Nanoscale SrFe0.5Ta0.5O3 double perovskite photocatalyst: Low-temperature solvothermal synthesis and photocatalytic NO oxidation performances

The nano-sized SrFe0.5Ta0.5O3 particles were successfully synthesized via a facial solvothermal process at 100 °C, and the strong interaction between the precursor cations and the oleate ions is the key factor to decrease the solvothermal temperature and control the particle size. [Display omitted] •Nanoscale SrFe0.5Ta0.5O3 particles with high crystallinity and purity.•Fabrication via a low-temperature solvothermal method.•Strong interactions between metal precursors and oleate ion.•Rapid transfer and separation of photo-generated electron-hole pairs. As a kind of the promising photocatalyst, double pervoskite oxides have the excellent light adsorption performance, highly stability, and favorable electronic property, but fabricating nanoscale double perovskite with high crystallinity and purity under facile preparation conditions is an attractive challenge. In this work, the low-temperature solvothermal method was introduced to fabricating double perovskite oxide SrFe0.5Ta0.5O3 at 100 °C. The as-prepared SrFe0.5Ta0.5O3 had the high crystallinity with particle size of ca. 31 nm. Under visible light irradiation, the pure SrFe0.5Ta0.5O3 photocatalyst exhibited the photocatalytic NO removal efficiency of ca. 35.1% which is much higher than that of Sr2FeTaO6. We found that the nanoscale size, high crystallinity, and purity of as-prepared SrFe0.5Ta0.5O3 particle can significantly increase the transfer and separation efficiency of the photogenerated charges from the bulk phase to surface. We also confirmed that the interaction between precursor cations and oleate ion was the key factor to decrease the solvothermal temperature and control the particle size. This work provided a novel strategy for preparing the Ta-containing perovskite photocatalyst under mild conditions.