Synergistic Dual‐Single‐Atom Catalysis Driving Auto‐Catalytic Process Toward Oxidant‐Free Fenton‐Like Chemistry for Water Purification

Driving oxidant-free catalysis toward green and efficient Fenton-like chemistry for water purification has been developed as a research hotspots of priority concern. In this study, a Fe/Co dual single-atom catalyst (FeCo-DSAC) was synthesized with adjacent Fe and Co atoms coordinating with four nitrogen atoms on a carbon substrate, and applied in an oxidant-free system for pollutant degradation via an auto-catalytic pathway. Results showed dissolved oxygen (DO) was not the primary electron acceptor. In contrast, pollutants were adsorbed on electron-deficient sites, with electrons transferred to electron-rich dual Fe/Co sites via the carbon network, evidenced by a 0.6 oxidation state decrease and reduced open circuit potential. Intermediate analysis also confirmed the degradation process beyond adsorption process. In addition, density functional theory (DFT) calculations revealed that Fe doping not only introduced the additional active sites but also modulated the electronic structure of Co, making it more favorable for accepting the electrons from pollutants. This synergistic interaction facilitated effective contaminant degradation within the oxidant-free system. Furthermore, lifecycle analysis showed better environmental performance than conventional oxidant-added systems. This study provides new insights into the oxidant-free Fenton-like chemistry and advances the low-energy and low-chemical consumption water treatment technologies.