Intercalation Chemistry

Intercalation Chemistry introduces the specialist reader to the breadth of intercalation chemistry and the newcomer to the diverse research opportunities and challenges available in synthetic and reaction chemistry and also in the controlled modification of physical properties. Topics covered range from graphite chemistry to sheet silicate intercalates, diffusion and shape-selective catalysis in zeolites, organic and organometallic intercalation compounds of the transition metal dichalcogenides, and solvated intercalation compounds of layered chalcogenide and oxide bronzes. This book is comprised of 18 chapters and begins with an introduction to intercalation chemistry. The discussions that follow focus on the intercalation chemistry of graphite and of complex oxides with both two (clays and acid phosphates)- and three (zeolites)-dimensional structures, along with organic conversions that have been discovered using essentially smectite (i.e., montmorillonite- and hectorite-based) intercalates. The next chapters focus on ß-aluminas, acid salts of tetravalent metals with layered structure, and layered chalcogenides and halides with simple and hydrated cations as well as organic and organometallic ions. The book also considers the chemistry, thermodynamics, and applications of intermetallic compounds that incorporate hydrogen, intercalation in the context of biological systems, crystallographic shear structures, and intercalation reactions of oxides and chalcogenides of vanadium, molybdenum, and tungsten. The final chapter touches on the physical properties of some intercalation compounds of the dichalcogenides. This book is intended for researchers in the various materials science disciplines.

Conjugated polymers suoh as polyaoetylene (CH)x polyphenylene (C6H4)x' poly thiophene (C4H2S)x' etc., which are insulators in their pristine state, can be brought to the metallic state after "doping" with ohemioal speoies whioh oan be either eleotron donors or I aoceptors. . This doping prooess involves a oharge transfer between the dopant moleoule and the polymer ohain whioh are then supposed to be spatially olose to each other. It follows that the meohanism of doping must be oonsidered as an aotual interoalation process, which will greatly affeot the struotural oharacteristios of the starting material, as well as its morphology, as has been observed during the 2 intercalation of graphite and layered compounds . In parallel with these modifioations, the band struoture of the system changes yielding a new set of eleotronio properties. It is evident therefore that the struotural and eleotronio properties are intimately related, and must be studied simultaneously in the same system to give reliable information. A great number of studies have been devoted to the structural and electronic properties of conjugated polymers after a chemical or 2 electrochemical doping process . Most of these concern the properties of the system for a given dopant concentration. With this approach a universal pioture of the polymer/dopant system is very diffioult to obtain, as a comparison between different experiments is very hazardous. On the other hand, only a small number of measurements have been performed during the continuous electroohemioal doping of various polymers.

This volume provides a record of the second ASI on the subject "Chemical Physics of Intercalation", which was patterned after its highly successful July 1987 predecessor. A growing community of chemists, physicists and materials scientists has come to appreciate the utility of extending the intercalation concept to generic guest-host compounds and solid solutions. The unifying themes are the complex phase equilibria which result from the competition between repulsive and attractive interactions between and within the guest and host substructures, the tunability of properties by control of guest concentration and superlattice periodicity, and the broad spectrum of potential applications which these materials may provide. The success of this initiative may be judged by noting the enlarged scope of materials covered in this volume as compared to its predecessor. The present volume covers the spectrum from 3-dimensional oxides, 2-dimensional classical layer intercalates,- dimensional doped polymers and zero-dimensional doped fullerene lattices. Hybrid systems such as polymers in layer hosts and nonporous hosts are also treated. Several chapters provide global unifying viewpoints by focussing on sold state chemical aspects, transport and optical properties, the occurrence of superconductivity, etc.

Materials with layered structures remain an extensively investigated subject in current physics and chemistry. Most of the promising technological applications however deal with intercalation compounds of layered materials. Graphite intercalation compounds have now been known for a long time. Intercalation in transition metal dichalcogenides, on the other hand, has been investigated only recently. The amount of information on intercalated layered materials has increased far beyond the original concept for this volume in the series Physics and Chemistry of Materials with Layered Structures. The large size of this volume also indicates how important this field of research will be, not only in basic science, but also in industrial and energy applications. In this volume, two classes of materials are included, generally investigated by different scientists. Graphite intercalates and intercalates of other inorganic com pounds actually constitute separate classes of materials. However, the similarity between the intercalation techniques and some intercalation processes does not justify this separation, and accounts for the inclusion of both classes in this volume. The first part of the volume deals with intercalation processes and intercalates of transition metal dichalcogenides. Several chapters include connected topics necessary to give a good introduction or comprehensive review of these types of materials. Organic as well as inorganic intercalation compounds are treated. The second part includes contributions concerning graphite intercalates. It should be noted that graphite intercalation compounds have already been mentioned in Volumes I and V.

The combination of solid materials of different structural dimensionality with atomic or molecular guest species via intercalation processes represents a unique and widely variable low temperature synthesis strategy for the design of solids with particular composition, structure and physical properties. In the last decade this field has experienced a rapid development and represents now an established specific domain of solid state research and materials science. Substantial progress has been made with respect to an understanding of the complex relationship between structure, bonding, physical properties and chemical reactivity since the first volume on the subject appeared in this series in 1979 (Intercalated Layered Materials, F. Levy, ed.). The purpose of this volume is to present a survey on progress and per spectives based on the treatment of a series of major areas of activities in this field. By the very nature of its subject this monograph has an interdisciplinary character and addresses itself to chemists, physicists and materials scien tists interested in intercalation research and related aspects such as design and characterization of complex materials, low temperature synthesis, solid state reaction mechanisms, electronic/ionic conductivity, control of electronic properties of solids with different structural dimensionality and application of intercalation systems. Several chapters have been devoted to specific groups of host lattices.

For the first time the discipline of modern inorganic chemistry has been systematized according to a plan constructed by a council of editorial advisors and consultants, among them three Nobel laureates (E.O. Fischer, H. Taube and G. Wilkinson). Rather than producing a collection of unrelated review articles, the series creates a framework which reflects the creative potential of this scientific discipline. Thus, it stimulates future development by identifying areas which are fruitful for further research. The work is indexed in a unique way by a structured system which maximizes its usefulness to the reader. It augments the organization of the work by providing additional routes of access for specific compounds, reactions and other topics.

This volume is prepared from lecture notes for the course "Intercalation in Layered Materials" which was held at the Ettore Majorana Centre for Scientific Culture at Erice, Sicily in July, 1986, as part of the International School of Materials Science and Tech nology. The course itself consisted of formal tutorial lectures, workshops, and informal discussions. Lecture notes were prepared for the formal lectures, and short summaries of many of the workshop presentations were prepared. This volume is based on these lecture notes and research summaries. The material is addressed to advanced graduate students and postdoctoral researchers and assumes a background in basic solid state physics. The goals of this volume on Intercalation in Layered Materials include an introduc tion to the field for potential new participants, an in-depth and broad exposure for stu dents and young investigators already working in the field, a basis for cross-fertilization between workers on various layered host materials and with various intercalants, and an elaboration of the complementarity of intercalated layered materials with deliberately structured superlattices.