High-performance visible-light active Sr-doped porous LaFeO3 semiconductor prepared via sol–gel method

Abstract

In this work, we have successfully fabricated Sr-doped porous LaFeO₃ samples via sol–gel method. The results reveal that Sr²⁺ cation is effectively doped into LaFeO₃ crystal lattice substituting La³⁺ cation. The visible light catalytic performance of the materials was evaluated by the degradation of 2,4-dichlorophenol (2,4-DCP) and Rhodamine B (RhB). The amount-optimized Sr-doped porous LaFeO₃ sample exhibited outstanding visible-light catalytic performance for the degradation of the model pollutants compared to the porous LaFeO₃ alone. The enhanced performance was accredited to the enlarged surface area, absorption extension via the surface states of the introduced Sr²⁺ below the conduction band bottom of LaFeO₃, and promoted charge carrier’s separation as confirmed by various experiments. Experiments of radical trapping reveal that •OH species are dominant intermediate oxidants involved in the oxidation of 2,4-DCP and RhB over the optimized sample. This research will provide new routes for environmental remediation based on the LaFeO₃ semiconductor.