10536 Chem. Commun., 2011, 47, 10536–10547 This journal is c The Royal Society of Chemistry 2011 Cite this: Chem. Commun., 2011, 47, 10536–10547 Recent advances in hierarchically structured zeolites: synthesis and material performances Zi Le Hua, Jian Zhou and Jian Lin Shi* Received 14th January 2011, Accepted 10th June 2011 DOI: 10.1039/c1cc10261c Hierarchically structured zeolites (HSZs) have attracted increasing attention in the last few years, thanks to their unique hierarchical porous structures combining micro- and mesoporosity and superior material performances, especially in the bulky molecules-involved catalysis and adsorption applications. In this Feature Article, the recent advances in the HSZs synthetic methodologies and material performances in catalysis are overviewed. Further, some perspectives for the future development of HSZs are discussed. 1. Introduction Zeolites are an important class of crystalline porous materials with cage- or channel-like structures. Due to their well-defined micropore sizes for molecular shape selectivity, large specific surface areas, intrinsic acidity, and high (hydro)thermal and chemical stability, they have shown great (or potential) applications in many modern industrial processes related to catalysis, adsorption, and separation. However, the small sizes (typically o1.2 nm) of the inherent intracrystalline micropore channels or windows of pure zeolites are becoming a more and more significant obstacle for their applications in bulky molecules-involved processes. The diffusion limitation of relatively large molecules in the micropore channels would result in a poor access of reactants to the zeolite active sites, and more severely, the frequent blocking of the diffusion path and the fast deactivation of the zeolites. To solve the diffusion problems of guest species in zeolites, ordered mesoporous materials (OMMs) with adjustable larger pore sizes (2–30 nm), such as M41s, 1 SBA-n, 2 and MSU-x, 3 have been successively invented since the 1990s. However, until now, their practical applications are still far from the extensive success, especially in the petrochemical processes, owing to their amorphous frameworks and the resultant low stability and lack of (strong) acidity. Around 2001, some progress in the templating synthesis of highly stable and acidic mesostructured materials was made through the incorporation of zeolite secondary building units (SBU) in the mesoporous frameworks, whose precursors could be the aged zeolite State Key Lab of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050, P. R. China. E-mail: [email protected]; Fax: +86-21-52413122 Zi Le Hua Zile Hua obtained his MS degree from South China University of Technology in 1999 and his PhD degree from Shanghai Institute of Ceramics, Chinese Academy of Sciences (SICCAS) in 2002. Then he joined the State Key Lab of High Performance Ceramics and Superfine Microstructure at SICCAS. In 2004, he worked at University of Manchester as a visiting scholar on the solvothermal synthesis of yttria-stabilized zirconia. He is now an associate professor at SICCAS. His current research interests include hierarchical porous materials, mesoporous thin films and environmental catalysis. Jian Zhou Jian Zhou obtained his BS degree from China University of Geosciences in 2006, and then continued his postgraduate study under the supervision of Prof. Jianlin Shi in the State Key Lab of High Performance Ceramics and Superfine Microstructure at SICCAS. His main research topic is the preparation and catalytic applications of hierarchical micro-/mesoporous materials. ChemComm Dynamic Article Links www.rsc.org/chemcomm FEATURE ARTICLE Downloaded by Shanghai Institute of Ceramics, CAS on 10 April 2012 Published on 01 July 2011 on http://pubs.rsc.org | doi:10.1039/C1CC10261C View Online / Journal Homepage / Table of Contents for this issue
12
Embed
ChemComm Dynamic Article Links · This ournal is c The Royal Society of Chemistry 2011 Chem. Commun.,2011,47, 1053610547 10537 synthesis sols4,5 or the destructive products of pre-synthesized
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
10536 Chem. Commun., 2011, 47, 10536–10547 This journal is c The Royal Society of Chemistry 2011
Cite this: Chem. Commun., 2011, 47, 10536–10547
Recent advances in hierarchically structured zeolites: synthesis and
material performances
Zi Le Hua, Jian Zhou and Jian Lin Shi*
Received 14th January 2011, Accepted 10th June 2011
DOI: 10.1039/c1cc10261c
Hierarchically structured zeolites (HSZs) have attracted increasing attention in the last few years,
thanks to their unique hierarchical porous structures combining micro- and mesoporosity and
superior material performances, especially in the bulky molecules-involved catalysis and
adsorption applications. In this Feature Article, the recent advances in the HSZs synthetic
methodologies and material performances in catalysis are overviewed. Further, some perspectives
for the future development of HSZs are discussed.
