NANOPARTICLES OF ANATASE BY ELECTROSTATIC SPRAYING OF AN ALKOXIDE SOLUTION

Much effort has been directed toward the synthesis of submicron particles with a narrow size distribution for the preparation of nanophase ceramic materials1-3that have improved properties.4This is done by consolidating and sintering nanometer-sized particles, often called nanoparticles.5In most cases, the nanoparticles are synthesized in vacuum or at low pressure by evaporation of a bulk source material. Synthesis of nanocomposite materials in solution is limited by aggregation; although additives help keep particles dispersed in solution, they have to be removed before a pure, nanophase solid can be formed.6Because condensation reactions are enhanced during the drying stage of the sol-gel process, particles of gel-forming compounds become larger than those produced by gasphase methods.7Titania particles have been made from metal-organic compounds by reactions in aerosols.8, 9Particles smaller than 100 nm were made by thermal decomposition of titanium alkoxides.10These methods, however, can be applied only to volatile compounds. © 1992, American Chemical Society. All rights reserved.