Three-dimensionally electrochemical oxidation technology: Current advances, challenges, and prospects for wastewater treatment

Three-dimensionally (3D) electrochemical oxidation technology has emerged as a groundbreaking advancement in electrochemical advanced oxidation processes (EAOPs), since the particle electrodes can enlarge the active sites for the generation of free radicals and expedite the mass transfer of pollutants within 3D reactor. However, several aspects of the 3D electrochemical system require further refinement, including the development and fabrication of affordable particle electrodes with high efficiency and stable performance, the rational design of 3D electrochemical reactor layout, and the optimization of processing parameter models. Herein, it presents a comprehensive and critical review on the evolution and application of 3D electrochemical systems, encompassing the characteristics of 3D electrochemical process, reactor configuration, kinetics of pollutant removal at varying primary operating parameters, underlying mechanisms, and approaches for regeneration of electrodes. We highlight the current challenges and issues encountered within this technology, particularly the contentious mechanisms surrounding the electrocatalytic performance of particle electrodes in pollutant degradation, which could potentially confound the development of 3D electrochemical technology towards industrial applications. Accordingly, we systematically describe relevant suggestions and potentially effective strategies, and offer perspectives on the application of 3D electrochemical technology in wastewater treatment. This review paper is expected to underpin the understanding and development of the 3D electrochemical oxidation technology for EAOPs in wastewater treatment.