Peidong yang the chemistry of nanostructured materials

T heChemi s t r yof Nanos t r uct ur edMat er i al s Edi t or Pei dongYang Uni ver s i t yofCal i f or ni a,Ber kel ey,US A Published by World Scientific Publishing Co Pte Ltd Toh Tuck Link, Singapore 596224 USA office: Suite 202, 1060 Main Street, River Edge, NJ 07661 UK office: 57 Shelton Street, Covent Garden, London WC2H 9HE British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library THE CHEMISTRY OF NANOSTRUCTURED MATERIALS Copyright © 2003 by World Scientific Publishing Co Pte Ltd All rights reserved This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical, including photocopying, recording or any information storage and retrieval system now known or to be invented, without written permission from the Publisher For photocopying of material in this volume, please pay a copying fee through the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923, USA In this case permission to photocopy is not required from the publisher ISBN 981-238-405-7 ISBN 981-238-565-7 (pbk) Printed in Singapore FOREWORD Nanostructured material has been a very exciting research topic in the past two decades The impact of these researches to both fundamental science and potential industrial application has been tremendous and is still growing There are many exciting examples of nanostructured materials in the past decades including colloidal nanocrystal, bucky ball C60, carbon nanotube, semiconductor nanowire, and porous material The field is quickly evolving and is now intricately interfacing with many different scientific disciplines, from chemistry to physics, to materials science, engineer and to biology The research topics have been extremely diverse The papers in the literature on related subjects have been overwhelming and is still increasing significantly each year The research on nanostructured materials is highly interdisciplinary because of different synthetic methodologies involved, as well as many different physical characterization techniques used The success of the nanostructured material research is increasingly relying upon the collective efforts from various disciplines Despite the fact that the practitioners in the field are coming from all different scientific disciplines, the fundamental of this increasing important research theme is unarguably about how to make such nanostructured materials For this reason, chemists are playing a significant role since the synthesis of nanostructured materials is certainly about how to assemble atoms or molecules into nanostructures of desired coordination environment, sizes, and shapes A notable trend is that many physicists and engineers are also moving towards such molecular based synthetic routes The exploding information in this general area of nanostructured materials also made it very difficult for newcomers to get a quick and precise grasp of the status of the field itself This is particularly true for graduate students and undergraduates who have interest to research in the area The purpose of this book is to serve as a step-stone for people who want to get a glimpse of the field, particularly for the graduate students and undergraduate students in chemistry major Physics and engineering researchers would also find this book useful since it provides an interesting collection of novel nanostructured materials, both in terms of their preparative methodologies and their structural and physical property characterization The book includes thirteen authoritative accounts written by experts in the field The materials covered here include porous materials, carbon nanotubes, coordination networks, semiconductor nanowires, nanocrystals, Inorganic Fullerene, block copolymer, interfaces, catalysis and nanocomposites Many of these materials represent the most exciting, and cutting edge research in the recent years v vi Foreword While we have been able to cover some of these key areas, the coverage of book is certainly far from comprehensive as this wide-ranging subject deserves Nevertheless, we hope the readers will find this an interesting and useful book Feb 2003 Peidong Yang Berkeley, California CONTENTS Foreword v Crystalline Microporous and Open Framework Materials Xianhui Bu and Pingyun Feng Mesoporous Materials Abdelhamid Sayari 39 Macroporous Materials Containing Three-Dimensionally Periodic Structures Younan Xia, Yu Lu, Kaori Kamata, Byron Gates and Yadong Yin 69 CVD Synthesis of Single-Walled Carbon Nanotubes Bo Zheng and Jie Liu 101 Nanocrystals M P Pileni 127 Inorganic Fullerene-Like Structures and Inorganic Nanotubes from 2-D Layered Compounds R Tenne Semiconductor Nanowires: Functional Building Blocks for Nanotechnology Haoquan Yan and Peidong Yang Harnessing Synthetic Versatility Toward Intelligent Interfacial Design: Organic Functionalization of Nanostructured Silicon Surfaces Lon A Porter and Jillian M Buriak 147 183 227 Molecular Networks as Novel Materials Wenbin Lin and Helen L Ngo 261 Molecular Cluster Magnets Jeffrey R Long 291 Block Copolymers in Nanotechnology Nitash P Balsara and Hyeok Hahn 317 vii  viii Contents The Expanding World of Nanoparticle and Nanoporous Catalysts Robert Raja and John Meurig Thomas 329 Nanocomposites Walter Caseri 359 CRYSTALLINE MICROPOROUS AND OPEN