Synthesis of SrTiO₃ nanoparticles by sonochemical method and their shape evolution process

Well-crystallized SrTiO₃ nanopowders including star-shaped, cubic and spherical were successfully synthesized by ultrasound irradiation under low temperature. The reactant concentrations, sonication time and pH value of the solution were investigated. Characterization techniques such as X-ray powder diffraction analysis, scanning electron microscopy and energy dispersive X-ray analysis were used to investigate the products. The results show that the SrTiO₃ shape evolution can be controlled by reactant concentration, sonication time and pH value. Star-shaped SrTiO₃ nanoparticles with four symmetric arms can be obtained by controlling at pH 12 and 13 when the reactant concentration is low. With the increase of the reactant concentration cubic and spherical nanoparticles are obtained. When the pH is 14, cubic and spherical SrTiO₃ nanoparticles can be synthesized.