Metal carbides hydrothermal synthesis

Such reactions are discussed at appropriate points throughout the book as each individual compound is being considered. A particularly important set of reactions in this category is the synthesis of element hydrides by hydrolysis of certain sulfides (to give H2S), nitrides (to give NH3), phosphides (PH3), carbides (C Hm), borides (B Hm), etc. Useful reviews are available on hydrometallurgy (the recovery of metals by use of aqueous solutions at relatively low temperatures), hydrothermal syntheses and the use of supercritical water as a reaction medium for chemistry. 

Other synthesis methods have also been developed but may not be practiced on a large commercial scale as compared to those indicated above. Examples of syntheses that begin from liquid phase precursors include the sol-gel, hydrothermal, and Pechini methods. In the course of these reaction schemes, polycondensation or precipitation occurs, and the volatile components are removed, often by thermal methods. Other synthesis routes to ceramic materials include the nitridation of metals to form metal nitrides and the carbothermal reduction of oxides to form carbides and borides. 

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. 

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