Iodine-Induced Redirection of Active Sources in Cu-Based Catalysts during Efficient and Stable Water Oxidation

• DOI: 10.1021/jacs.5c01897
• Publication Date: 2025-04-26T02:12:45Z
• Authors: Mingzheng Gu; Ling Jiang; Hao Wang; Qiao Chen; Yixin Hao; Linlin Li; Feng Hu; Xiaojun Zhang; Yuping Wu; Guangfeng Wang; Shengjie Peng

Enhancing the mechanistic regulation of oxygen evolution reaction (OER) is crucial for developing efficient and stable electrocatalysts. However, dynamic variation surface structure during electrocatalytic process limits accurate identification active source underlying mechanism. Herein, we report an iodine-doping strategy to direct reconstruction species in CuS catalysts toward unconventional vacancy oxidation mechanism, thereby overcoming activity stability limitations. Mechanistic analysis indicates that electronic manipulation, weak coordination Cu-S bonds, lattice distortion induced by facilitate thermodynamically favorable Cu2+ Cu3+ OER. The decisively formed vacancies are emphasized as a genuine promote hydroxyl adsorption, with hypervalent Cu acting auxiliary sites accelerate deprotonation strengthening Cu-O covalent. Consequently, optimal iodine-doped exhibits reduced overpotential 189 mV at 10 mA cm-2 superb prolonging 1250 h. When used bifunctional electrode membrane assembly electrolyzer, it also low voltage 1.65 V 1 A cm-2, electrolysis durability 480 h hydrogen cost US$1.70/kg H2, outperforming 2026 targets set U.S. Department Energy.