Regulation of Hydroxyl Radicals Generated by Fe−N−C in Heterogeneous Electro‐Fenton Reaction for Degradation of Organic Pollutants

Abstract Metal‐nitrogen‐carbon (M−N−C) materials display high catalytic activity for the oxygen reduction reaction (ORR) but poor durability which is considered to be related to the hydroxyl radicals (⋅OH) generated in‐situ. With reverse thinking, we try to increase the ⋅OH for the degradation of organic pollutants. In this study, the Fe−N−C catalyst was prepared by pyrolyzing the composite of tannin‐Fe film modified carboxylic CNT (TA−Fe‐CNT) and ZIF‐8. The ⋅OH generated during the ORR process was regulated by catalyst composition, applied potential, catalyst loading and pH. Under the optimum conditions, the Fe−N−C‐200 could degrade 86 % of methylene blue (MB) and reach a TOC removal rate of 21.2 % after 5 h through the heterogeneous electro‐Fenton (HEF) system. Overall, this study not only finds new application for M−N−C materials but also provides some useful information for improving their durability in proton exchange membrane fuel cell (PEMFC) from the opposite perspective.