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.

Keywords

• Porous LaFeO3
• hydroxyl radical
• 2,4-DCP
• RhB
• sol–gel method