Efficient Degradation of Rhodamine B with the BiOCl/Bi<sub>2</sub>Fe<sub>4</sub>O<sub>9</sub> Heterojunction Photocatalyst
Shuyan Qi, Ling Guan, Ruiyan Zhang, Shanqiang Wu, Kaiyao Zhang
Abstract
BiOCl/Bi 2 Fe 4 O 9 photocatalyst was prepared by a coprecipitation–hydrothermal method. The heterojunction structure generated by the composite of BiOCl and Bi 2 Fe 4 O 9 reduced the electron–hole recombination efficiency and improved the degradation rate of RhB. At 240 min, 20% BiOCl/Bi 2 Fe 4 O 9 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 Bi 2 Fe 4 O 9 and BiOCl, respectively. The main active substance of the photocatalytic degradation of dyes was superoxide radical O 2 – ·. Five cycles of the experiment proved the relative stability of BiOCl/Bi 2 Fe 4 O 9 .