Modified cathodes with carbon-based nanomaterials for electro-Fenton process

Electro-Fenton (EF) process is based on the continuous in situ production of hydrogen peroxide (H₂O₂) by a two-electron reduction of oxygen on cathode and the addition of ferrous ion to generate hydroxyl radical (^•OH) at the solution through Fenton’s reaction in acidic condition. Hence, cathode material has prominent effects on the H₂O₂ electro-generation efficiency and regeneration of ferrous ion. Carbonaceous materials are applied as suitable cathode in virtue of being highly conductive, stable, nontoxic, and commercially available. Besides, modification of cathode electrode with carbon-based nanomaterials (e.g., carbon nanotubes (CNTs), graphene, mesoporous carbon) can improve the electroactive surface area and the rate of oxygen mass transfer to the electrode, which increases the H₂O₂ electro-generation in the EF process. This chapter is to summarize the recent progress and advances in the modification of cathode electrode with carbon-based nanomaterials for EF process. The ability of different carbon-based nanomaterials to electro-generate H₂O₂ and degradation of pollutants is also discussed briefly.