Recent advances in oxidant-involved photoelectrochemical systems for sustainable wastewater treatment: mechanisms, applications, and perspectives

This review assesses oxidant-involved photoelectrochemical (PEC) systems for sustainable wastewater treatment. The development and modification of semiconductors for photoelectrode fabrication are discussed, while elucidating the underlying mechanisms, treatment performance, and practical applications of various oxidant-involved PEC systems, including PEC/chloride, PEC/hydrogen peroxide, PEC/persulfate, and PEC/sulfite. Key challenges, including photoelectrode fabrication, material stability and reusability, wastewater matrix interference, byproduct formation, and scalability, are critically examined, and perspectives for practical implementation are provided.