Microwave Decomposition of Metal Alkoxides to Nanoporous Metal Oxides - A Mechanistic Study

摘要

Synthesis of nanoscaled TiO_2 and ZrO_2 by pyrolysis of metal alcoholate - paraffin emulsions using microwave heating (Colloidal Microwave Pyrolysis, CMP) as well as conventional heating (Colloidal Conventional Pyrolysis, CCP) is described. The ceramic yield of the inorganic products, the pore structure, grain size and phase composition of the nanoscaled oxides is influenced to a lesser extend by the heating method as by the organic by-products. Different reaction paths are found for Ti-alcoholate as compared to Zr-alcoholate. A mechanism is proposed for the decomposition of each alcoholate, showing that microwave heating enhances the catalytic activity of the oxide powders generated during the reaction.