Efficient Degradation of Rhodamine B with the BiOCl/Bi₂Fe₄O₉ Heterojunction Photocatalyst

Abstract

BiOCl/Bi₂Fe₄O₉ photocatalyst was prepared by a coprecipitation-hydrothermal method. The heterojunction structure generated by the composite of BiOCl and Bi₂Fe₄O₉ reduced the electron-hole recombination efficiency and improved the degradation rate of RhB. At 240 min, 20% BiOCl/Bi₂Fe₄O₉ represented the excellent degradation effect on 10 mg/L RhB; the degradation efficiency reached 99.56%; and the reaction rate constant was 0.01534 min^-1, which was 5.76 times and 6.06 times that of Bi₂Fe₄O₉ and BiOCl, respectively. The main active substance of the photocatalytic degradation of dyes was superoxide radical O₂^-·. Five cycles of the experiment proved the relative stability of BiOCl/Bi₂Fe₄O₉.