Low-temperature synthesis of strontium titanate particles with high specific surface area

Abstract

Strontium titanate (SrTiO₃) particles are expected to be applied to various catalysts, and many kinds of synthesis procedures of SrTiO₃ particles with a high specific surface area have been proposed. This study investigates a synthesis procedure of preparing SrTiO₃ particles with a high specific surface area by minimizing the crystallization temperature to the least possible value. The SrTiO₃ particles are prepared by maintaining spherical hydrous titania particles with smooth or porous surfaces in highly concentrated strontium hydroxide solutions at ≤120 °C. When porous hydrous titania particles are used as the raw material and the Sr/Ti ratio in the reaction solution is set at 10, spherical protrusions of SrTiO₃ develop on the surface of the original hydrous titania, even at a low temperature (25 °C). Single-phase SrTiO₃ particles with spherical protrusions composed of very fine crystallites are obtained by treatment at 40 °C for 24 h. These particles have a high BET specific surface area of 237 m² g⁻¹. The process developed herein is eco-friendly and effective for fabricating various perovskite-type compounds with a high specific surface area.