Energy‐Efficient Electro‐Fenton Oxidation Enabled by CoCu Dual‐Atom Catalysts with High Oxygen Utilization
Wenxin Sun, Guoshuai Liu, Hua Zou, Shaobin Wang, Xiaoguang Duan, Shijie You
Abstract
Abstract The Electro‐Fenton (EF) technique offers a promising strategy for recalcitrant organic pollutant removal by coupling the two‐electron oxygen reduction reaction (2e – ORR) for H 2 O 2 synthesis with its subsequent activation to •OH via one‐electron (1e – ) reduction. To address the distinct favorable active sites and mismatched selectivity between 2e – ORR and 1e – H 2 O 2 activation, we develop an integrated 2 + 1e – tandem ORR catalyst with CoCu diatomic pairs (CoCu‐DACs‐CN) and cyano modification to improve oxygen capture and utilization efficiency (OUE, 39.8%). The CoCu‐DACs‐CN‐based EF system achieves 100.0% of bisphenol A (BPA) in 40.0 min with a high‐rate constant of k = 0.57 min −1 . Theoretical calculations indicate that the −CN moieties in CoCu‐DACs‐CN greatly facilitate O 2 adsorption, which further migrates to the Co site to proceed 2e – ORR with a reduced energy barrier. The generated H 2 O 2 spontaneously migrates to the surrounding Cu site for in situ activation to generate •OH. Long‐term operation of a CoCu‐DACs‐CN‐equipped flow‐cell device that maintains 100.0% bisphenol A removal even without O 2 /air pumping. Technoeconomic analysis indicates that the CoCu‐DACs‐CN‐based EF process effectively reduced electrical energy consumption by 74.4%, demonstrating its promise for energy‐efficient wastewater treatment.