Hierarchical nanofabrication of microporous crystals with ordered mesoporosity.

Shaped zeolite nanocrystals and larger zeolite particles with three-dimensionally ordered mesoporous (3DOm) features hold exciting technological implications for manufacturing thin, oriented molecular sieve films and realizing new selective, molecularly accessible and robust catalysts. A recognized means for controlled synthesis of such nanoparticulate and imprinted materials revolves around templating approaches, yet identification of an appropriately versatile template has remained elusive. Because of their highly interconnected pore space, ordered mesoporous carbon replicas serve as conceptually attractive materials for carrying out confined synthesis of zeolite crystals. Here, we demonstrate how a wide range of crystal morphologies can be realized through such confined growth within 3DOm carbon, synthesized by replication of colloidal crystals composed of size-tunable (about 10-40 nm) silica nanoparticles. Confined crystal growth within these templates leads to size-tunable, uniformly shaped silicalite-1 nanocrystals as well as 3DOm-imprinted single-crystal zeolite particles. In addition, novel crystal morphologies, consisting of faceted crystal outgrowths from primary crystalline particles have been discovered, providing new insight into constricted crystal growth mechanisms underlying confined synthesis.

[1]  S. Mintova,et al.  Mechanism of the transformation of silica precursor solutions into Si-MFI zeolite. , 2002, Angewandte Chemie.

[2]  M. Ogura,et al.  Alkali-treatment technique — new method for modification of structural and acid-catalytic properties of ZSM-5 zeolites , 2001 .

[3]  Rajendra Srivastava,et al.  Amphiphilic organosilane-directed synthesis of crystalline zeolite with tunable mesoporosity , 2006, Nature materials.

[4]  H. Kanoh,et al.  ZSM-5 monolith of uniform mesoporous channels. , 2003, Journal of the American Chemical Society.

[5]  C. Jacobsen,et al.  Confined space synthesis. A novel route to nanosized zeolites. , 2000, Inorganic chemistry.

[6]  Timothy O. Drews,et al.  Mechanistic principles of nanoparticle evolution to zeolite crystals , 2006, Nature materials.

[7]  D. Shantz,et al.  Anionic microemulsion-mediated low temperature synthesis of anisotropic silicalite-1 nanocrystals. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[8]  Mark E. Davis,et al.  Issues in the synthesis of crystalline molecular sieves: towards the crystallization of low framework-density structures. , 2004, Chemphyschem : a European journal of chemical physics and physical chemistry.

[9]  Otto Glatter,et al.  The interpretation of real-space information from small-angle scattering experiments , 1979 .

[10]  D. Vlachos,et al.  Spontaneous Formation of Silica Nanoparticles in Basic Solutions of Small Tetraalkylammonium Cations , 2004 .

[11]  Lesile Glasser.  The chemistry of silica: By Ralph K. Iller. Pp. vii+ 866. Wiley, Chichester. 1979, £39.50 , 1980 .

[12]  M. Ogura,et al.  Formation of uniform mesopores in ZSM-5 zeolite through treatment in alkaline solution , 2000 .

[13]  M. Snyder,et al.  Hierarchical nanomanufacturing: from shaped zeolite nanoparticles to high-performance separation membranes. , 2007, Angewandte Chemie.

[14]  W. Stöber,et al.  Controlled growth of monodisperse silica spheres in the micron size range , 1968 .

[15]  Astrid Boisen,et al.  Carbon Nanotube Templated Growth of Mesoporous Zeolite Single Crystals , 2001 .

[16]  V. Valtchev,et al.  Mechanism of zeolite A nanocrystal growth from colloids at room temperature. , 1999, Science.

[17]  Yushan Yan,et al.  Control of size and yield of pure-silica-zeolite MFI nanocrystals by addition of methylene blue to the synthesis solution , 2007 .

[18]  B. Schoeman.  Analysis of the nucleation and growth of TPA-silicalite-1 at elevated temperatures with the emphasis on colloidal stability , 1998 .

[19]  Toshiyuki Yokoi,et al.  Periodic arrangement of silica nanospheres assisted by amino acids. , 2006, Journal of the American Chemical Society.

[20]  Yousheng Tao,et al.  Mesopore-modified zeolites: preparation, characterization, and applications. , 2006, Chemical reviews.

[21]  R. A. Santen,et al.  Combined in situ 29Si NMR and small-angle X-ray scattering study of precursors in MFI zeolite formation from silicic acid in TPAOH solutions , 2003 .

