Recent advances in photoelectrocatalytic advanced oxidation processes: From mechanism understanding to catalyst design and actual applications

The photoelectrocatalytic (PEC) advanced oxidation process is a promising water treatment technology. Compared with traditional water treatment technology, the PEC process has the advantages of high efficiency, low energy consumption, and more thorough mineralization of refractory pollutants, which has attracted continuous attention worldwide. However, there is still a large gap between current research and the actual application of the PEC process. As mentioned above, this paper aimed to systematically review the basic principles of the PEC process and summarize the generation pathways of active species based on hole oxidation and electron reduction reactions. The design and modification strategies of catalysts based on enhanced light absorption and charge separation efficiency are discussed specifically, and recent progress in catalysts is introduced. Furthermore, to achieve a better application of the PEC process, reactor design strategies based on improving the photon utilization rate, enhancing the pollutant mass transfer, and coupling the PEC process with an adsorption or separation process were proposed. Finally, the problems and challenges faced by the PEC process are summarized and proposed to provide ideas for further development of this technology in the future.