Unusual approaches to the preparation of heterogeneous catalysts and supports using water in subcritical and supercritical states

The prospective ways of using water in sub- and supercritical states for the preparation of nanocrystal oxide catalysts Ce0.5Zr0.5O2, Ce0.1YxZr0.9-O-x(2), Zr1-xYxO2, Zr1-xInxO2, La2CuO4, supported catalysts Pd/Rh/ZrO2 and Pd/Rh/TiO2, and supports CeO2, ZrO2, TiO2 are discussed. The proposed technique is characterized by high productivity. It is also ecologically friendly and enables one to obtain multicomponent oxide catalysts with chemical and phase composition and properties that can be changed within large ranges. The physicochemical properties of sub- and supercritical water are discussed. A brief review of the present studies on the use of critical media in various physicochemical processes is given.