Perspective on Photoelectrocatalytic Removal of Refractory Organic Pollutants in Water Systems

Refractory organic pollutants pose a great threat to natural ecosystems and humans due to their potential biotoxicity. This perspective discusses photoelectrocatalysis (PEC) technology and engineering for the removal of typical toxic refractory organic pollutants in water systems. Specifically, PEC is suitable for treating specific types of water with low concentrations of contaminants and high toxicity. In addition, it can be feasibly combined with other treatment systems. By analyzing the many advantages of PEC, the principles and features of PEC systems, including electro-assisted photocatalysis (EPC) and photoassisted electrocatalysis (PEC) systems, and their synergistic effects have been systematically clarified. In accordance, detailed PEC systems, including adsorption-enhanced PEC, photoelectro-Fenton techniques, selective PEC,and resource recovery, which can simultaneously remove organic pollutants and transform energy via PEC, have been further developed and discussed. In this perspective, the intermediates of PEC oxidation and toxicity studies have also been highlighted. Finally, challenges and perspectives for the development of PEC techniques have been proposed for engineering applications.