Preparation, Processing, and Characterization of Nano‐Crystalline BaTiO ₃ Powders and Ceramics Derived from Microemulsion‐Mediated Synthesis

Abstract

Monodisperse and nanocrystalline BaTiO 3 powders of different stoichiometries were synthesized through the hydrolytic decomposition of mixed metal alkoxide solutions with water‐in‐oil microemulsions as reaction media. The method allows a tailor‐made preparation of powder particles as small as 10 nm in average. Characterization with respect to purity, morphology, and behavior upon annealing was conducted in order to determine appropriate processing conditions for the preparation of pure, dense nanocrystalline ceramics. As a result, ceramics with a mean grain size as small as 35 nm were achieved. Raman spectroscopy revealed for the first time local tetragonality in pure nanocrystalline bulk BaTiO 3 ‐ceramics with such a fine microstructure.