Synthesis of Inorganic Solids

Supercritical fluids (SCFs) are fascinating media for the synthesis of inorganic compounds [1]. This is due in part to the tremendous versatility of these fluids, especially in providing access to unusual and kinetically stabilized solid phases. It should not be assumed, however, that either the techniques or the concepts are particularly new. In fact, most of the current techniques are really just derivatives of the methods developed in the last 50-100 years. There is broadening of interest in this field as inorganic chemists continue to search for new synthetic routes to unusual compounds. Several outstanding earlier reviews summarized the field to date and inspired new workers to enter the field [2-4]. However the most recent of these reviews is now over 12 years old and substantial new results justify a more current review. 

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All issues about the preparation of inorganic solid catalysts that we have discussed above apply for the rapid sequential synthesis of inorganic solids by automated methodologies. As for HTE - and combinatorial approaches in organic chemistry, technical solutions for compound synthesis can be obtained commercially for a number of synthetic problems [42-45] and it is beyond the scope of this chapter to discuss all the technical details. 

It should also be mentioned here that a number of publications deal with the true parallel synthesis of inorganic solids by sputtering and chemical vapor deposition however, these approaches are of major use for other fields in materials science than for catalysis. For a broad overview of synthetic and screening efforts refer to [49],... 

SYNTHESIS OF INORGANIC SOLIDS 3.3.1 Solid-State Reaction Method... 

Common reactions encountered in the synthesis of inorganic solids... 

Various types of chemical reactions have been used for the synthesis of solid materials. Corbett [3] has written an excellent article on the subject. Some of the common reactions employed for the synthesis of inorganic solids are listed below ... 

Lin, 1.1., and Nadiv, S., Review of the phase transformation and synthesis of inorganic solids obtained by mechanical treatment (mechanochemical reactions),... 

Lin, I. J. Nadiv, S. (1979). Review of the Phase Transformation and Synthesis of Inorganic Solids Obtained by Mechanical Treatment (Mechanochemical Reactions). Materials Science and Engineering, Vol.39, No.2, pp. 193-209. 

As it can be seen from Table 24.3, processing of inorganic material using SAS and related processes is dominantly applied to obtain organic compounds which serve as precursors for the synthesis of inorganic solids. An interesting route to synthesize ceramic material was proposed... 

Molecular compounds are precursors in the synthesis of inorganic solids, e.g., in gas-phase synthesis of coatings. 

In die sections that follow, we briefly discuss the synthesis of inorganic solids by various methods with several examples, paying attention to the chemical routes. While oxide materials occupy a great part of the monograph, other classes of materials such as chalcogenides, carbides, fluorides and nitrides are also discussed. Superconducting oxides, intermetallics, porous materials and intergrowlh structures have been discussed in separate sections. We have added a new section on nanomaterials. 

In this book, we briefly examine the different types of reactions and methods employed in the synthesis of inorganic solid materials. Besides the traditional ceramic procedures, we discuss precursor methods, combustion method, topochemical reactions, intercalation reactions, ion-exchange reactions, alkali-flux method, sol-gel method, mechanochemical synthesis, microwave synthesis, electrochemical methods, pyrosol process, arc and skull methods and high-pressure methods. Hydrothermal and solvothermal syntheses are discussed separately and also in sections dealing with specific materials. Superconducting cuprates and intergrowth structures are discussed in separate sections. Synthesis of nanomaterials is dealt with in some detail. Synthetic methods for metal borides, carbides, nitrides, fluorides, sili-cides, phosphides and chalcogenides are also outlined. 

K.J., Vaidhyanathan, B., Ganguli, M., and Ramakrishnan, P.A. (1999) Synthesis of inorganic solids using microwaves. 

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