New Intercalation Materials

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9422667 Whittingham Previous research by this investigator has established that new oxide intercalation hosts can be readily synthesized using hydrothermal techniques, and that changing the acidity or the cations present in the reaction medium dramatically determines the crystalline structure formed. By appropriate choice of reaction medium it is proposed to form new structures containing large tunnels or channels, similar to those found in aluminosilicate zeolites, that will offer unique properties for the materials chemistry. The feasibility of this approach has been demonstrated for tungsten and molybdenum oxides. Major emphasis in this project will be placed on vanadium and manganese oxides, and on a new titanium phosphate. Because enhanced diffusion in such materials are expected, the diffusion/ionic mobility will be determined. The host materials also will be characterized for their ability to be intercalated by a variety of guest ions and molecules, and their chemical and physical properties will be determined using x-ray, electrochemical, and electrical measurements and the standard analytical techniques. %%% Zeolitic microporous materials have frameworks containing mostly the redox inactive elements aluminum and silicon. From a chemical point of view it would be highly desirable to have a framework containing, or built from, redox active species such as transition metals. In addition, for many electrochemical applications it would be preferable to work with oxides rather than sulfides because of their greater ease of handling, lower cost and for energy storage their greater electrochemical potential. The goal of this project is to synthesize transition metal oxide materials with open structures, that might have some of the properties and applications of the aluminosilicate zeolitic materials, have novel applications and be potentially electrochemically active.