Advances in the electrochemical degradation of environmental persistent organochlorine pollutants: materials, mechanisms, and applications

Pollution from persistent organic chlorinated pollutants (POCPs) in water environments is attributable to historical reasons and the lack of effective discharge regulations. Electrochemical degradation of POCPs, as a key study for POCP degradation, involves the use of electrons as reducing or oxidizing agents. The occurrence of this degradation depends on the environmental characteristics of the POCPs, the electrochemical materials used, and the technology and mechanisms involved. Furthermore, regarding the development of new materials and technologies, such as micro-, nano-, and atomic-sized materials, the degradation of POCPs achieves higher degradation efficiency and maximizes current utilization efficiency. In this review article, we first summarize the current status and future opportunities of the electrochemical degradation of POCPs. Environmental characteristics of POCPs facilitate a comparison of POCP degradation, and a comparison of electrochemical materials and their methods is made. Subsequently, we discuss technologies for the electrochemical degradation of POCPs from three aspects: oxidation, reduction, and a combination of oxidation and reduction. Moreover, the mechanisms were generalized in terms of molecular structure, electrode materials, and solution environment. In addition to maximizing the intrinsic enhancement factors of degradation, strategies to improve environmental accessibilities are equally important. This review article aims to effectively guide the advancement of POCP degradation and the remediation of environmental water pollution.