[22]  B. Schoeman,et al.  A study of the initial stage in the crystallization of TPA-silicalite-1 , 1996 .

[23]  O. Terasaki,et al.  Microstructural Optimization of a Zeolite Membrane for Organic Vapor Separation , 2003, Science.

[24]  C. Jacobsen,et al.  Zeolites by confined space synthesis – characterization of the acid sites in nanosized ZSM-5 by ammonia desorption and 27Al/29Si-MAS NMR spectroscopy , 2000 .

[25]  L. Scriven,et al.  Silica nanoparticle crystals and ordered coatings using lys-sil and a novel coating device. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[26]  K. B. Yoon.  Organization of zeolite microcrystals for production of functional materials. , 2007, Accounts of chemical research.

[27]  H. Kanoh,et al.  Mesopore-Modified Zeolites: Preparation, Characterization, and Applications , 2006 .

[28]  Jinxiang Dong,et al.  A novel method for the preparation of zeolite ZSM-5 , 1990 .

[29]  H. Giesche.  Synthesis of monodispersed silica powders II. Controlled growth reaction and continuous production process , 1994 .

[30]  C. Jacobsen,et al.  Nanosized zeolite crystals—convenient control of crystal size distribution by confined space synthesis , 1999 .

[31]  D. Vlachos,et al.  Structure of the silica phase extracted from silica/(TPA)OH solutions containing nanoparticles , 2003 .

[32]  W. Bras,et al.  Homogeneous versus Heterogeneous Zeolite Nucleation , 1995 .

[33]  Michael Tsapatsis,et al.  Nanoparticles in Lysine−Silica Sols , 2006 .

[34]  M. Ogura.  Towards Realization of a Micro- and Mesoporous Composite Silicate Catalyst , 2008 .

[35]  M. Coppens,et al.  Facile synthesis of ZSM-5 composites with hierarchical porosity , 2008 .

[36]  B. Binks.  Modern characterization methods of surfactant systems , 1999 .

[37]  J. Pople,et al.  Study on Synthesis of TPA-Silicalite-1 from Initially Clear Solutions of Various Base Concentrations by in Situ Calorimetry, Potentiometry, and SAXS , 2004 .

[38]  R. Dessau,et al.  Aluminum zoning in ZSM-5 as revealed by selective silica removal , 1992 .

[39]  T. Pinnavaia,et al.  Colloid-Imprinted Carbons as Templates for the Nanocasting Synthesis of Mesoporous ZSM-5 Zeolite , 2003 .

[40]  Vladimiros Nikolakis,et al.  Zeolite Growth by Addition of Subcolloidal Particles: Modeling and Experimental Validation , 2000 .

[41]  Woo-Sik Kim,et al.  Preparation of large monodispersed spherical silica particles using seed particle growth. , 2005, Journal of colloid and interface science.

[42]  R. Ryoo,et al.  Mesoporous materials with zeolite framework: remarkable effect of the hierarchical structure for retardation of catalyst deactivation. , 2006, Chemical communications.

[43]  R. Prins,et al.  Friedel-Crafts alkylations over hierarchical zeolite catalysts , 2008 .

[44]  A. Koster,et al.  Exploratory study of mesopore templating with carbon during zeolite synthesis , 2003 .

[45]  Michael Tsapatsis,et al.  Hierarchical Nanomanufacturing: From Shaped Zeolite Nanoparticles to High-Performance Separation Membranes , 2007 .

[46]  J. Moulijn,et al.  Optimal Aluminum‐Assisted Mesoporosity Development in MFI Zeolites by Desilication. , 2004 .

[47]  G. Salama,et al.  Merocyanine 540 as an optical probe of transmembrane electrical activity in the heart , 1976, Science.

[48]  Yunming Fang,et al.  An ordered mesoporous aluminosilicate with completely crystalline zeolite wall structure. , 2006, Journal of the American Chemical Society.

[49]  M. Ogura,et al.  Formation of ZMM-n: The composite materials having both natures of zeolites and mesoporous silica materials , 2007 .

[50]  O. Glatter,et al.  A new method for the evaluation of small‐angle scattering data , 1977 .

[51]  Andreas Stein,et al.  Dual Templating of Macroporous Silicates with Zeolitic Microporous Frameworks , 1999 .

[52]  C. Jacobsen,et al.  Mesoporous Zeolite Single Crystals. , 2000 .