ABSTRACT Metal alkoxides, many of which can easily be prepared and purified by distillation, can act as convenient precursors for preparing metal oxides in a high surface area form. The preparation method involves controlled hydrolysis of the parent alkoxide, usually in an alcoholic solution, followed by drying the resulting alcogel and calcining at a relatively low temperature. When mixed metal oxides, such as perovskites or spinels, are sought heterometallic alkoides can be used, or a solution of single alkoxides containing the desired metals. Mixing at the molecular level results in formation of multicomponent metal oxides at a temperature significantly lower than that needed for conventional ceramic processes; this mitigates sintering and facilitates access to high surface area materials. After a brief introduction to the chemistry of the alkoxide sol-gel method, the field is reviewed, with an emphasis on recent literature reporting on the preparation of high-surface-area metal oxides having the perovskite and spinel structure types. For the case of spinels, the preparation of materials having a surface area above 200 m2g-1 has recently been reported. These materials have potential application in technological fields related to surface phenomena, such as heterogeneous catalysis or gas sensing.
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