Solvothermal synthesis of SrTiO3 nanoparticles precisely controlled in surface crystal planes and their photocatalytic activity

Abstract Strontium titanate (SrTiO3) nanoparticles of cubes, spheres, and flake-type morphology were obtained by a solvothermal synthesis in H2O/polyols mixed solution. Size of cubic particles bounded by {1 0 0} faces was controlled in the range from 24 to 43 nm by the adjustment of initial volume ratio in H2O/diethylene glycol. Cubic particles exhibited high decomposition activity of organic compounds under ultraviolet irradiation. On the other hand, flake-type particles bounded mainly by {1 1 0} faces were obtained in H2O/ethylene glycol solution system, highly active for H2 evolution in photocatalytic reaction. These results indicate that the {1 0 0} surface shows high oxidative activity and that the {1 1 0} surface shows high reductive activity.