Synthesis and photoactivity of hetero-nanostructured SrTiO3

A SrTiO3 hetero-nanostructure was synthesized via solvothermal reaction using a protonated trititanate nanowire (H2Ti3O7) and strontium hydroxide octahydrate (Sr(OH)2·8H2O) in an ethanol/water mixed solvent system. The ethanol to deionized water volume ratio was the controlling parameters for determining the phase formation and the particle size of the SrTiO3 nanocrystals. Single-phase cubic perovskite SrTiO3 began to form at 120°C in a mixed solvent containing >40% ethanol by volume. Field emission scanning electron microscopy (FE-SEM) and high resolution transmission electron microscopy (HRTEM) showed that the as-prepared SrTiO3 retained its wire-like (1D) morphology with nanocrystals (0D) on the surface. The synthetic mechanism of the 0D-1D SrTiO3 hetero-nanostructures was demonstrated by topochemical reaction from dielectric tuning of the mixed solvent and the correlation between the crystal structures of SrTiO3 and H2Ti3O7. Using as-prepared SrTiO3 nanowires, the photocatalytic activity for the degradation of a rhodamine B dye solution was evaluated under UV irradiation and compared to SrTiO3 powder from solid state reaction.