1. Introduction
Zeolites are an important class of crystalline porous materials
with cage- or channel-like structures. Due to their well-defined
micropore sizes for molecular shape selectivity, large specific
surface areas, intrinsic acidity, and high (hydro)thermal
and chemical stability, they have shown great (or potential)
applications in many modern industrial processes related to
catalysis, adsorption, and separation. However, the small sizes
(typically o1.2 nm) of the inherent intracrystalline micropore
channels or windows of pure zeolites are becoming a more
and more significant obstacle for their applications in bulky
molecules-involved processes. The diffusion limitation of
relatively large molecules in the micropore channels would
result in a poor access of reactants to the zeolite active sites,
and more severely, the frequent blocking of the diffusion path
and the fast deactivation of the zeolites.
To solve the diffusion problems of guest species in zeolites,
ordered mesoporous materials (OMMs) with adjustable larger
pore sizes (2–30 nm), such as M41s,1 SBA-n,2 and MSU-x,3
have been successively invented since the 1990s. However,
until now, their practical applications are still far from the
extensive success, especially in the petrochemical processes,
owing to their amorphous frameworks and the resultant low
stability and lack of (strong) acidity. Around 2001, some
progress in the templating synthesis of highly stable and acidic
mesostructured materials was made through the incorporation
of zeolite secondary building units (SBU) in the mesoporous
frameworks, whose precursors could be the aged zeolite
State Key Lab of High Performance Ceramics and SuperfineMicrostructure, Shanghai Institute of Ceramics, Chinese Academy ofSciences, 1295 Dingxi Road, Shanghai 200050, P. R. China.E-mail: [email protected]; Fax: +86-21-52413122
Zi Le Hua
Zile Hua obtained his MSdegree from South ChinaUniversity of Technology in1999 and his PhD degreefrom Shanghai Institute ofCeramics, Chinese Academyof Sciences (SICCAS) in2002. Then he joined the StateKey Lab of High PerformanceCeramics and SuperfineMicrostructure at SICCAS.In 2004, he worked atUniversity of Manchester asa visiting scholar on thesolvothermal synthesis ofyttria-stabilized zirconia. He
is now an associate professor at SICCAS. His current researchinterests include hierarchical porous materials, mesoporous thinfilms and environmental catalysis.
Jian Zhou
Jian Zhou obtained his BSdegree from China Universityof Geosciences in 2006, andthen continued his postgraduatestudy under the supervision ofProf. Jianlin Shi in the StateKey Lab of High PerformanceCeramics and SuperfineMicrostructure at SICCAS.His main research topic is thepreparation and catalyticapplications of hierarchicalmicro-/mesoporous materials.
ChemComm Dynamic Article Links
www.rsc.org/chemcomm FEATURE ARTICLE
Dow
nloa
ded
by S
hang
hai I
nstit
ute
of C
eram
ics,
CA
S on
10
Apr
il 20
12Pu
blis
hed
on 0
1 Ju
ly 2
011
on h
ttp://
pubs
.rsc
.org
| do
i:10.
1039
/C1C
C10
261C
View Online / Journal Homepage / Table of Contents for this issue
selectivity, durability, and recyclability) were achieved compared
with their parent zeolites. Possible modifications induced by
the post-synthesis demetallation treatment were not limited
only to micro/mesoporous structures, but also to material
compositions and active site distributions, all of which would
cooperatively contribute to the improvement of material
performances.
In a word, whether by template synthesis or by the post-
synthetic demetallation process, a common target for HSZs
preparation is that the resultant products should be the single-
crystal(-like) materials with well-controlled and penetrating
mesoporous structures, and maximally preserved native char-
acters of pure zeolites (microporosity, acidity, and stability).
In the past decade, significant progress has been made in the
development of HSZs synthetic methodologies and material
performances, such as catalytic properties, and a number of
excellent reviews about HSZs have also been published in the
last few years.16,17,19–22 Interestingly, a very recent review,
which was given by Chal et al., outlined HSZs’ industrial
perspectives, however, no detailed information on the catalytic
performance of HSZs was addressed.22 Here, in this Feature
Article, combined with our new results on HSZs synthesis
with the ordinary cationic or copolymer surfactants as the
mesoporogens, the most recent advances in this rapidly growing
research field will be reviewed, mainly focusing on the
publications in the last three or four years. To concentrate
our reviewing and also limited by the article length, mainly
the direct synthesis of HSZs by using soft templates and
post-synthesis demetallation/desilication will be concerned in
this article.
