Significantly improved photocatalytic activity of the SnO₂/BiFeO₃ heterojunction for pollutant degradation and mechanism

Herein, motivated with narrow/wide-bandgap heterojunction materials as one of the perfect solutions, we separately synthesized BiFeO₃ (BFO) and SnO₂ nanoparticles; then coupled them in various weight percentages to obtain nanocomposites with efficient contacts for visible light 2,4-DCP and RhB degradation and effectively reduced charge recombination. The material of interest, i.e., with six weight percentage coupling of SnO₂ (i.e., 6SO/94BFO), endorsed superior photoactivity for 2,4-DCP and RhB degradation. In addition, under the visible light irradiation, this photocatalyst degraded 87.2% of RhB and 65.1% of 2,4-DCP in 2h, which compared to pristine BiFeO₃ nanoparticles are about 2.6- and 2.7-times enhancements, respectively. The photoluminescence spectroscopy and mechanism model showed a substantial interface between BiFeO₃ and SnO₂ and unfeasible electron-holes recombination. The electrons and holes are entirely utilized to produce superoxides and •OH radicals, respectively, predicting enhanced visible-light photodegradation. Overall, this work offers novel narrow/wide-bandgap heterojunction nanocomposites as feasible aspirants for pollution control and effective visible light photodegradation of chlorinated compounds.