T-mode adsorption and photoelectrocatalysis degradation for acyclovir on CuMn2O4@WO3/g-C3N4 electrode

Abuse of antiviral drugs caused by overtreatment has attracted significant attention because of its widespread distribution in natural water. Here, we developed a novel CuMn2O4@WO3/g-C3N4 ((CMNW)CN) cathode electrode with CuMn2O4 (CMO) as electrocatalytic electrode and WO3/g-C3N4 (WCN) as photocatalytic electrode to realize the photoelectrocatalysis degradation for acyclovir in a Photo-Bio-Electro-Fenton (PBEF) system. The electrochemical performance, surface morphology and photoelectrocatalysis activity of the (CMNW)CN electrode were investigated, showing excellent redox performance and efficient electron transfer efficiency. Density functional theory (DFT) calculations confirmed that the CMO electrode adsorbed peroxymonosulfate (PMS) through a unique T-mode, increasing the photochemical activity and the ability of donor giving electrons of (CMNW)CN electrode, generating photogenerated electron-hole pairs under light conditions. Three proposed degradation pathways with eight degradation intermediates and the underlying reaction mechanism of acyclovir were identified in our research. Degradation efficiency of acyclovir in the PBEF reached 100% within 30 min, with high cycle stability. Our results demonstrated a new method for in-situ T-mode adsorption and photoelectrocatalysis degradation of acyclovir on (CMNW)CN electrode, especially the non-toxic effluents of PBEF proved the green environment-friendly degradation process of drug residues.