2. Templating synthesis of HSZs
2.1 HSZs synthesized with specially designed templates
Direct synthesis of HSZs with multi-length scale templates is a
straightforward idea originated from the successful preparation
of OMMs via supramolecular micelles. However, as mentioned
Jian Lin Shi
Jianlin Shi obtained his PhDdegree in 1989 at the ShanghaiInstitute of Ceramics, ChineseAcademy of Sciences (SIC-CAS). His main researchfields include processingscience of advanced ceramics,sintering theory, inorganicnano-structured materials andmesoporous materials. Morethan 260 papers have beenpublished and these publica-tions have been cited by otherscientists for more than 3400times with an H-index of 32.Professor Jianlin Shi is now
the director of the State Key Lab of High Performance Cera-mics and Superfine Microstructure. He has been awarded ofShanghai Natural Science Prize (the first grade) and alsoreceived several other awards.
some additional moderating agents are required to get HSZs
materials with balanced performances.
In general, whether by direct synthesis or by the post-
synthetic desilication process, a suitable balance between
microporosity and mesoporosity in the resultant HSZs is very
important. In this respect, the hierarchy factor (HF) is a
simplified and effective index in evaluating the HSZs properties
or designing newly structured HSZs, in which both the native
functions of micropores and the enhanced diffusion capability
of reactants/products in mesopores are considered. Further
research of HSZs should include not only the new processes/
methodologies to realize the simultaneous and accurate
controlling over the compositions and structures on micro-
and mesoporous scales, catalytic performance such as activity,
product selectivity, coke formation and lifetime, but also a
general index to characterize and to correlate the structural
features and material performances of HSZs.
In addition to the further investigation on HSZs themselves,
the synthesis of HSZs-based composites will be another focus
in future. The loading of heterogeneous active species such as
metallic nanoparticles on zeolites, or the introduction of active
guests in the pore channels of conventional mesoporous silica,
has been proved to be effective in enhancing the material
performances of zeolites or conventional mesoporous materials.
One can expect that the loading of active species in the
hierarchical pore channels of HSZs should be equally effective
as in conventional mesoporous materials. Little work has
been reported in this direction but the results have been very
encouraging.77–80 Such a composite combines the advantages
of zeolite crystals of native catalytic activity, mesoporous
structures benefiting the fast diffusion of reactants/products,
and the additional functions of introduced guests and their
possible synergistic effect with the HSZs supports.
The authors thank the NSFC (No. 20633090, 20703055,
50872140) for financial support.
Notes and references
1 C. T. Kresge, M. E. Leonowicz, W. J. Roth, J. C. Vartuli andJ. S. Beck, Nature, 1992, 359, 710.
2 D. Y. Zhao, J. L. Feng, Q. S. Huo, N. Melosh, G. H. Fredrickson,B. F. Chmelka and G. D. Stucky, Science, 1998, 279, 548.
3 S. Bagshaw, E. Prouzet and T. Pinnavaia, Science, 1995, 269, 1242.4 Z. Zhang, Y. Han, L. Zhu, R. Wang, Y. Yu, S. Qiu, D. Zhao andF. Xiao, Angew. Chem., Int. Ed., 2001, 40, 1258.
5 Y. Liu, W. Zhang and T. Pinnavaia, Angew. Chem., Int. Ed., 2001,40, 1255.
6 H. Wang, Y. Liu and T. J. Pinnavaia, J. Phys. Chem. B, 2006,110, 4524.
7 A. Karlsson, M. Stocker and R. Schmidt,MicroporousMesoporousMater., 1999, 27, 181.
8 M. K. Choi, H. S. Cho, R. Srivastava, C. Venkatesan, D.-H. Chiand R. Ryoo, Nat. Mater., 2006, 5, 718.
9 H. Wang and T. J. Pinnavaia, Angew. Chem., Int. Ed., 2006,45, 7603.
10 F.-S. Xiao, L. Wang, C. Yin, K. Lin, Y. Di, J. Li, R. Xu, D. S. Su,R. Schlogl, T. Yokoi and T. Tatsumi, Angew. Chem., Int. Ed.,2006, 45, 3090.
11 J. Zhao, J. Zhou, Y. Chen, Q. He, M. Ruan, L. Guo, J. Shi andH. Chen, J. Mater. Chem., 2009, 19, 7614.
12 C. J. H. Jacobsen, C. Madsen, J. Houzvicka, I. Schmidt andA. Carlsson, J. Am. Chem. Soc., 2000, 122, 7116.
13 A. Sakthivel, S.-J. Huang, W.-H. Chen, Z.-H. Lan, K.-H. Chen,T.-W. Kim, R. Ryoo, A. S. T. Chiang and S.-B. Liu, Chem. Mater.,2004, 16, 3168.
