Hydrothermal Synthesis of <scp> <scp>BaTiO</scp> </scp> ₃ Nanopowders Using <scp> <scp>TiO</scp> </scp> ₂ Nanoparticles

Abstract

Anatase TiO 2 nanoparticles, obtained by hydrolyzing titanium isopropoxide in distilled water, were used to synthesize BaTiO 3 ( BT ) nanopowder by the hydrothermal method. When titanium isopropoxide was used, BT nanopowder with a low tetragonality of 1.0070 was formed because of the presence of OH − ions in the oxygen sites and Ba vacancies. However, by changing the titanium source from titanium isopropoxide to TiO 2 nanoparticles, a homogeneous BT nanopowder with similar particle size and a high tetragonality of 1.0081 was synthesized. The size of the BT nanopowder particles was decreased by reducing the synthesis time. In particular, the BT nanopowder that was synthesized at 220°C for 16 h with a Ba / Ti molar ratio of 4.0 exhibited a high tetragonality of 1.0083 and a small particle size of 126.0 nm.