Preparation of MoS2 and Fe3O4/Fe2O3 composites and their photo-Fenton degradation roxarsone efficacy study

Fenton technology is effective in removing high-risk roxarsone (ROX) from the environment. In this study, MoS 2 -modified magnetic iron oxides were successfully synthesized to serve as catalysts for the photo-Fenton system to efficiently degrade ROX. Under light illumination, these catalysts demonstrated strong arsenic adsorption characteristics and photocatalytic activity. The catalyst 6Mo-Fe achieved a 96.15% removal of 20 mg/L ROX and an 88.95% removal of total arsenic within 120 minutes. The study evaluated the effects of catalyst dosage, H 2 O 2 dosage, initial pH, and common anions on the degradation efficiency. The integration of MoS 2 significantly improved the forbidden band width, light absorption capacity, and electrochemical impedance of iron oxides, facilitating the separation and transfer of charge carriers. MoS 2 provided abundant Mo 4+ reduction sites for Fe 3+ , which, in conjunction with the photocatalytic reaction, promoted the cyclic conversion between Fe 3+ and Fe 2+ , thereby markedly increasing the reaction rate. This study presents an innovative approach using MoS 2 -modified iron oxides for the sustainable and eco-friendly degradation of organoarsenic compounds.