. Zhao, X., et al., Hysteretic Adsorption and Desorption of Hydrogen by 
Nanoporous Metal-Organic Frameworks. Science, 2004. 306(5698): p. 1012-
1015. 
91. Li, Y. and R.T. Yang, Significantly Enhanced Hydrogen Storage in 
Metal−Organic Frameworks via Spillover. Journal of the American Chemical 
Society, 2005. 128(3): p. 726-727. 
92. Ordoñez, M.J.C., et al., Molecular sieving realized with ZIF-8/Matrimid® 
mixed-matrix membranes. Journal of Membrane Science, 2010. 361(1–2): p. 
28-37. 
93. Tanaka, K., et al., Highly efficient chromatographic resolution of sulfoxides 
using a new homochiral MOF-silica composite. Chemical Communications, 
2012. 48(68): p. 8577-8579. 
94. Efraty, A. and I. Feinstein, Catalytic hydrogenation and isomerization of 1-
hexene with [RhCl(CO)(1,4-(CN)2C6H4)]n in the dark and under irradiation. 
Inorganic Chemistry, 1982. 21(8): p. 3115-3118. 
95. Tannenbaum, R., Three-Dimensional Coordination Polymers of 
Ruthenium(2+) with 1,4-Diisocyanobenzene Ligands and Their Catalytic 
Activity. Chemistry of Materials, 1994. 6(4): p. 550-555. 
96. Fujita, M., et al., Preparation, Clathration Ability, and Catalysis of a Two-
Dimensional Square Network Material Composed of Cadmium(II) and 4,4'-
Bipyridine. Journal of the American Chemical Society, 1994. 116(3): p. 1151-
1152. 
97. Gomez-Lor, B., et al., In2(OH)3(BDC)1.5 (BDC = 1,4-Benzendicarboxylate):  
An In(III) Supramolecular 3D Framework with Catalytic Activity. Inorganic 
Chemistry, 2002. 41(9): p. 2429-2432. 
98. Kato, C.N., et al., Microporous dinuclear copper(II) trans-1,4-
cyclohexanedicarboxylate: heterogeneous oxidation catalysis with hydrogen 
peroxide and X-ray powder structure of peroxo copper(II) intermediate. Journal 
of Catalysis, 2005. 230(1): p. 226-236. 
99. Yu, Z.-T., et al., Construction of a microporous inorganic-organic hybrid 
compound with uranyl units. Chemical Communications, 2004(16): p. 1814-
1815. 
100. Hwang, Y.K., et al., Amine Grafting on Coordinatively Unsaturated Metal 
Centers of MOFs: Consequences for Catalysis and Metal Encapsulation. 
Angewandte Chemie-international Edition, 2008. 47(22): p. 4144-4148. 
101. Hasegawa, S., et al., Three-Dimensional Porous Coordination Polymer 
Functionalized with Amide Groups Based on Tridentate Ligand:  Selective 
 86 
 
Sorption and Catalysis. Journal of the American Chemical Society, 2007. 
129(9): p. 2607-2614. 
102. Seo, J.S., et al., A homochiral metal–organic porous material for 
enantioselective separation and catalysis. Nature, 2000. 404(6781): p. 982-986. 
103. Uemura, T., N. Yanai, and S. Kitagawa, Polymerization reactions in porous 
coordination polymers. Chemical Society Reviews, 2009. 38(5): p. 1228-1236. 
104. Banerjee, M., et al., Postsynthetic Modification Switches an Achiral Framework 
to Catalytically Active Homochiral Metal−Organic Porous Materials. Journal 
of the American Chemical Society, 2009. 131(22): p. 7524-7525. 
105. Esken, D., et al., Au@ZIFs: Stabilization and Encapsulation of Cavity-Size 
Matching Gold Clusters inside Functionalized Zeolite Imidazolate 
Frameworks, ZIFs. Chemistry of Materials, 2010. 22(23): p. 6393-6401. 
106. Aguado, S., et al., Tuning the activity by controlling the wettability of MOF 
eggshell catalysts: A quantitative structure–activity study. Journal of Catalysis, 
2011. 284(2): p. 207-214. 
107. Sorribas, S., et al., Ordered mesoporous silica-(ZIF-8) core-shell spheres. 
Chemical Communications, 2012. 48(75): p. 9388-9390. 
108. Yang, S.J., et al., Preparation and Enhanced Hydrostability and Hydrogen 
Storage Capacity of CNT@MOF-5 Hybrid Composite. Chemistry of Materials, 
2009. 21(9): p. 1893-1897. 
109. Zhan, W.-w., et al., Semiconductor@Metal–Organic Framework Core–Shell 
Heterostructures: A Case of ZnO@ZIF-8 Nanorods with Selective 
Photoelectrochemical Response. Journal of the American Chemical Society, 
2013. 135(5): p. 1926-1933. 
110. Zlotea, C., et al., Pd Nanoparticles Embedded into a Metal-Organic 
Framework: Synthesis, Structural Characteristics, and Hydrogen Sorption 
Properties. Journal of the American Chemical Society, 2010. 132(9): p. 2991-
2997. 
