Synthesis of Highly Tetragonal BaTiO3 Nanopowders Using Acetone as a Solvent by Alkoxide-Hydroxide Route

Abstract

BaTiO3 (BT) nanopowders were synthesized in acetone to remove the TiO2 second phase, which was formed in the specimens synthesized in the 2-methoxyethanol solvent at above 100 degrees C due to H2O evaporation. No TiO2 second phase was formed in the specimens synthesized in acetone, even at 260 degrees C, due to the low boiling temperature of acetone which evaporated at above 55 degrees C and suppressed the H2O evaporation by increasing the vapor pressure in the vessel. However, for the BT nanopowders synthesized at 250 degrees C for 60 h, TiO2 second phase was formed at a Ba/Ti ratio of <= 1.5 and the BT nanopowders were agglomerated at a ratio of >= 3.0. Homogeneous BT nanopowders were obtained at a ratio of 2.0 and they exhibited a high c/a ratio of 1.0082 with a small size of 95.2 nm. Therefore, these nanopowders can be a good candidate for future multilayer ceramic capacitor. (C) 2011 The Japan Society of Applied Physics