Solvothermal synthesis of strontium titanate nanocrystallines from metatitanic acid and photocatalytic activities

Herein, directly using cheap industrial intermediate, metatitanic acid, as a starting material, strontium titanate nanocrystallines have been synthesized successfully by a simple solvothermal method. The crystal growth of SrTiO3 nanocrystallines was very sensitive to the volume ratio of alcohol (EtOH) to water. Only when products were prepared with the solvent including water, perovskite SrTiO3 nanocrystallines could be obtained. SrTiO3 nanocrystallines prepared with the volume ratio of EtOH to water of 1:1 have relatively small and uniform crystal size, 20–30 nm in diameter, and exhibit excellent photocatalytic activity. The degradation percentage of methyl blue reached a degree of 91% after 3 h under UV light irradiation, which was much better than the commercial SrTiO3 nanoparticles with the similar average size. The possible reason for the enhanced photocatalytic activity was also investigated.