Preparation and characterization of BiOBr/CuFe2O4 composite catalyst and constitute photo-Fenton system for degradation of polyacrylamide under visible light

A simple hydrothermal synthesis method was employed to fabricate a BiOBr/CuFe2O4 composite photo-Fenton catalyst with visible light response in this study. The effects of the CuFe2O4 dosage, the concentration of polyacrylamide (PAM), the reaction time, the pH of the initial solution and the light source on the reaction results were investigated. Under the visible light, ultraviolet light and sunlight irradiation, the chemical oxygen demand (COD) removal rate of PAM (250 mg/L) reached 62.43%, 69.21%, 65.17%, respectively. Simultaneously, the structure, morphology and optical properties were characterized. The improved activity of BiOBr/CuFe2O4 can be attributed to formation of Z-type heterojunction, synergistic effect of photocatalysis and Fenton catalysis. The free radical capture experiments show that •O2−, h+ and •OH are all active species of BiOBr/CuFe2O4 for decomposing PAM in photo-Fenton reactions. Finally, a possible electron transfer mechanism was proposed through the fitting of Mott-Schottky curve and Taut-plot curves. In this work, a BiOBr/CuFe2O4 photo-Fenton catalyst was prepared and shows that enhanced photo-Fenton degradation performance for polyacrylamide. The characterization results show that photo-Fenton synergy and Z-type heterojunction formation are the main reasons for improving polyacrylamide degradation, at the same time, the catalyst has good adaptability to different light conditions. [Display omitted] •A novel photo -Fenton BiOBr/CuFe2O4 catalyst was prepared.•BiOBr/CuFe2O4 displays good photo-Fenton degradation activity for polyacrylamide.•Special Z-type heterojunction accelerate the degradation of polyacrylamide.•BiOBr/CuFe2O4 has wider spectral response range.