Recent progress in electrocatalytic selectivity in heterogeneous electro-Fenton processes

Abstract

The heterogeneous electro-Fenton process has attracted tremendous interest as a promising advanced oxidation reaction to treat refractory organic contaminants, but its practical application is still limited by a narrow pH response range, low oxidation, and unfavorable current efficiency. In this review, we focused on the electrocatalytic selectivity in electrodes, including hydrogen peroxide activation, cathodic oxygen reduction, and anodic water oxidation, which aimed to broaden the pH response range, and improve the utilization efficiency of hydrogen peroxide as well as promote the oxidation efficiency of homogeneous radicals in the system. Then, the investigation of key active sites under the interference of competitive reactions and structural reconstruction in the electrode was elaborated. Moreover, the coupling of electro-Fenton technologies with controllable electrocatalytic selectivity in electrodes for organic and inorganic pollutant removal was discussed. Finally, we concluded the review with a brief discussion of urgent challenges and further directions for electrodes in heterogeneous electro-Fenton processes with managed reactions.