14 H. Zhu, Z. Liu, Y. Wang, D. Kong, X. Yuan and Z. Xie, Chem.Mater., 2008, 20, 1134.
15 W. Fan, M. A. Snyder, S. Kumar, P.-S. Lee, W. C. Yoo,A. V. McCormick, R. L. Penn, A. Stein and M. Tsapatsis, Nat.Mater., 2008, 7, 984.
16 J. C. Groen, J. A. Moulijn and J. Perez-Ramırez, J. Mater. Chem.,2006, 16, 2121.
17 Y. Tao, H. Kanoh, L. Abrams and K. Kaneko, Chem. Rev., 2006,106, 896.
18 B. A. Williams, S. M. Babitz, J. T. Miller, R. Q. Snurr andH. H. Kung, Appl. Catal., A, 1999, 177, 161.
19 J. Cejka and S. Mintova, Catal. Rev., 2007, 49, 457.20 J. Perez-Ramırez, C. H. Christensen, K. Egeblad and J. C. Groen,
Chem. Soc. Rev., 2008, 37, 2530.21 X. Meng, F. Nawaz and F.-S. Xiao, Nano Today, 2009, 4, 292.22 R. Chal, C. Gerardin, M. Bulut and S. v. Donk, ChemCatChem,
2011, 3, 67.23 R. Srivastava, M. Choi and R. Ryoo, Chem. Commun., 2006,
4489.24 H. Xin, A. Koekkoek, Q. Yang, R. v. Santen, C. Li and
E. J. M. Hensen, Chem. Commun., 2009, 7590.25 K. Cho, H. S. Cho, L.-C. de Menorval and R. Ryoo, Chem.
Mater., 2009, 21, 5664.26 Y. Cheneviere, F. Chieux, V. Caps and A. Tuel, J. Catal., 2010,
269, 161.27 M. Choi, R. Srivastava and R. Ryoo, Chem. Commun., 2006, 4380.28 N. Danilina, F. Krumeich and J. A. v. Bokhoven, J. Catal., 2010,
272, 37.29 G. V. Shanbhag, M. Choi, J. Kim and R. Ryoo, J. Catal., 2009,
264, 88.30 J. Kim, M. Choi and R. Ryoo, J. Catal., 2010, 269, 219.31 V. N. Shetti, J. Kim, R. Srivastava, M. Choi and R. Ryoo,
J. Catal., 2008, 254, 296.32 M. Choi, K. Na, J. Kim, Y. Sakamoto, O. Terasaki and R. Ryoo,
Nature, 2009, 461, 246.33 K. Na, W. Park, Y. Seo and R. Ryoo, Chem. Mater., 2011,
23, 1273.34 K. Na, M. Choi, W. Park, Y. Sakamoto, O. Terasaki and R. Ryoo,
J. Am. Chem. Soc., 2010, 132, 4169.35 J. Schick, T. J. Daou, P. Caullet, J.-L. Paillaud, J. Patarina and
C. Mangold-Callarec, Chem. Commun., 2011, 47, 902.36 J. Song, L. Ren, C. Yin, Y. Ji, Z. Wu, J. Li and F.-S. Xiao, J. Phys.
Chem. C, 2008, 112, 8609.37 J. Hua and Y. Han, Chem. Mater., 2009, 21, 2344.38 L. Chen, S. Y. Zhu, Y. M. Wang and M.-Y. He, New J. Chem.,
2010, 34, 2328.39 Y. Fang, H. Hu and G. Chen, Chem. Mater., 2008, 20, 1670.40 H. Xin, J. Zhao, S. Xu, J. Li, W. Zhang, X. Guo, E. J. M. Hensen,
Q. Yang and C. Li, J. Phys. Chem. C, 2010, 114, 6553.41 P. Y. Chao, S. T. Tsai, T. C. Tsai, J. B. Mao and X. W. Guo, Top.
Catal., 2009, 52, 185.42 J. Zhao, Z. Hua, Z. Liu, Y. Li, L. Guo, W. Bu, X. Cui, M. Ruan,
H. Chen and J. Shi, Chem. Commun., 2009, 7578.
43 J. Zhou, Z. Hua, J. Shi, Q. He, L. Guo and M. Ruan, Chem.–Eur.J., 2009, 15, 12949.
44 J. Zhou, Z. Hua, J. Zhao, Z. Gao, S. Zeng and J. Shi, J. Mater.Chem., 2010, 20, 6764.
45 J. Zhou, Z. Hua, X. Cui, Z. Ye, F. Cui and J. Shi, Chem. Commun.,2010, 46, 4994.