FRAMEWORK MATERIALS XIANHUI BU Chemistry Department, University of California, CA93106, USA PINGYUN FENG Chemistry Department, University of California, Riverside, CA92521, USA A variety of crystalline microporous and open framework materials have been synthesized and characterized over the past 50 years Currently, microporous materials find applications primarily as shape or size selective adsorbents, ion exchangers, and catalysts The recent progress in the synthesis of new crystalline microporous materials with novel compositional and topological characteristics promises new and advanced applications The development of crystalline microporous materials started with the preparation of synthetic aluminosilicate zeolites in late 1940s and in the past two decades has been extended to include a variety of other compositions such as phosphates, chalcogenides, and metal-organic frameworks In addition to such compositional diversity, synthetic efforts have also been directed towards the control of topological features such as pore size and channel dimensionality In particular, the expansion of the pore size beyond 10Å has been one of the most important goals in the pursuit of new crystalline microporous materials Introduction Microporous materials are porous solids with pore size below 20Å [1,2,3,4] Porous solids with pore size between 20 and 500Å are called mesoporous materials Macroporous materials are solids with pore size larger than 500Å Mesoporous and macroporous materials have undergone rapid development in the past decade and they are covered in other chapters of this book A frequently used term in the field of microporous materials is “molecular sieves” [5] that refers to a class of porous materials that can distinguish molecules on the basis of size and shape This chapter focuses on crystalline microporous materials with a three-dimensional framework and will not discuss amorphous microporous materials such as carbon molecular sieves However, it should be kept in mind that some amorphous microporous materials can also display shape or size selectivity and have important industrial applications such as air separation [6] The development of crystalline microporous materials started in late 1940s with the synthesis of synthetic zeolites by Barrer, Milton, Breck and their coworkers [7,8] Some commercially important microporous materials such as zeolites A, X, and Y were made in the first several years of Milton and Breck’s work In the following thirty years, zeolites with various topologies and chemical compositions (e.g., Si/Al ratios) were prepared, culminating with the synthesis of ZSM-5 [9] and X.-H Bu and P.-Y Feng aluminum-free pure silica polymorph silicalite [10] in 1970s A breakthrough leading to an extension of crystalline microporous materials to non-aluminosilicates occurred in 1982 when Flanigen et al reported the synthesis of aluminophosphate molecular sieves [11,12] This breakthrough was followed by the development of substituted aluminophosphates Since late 1980s and the early 1990s, crystalline microporous materials have been made in many other compositions including chalcogenides and metal-organic frameworks [13,14] Crystalline microporous materials usually consist of a rigid three-dimensional framework with hydrated inorganic cations or organic molecules located in the cages or cavities of the inorganic or hybrid inorganic-organic host framework Organic guest molecules can be protonated amines, quaternary ammonium cations, or neutral solvent molecules Dehydration (or desolvation) and calcination of organic molecules are two methods frequently used to remove extra-framework species and generate microporosity Crystalline microporous materials generally have a narrow pore size distribution This makes it possible for a microporous material to selectively allow some molecules to enter its pores and reject some other molecules that are either too large or have a shape that does not match with the shape of the pore A number of applications involving microporous materials utilize such size and shape selectivity Figure Nitrogen adsorption and desorption isotherms typical of a microporous material Data were measured at 77K on a Micromeritics ASAP 2010 Micropore Analyzer for Molecular Sieve 13X The structure of 13X is shown in Fig The sample was supplied by Micromeritics Two important properties of microporous materials are ion exchange and gas sorption The ion exchange is the exchange of ions held in the cavity of microporous materials with ions in the external solutions The gas sorption is the ability of a Crystalline Microporous and Open Framework Materials microporous material to reversibly take in molecules into its void volume (Fig 1) For a material to be called microporous, it is generally necessary to demonstrate the gas sorption property The report by Davis et al of a hydrated aluminophosphate VPI-5 with pore size larger than 10Å in 1988 generated great enthusiasm toward the synthesis of extralarge pore materials [15] The expansion of the pore size is an important goal of the current research on microporous materials [16] Even though microporous materials include those with pore sizes between 10 to 20Å, The vast majority of known crystalline microporous materials have a pore size