Preparation of Z‐scheme spherical BiOI/Fe2O3/BiOBr for water pollution treatment

Tetracycline drugs play a very important role in medical production and animal husbandry, but their residues are difficult to be naturally degraded in water environment, which causes a certain threat to human health. In this paper, the BiOI/Fe2O3/BiOBr composite photocatalytic material was successfully prepared to degrade tetracycline. The morphology and structure of the material were characterized by XRD, SEM, TEM, EDX, FT‐IR, UV–vis DRS, PL, EIS, photocurrent response, BET, and TOC, and the effect of the material on the degradation of tetracycline under simulated sunlight was investigated. The results showed that when the mass of BiOI/Fe2O3 and BiOBr was 1:1, reacted at 160°C for 16 h, BiOI/Fe2O3/BiOBr has the best degradation effect on tetracycline. The degradation rate of tetracycline can reach 85% in 180 min, and its kinetic rate constant is 2.16 and 1.8 times that of single BiOI and BiOI/Fe2O3, respectively. Based on the capture experiment of active substances, a Z‐scheme catalytic mechanism is proposed to analyze the degradation process of tetracycline, and BiOI/Fe2O3/BiOBr also showed a certain photocatalytic activity to other antibiotics and organic dyes in water.