Photo-Fenton reaction for the degradation of tetracycline hydrochloride using a FeWO4/BiOCl nanocomposite

Heterogeneous photo-Fenton technology combines photocatalytic and Fenton reactions to utilize solar energy and H2O2 efficiently, which is currently one of the most effective technologies for removing organic pollutants. In this work, FeWO4/BiOCl composite with different BiOCl contents was successfully produced by a two-step hydrothermal method. The photo-Fenton efficiency of the synthesized materials was assessed by the degradation of tetracycline hydrochloride (TCH) under simulated solar irradiation. The as-synthesized FeWO4/BiOCl composite exhibited significantly higher photocatalytic performances than individual semiconductors in the presence of H2O2 under simulated solar irradiation, and the apparent reaction rate constant reached as high as 0.0531 min−1, which was 4 times and 1.5 times higher than that of BiOCl and FeWO4, respectively. The effects of pH, TCH concentration, H2O2 concentration, and catalyst dosage on TCH degradation were investigated to identify the optimized reaction conditions. The excellent recyclability of FeWO4/BiOCl composite towards TCH photo-Fenton degradation was also shown. Photoelectrochemical analysis was performed to check the effective charge separation. The remarkably enhanced photo-Fenton catalytic performance of FeWO4/BiOCl composite was ascribed to effective charge separation and the production of more ·OH radicals. The FeWO4/BiOCl composite has proven to be a highly efficient and promising catalyst for Fenton-like processes to deal with practical environmental issues.