Hydrothermal synthesis and visible-light-driven photocatalytic degradation for tetracycline of Mn-doped SrTiO3 nanocubes

Visible-light-driven manganese doped SrTiO 3 nanocubes with various manganese atomic percentages in the range of 3–7%, were prepared by a hydrothermal method. These obtained photocatalysts were systematically characterized by XRD, EDX, TEM, STEM, XPS, UV–vis, PL, EIS. The results demonstrated that the Mn 4+ has substituted into the lattice of SrTiO 3 nanocubes and the absorption onset shifted toward the visible region. It is beneficial to the photocatalytic degradation of tetracycline under the visible light irradiation. Interestingly, the optimal doping atomic percentages at 5% exhibited the highest degradation rates (66.7%) in 60   min. The high photocatalytic activity could be ascribed to the Mn doping adjustment the energy band of SrTiO 3 and the highly effective separation of photo-generated electron–hole pairs. Furthermore, the possible photocatalytic mechanism has been discussed based on the active species trapping experiments and ESR analysis.