Solvothermal synthesis and visible light-driven photocatalytic degradation for tetracycline of Fe-doped SrTiO3

In this paper, Fe-doped SrTiO3 (FSTO) photocatalysts were successfully prepared via a facile solvothermal method, and their photocatalytic activities for degrading tetracycline (TC) under visible light irradiation were examined. It was found that doping Fe3+ into the lattice of SrTiO3 resulted in the formation of new absorption bands in the visible light region, and the energy band gap decreased from 3.2 eV to 2.6 eV with Fe3+ doping amounts of 0 to 5 wt%. The photocatalytic experimental results indicated that the as-prepared FSTO photocatalysts generate an extremely high enhancement in the TC degradation ratio compared to the pure SrTiO3 under visible light irradiation. In particular, the FSTO sample doped with 3% Fe exhibited the highest TC degradation ratio (71.6%) in 80 min, which is mainly attributed to the narrowed gap generated by the appropriate level of Fe3+ doping. This work suggests that this doping method should be applicable for exploiting other efficient visible light-driven photocatalysts with wide band gap semiconductors.