111. Dhakshinamoorthy, A. and H. Garcia, Catalysis by metal nanoparticles 
embedded on metal-organic frameworks. Chemical Society Reviews, 2012. 
41(15): p. 5262-5284. 
112. Houk, R.J.T., et al., Silver Cluster Formation, Dynamics, and Chemistry in 
Metal−Organic Frameworks. Nano Letters, 2009. 9(10): p. 3413-3418. 
113. Lu, G., et al., Imparting functionality to a metal–organic framework material 
by controlled nanoparticle encapsulation. Nature chemistry, 2012. 4(4): p. 310-
316. 
114. Lohe, M.R., et al., Heating and separation using nanomagnet-functionalized 
metal-organic frameworks. Chemical Communications, 2011. 47(11): p. 3075-
3077. 
115. Xing, L., et al., Coordination Polymer Coated Mesoporous Silica 
Nanoparticles for pH-Responsive Drug Release. Advanced Materials, 2012. 
24(48): p. 6433-6437. 
116. Jo, C., H.J. Lee, and M. Oh, One-Pot Synthesis of Silica@Coordination 
Polymer Core–Shell Microspheres with Controlled Shell Thickness. Advanced 
Materials, 2011. 23(15): p. 1716-1719. 
 87 
 
117. Lee, H.J., W. Cho, and M. Oh, Advanced fabrication of metal-organic 
frameworks: template-directed formation of polystyrene@ZIF-8 core-shell and 
hollow ZIF-8 microspheres. Chemical Communications, 2012. 48(2): p. 221-
223. 
118. Nozik, A.J., et al., Semiconductor Quantum Dots and Quantum Dot Arrays and 
Applications of Multiple Exciton Generation to Third-Generation Photovoltaic 
Solar Cells. Chemical Reviews, 2010. 110(11): p. 6873-6890. 
119. Zhu, Q.-L. and Q. Xu, Metal-organic framework composites. Chemical Society 
Reviews, 2014: p. Accepted. 
120. Ramos-Fernandez, E.V., et al., MOFs meet monoliths: Hierarchical structuring 
metal organic framework catalysts. Applied Catalysis A-general, 2011. 391(1–
2): p. 261-267. 
121. Lai, Z., et al., Microstructural Optimization of a Zeolite Membrane for Organic 
Vapor Separation. Science, 2003. 300(5618): p. 456-460. 
122. Chen, N.Y. and W.J. Reagan, Evidence of autocatalysis in methanol to 
hydrocarbon reactions over zeolite catalysts. Journal of Catalysis, 1979. 59(1): 
p. 123-129. 
123. Martínez, C. and A. Corma, Inorganic molecular sieves: Preparation, 
modification and industrial application in catalytic processes. Coordination 
Chemistry Reviews, 2011. 255(13–14): p. 1558-1580. 
124. Xu, R., et al., From Zeolites to Porous MOF Materials-the 40th Anniversary of 
International Zeolite Conference: Proceedings of the 15th International Zeolite 
Conference, Beijing, PR China, 12-17th August 2007. Vol. 170. 2007: Elsevier. 
125. Argauer, R.J. and G.R. Landolt, Crystalline zeolite zsm-5 and method of 
preparing the same, 1972, US Patent 3,702,886. 
126. Olson, D., et al., Crystal structure and structure-related properties of ZSM-5. 
J. Phys. Chem., 1981. 85(15): p. 2238-2243. 
127. Quann, R.J., et al., Chemistry of olefin oligomerization over ZSM-5 catalyst. 
Industrial & Engineering Chemistry Research, 1988. 27(4): p. 565-570. 
128. Wu, E.L., et al., ZSM-5-type materials. Factors affecting crystal symmetry. J. 
Phys. Chem., 1979. 83(21): p. 2777-2781. 
129. Liu, S., et al., Fast Syntheses of MOFs Using Nanosized Zeolite Crystal Seeds 
In Situ Generated from Microsized Zeolites. Cryst. Growth Des., 2013. 13(7): 
p. 2697-2702. 
130. Valenzano, L., et al., Disclosing the Complex Structure of UiO-66 Metal 
Organic Framework: A Synergic Combination of Experiment and Theory. 
Chemistry of Materials, 2011. 23(7): p. 1700-1718. 
131. Flanigen Edith, M., H. Khatami, and A. Szymanski Herman, Infrared 
Structural Studies of Zeolite Frameworks, in Molecular Sieve Zeolites-I. 1974, 
American Chemical Society. p. 201-229. 
132. Giorgini, M.G., et al., Vibrational spectra and assignments of ethylene-diamine 
and its deuterated derivatives. Journal of Raman Spectroscopy, 1983. 14(1): p. 
16-21. 
133. Yang, J., et al., Synthesis of metal–organic framework MIL-101 in TMAOH-
Cr(NO3)3-H2BDC-H2O and its hydrogen-storage behavior. Microporous and 
Mesoporous Materials, 2010. 130(1–3): p. 174-179.