Radical-Mediated Dynamic Reconstruction of Ni–N–C Single-Atom Catalysts for Wide-Potential CO 2 -to-CO Electroreduction

作者：Jie Yang, Xue-Jia Wang, Jiaying He, Zhi‐Feng He, Guang Zeng, Shu‐Ming Xing, Dongao Zhang, Jin‐Chao Dong, Yimin Wei, Yaqiong Su, Yujing Ren, Jian‐Feng Li · 发表于：Journal of the American Chemical Society · 年份：2026 · DOI：10.1021/jacs.6c05980 · 被引用次数：2 · 研究领域：CO2 Reduction Techniques and Catalysts、Catalysts for Methane Reforming、Carbon dioxide utilization in catalysis

Ni–N–C single-atom catalysts are widely regarded as highly selective electrocatalysts for CO 2 reduction to CO; however, the catalytically relevant Ni species under operating conditions remains unclear. Here we provide in situ evidence that Ni–N–C catalysts undergo radical-mediated dynamic reconstruction during CO 2 electroreduction, which affords >90% CO Faradaic efficiency during a broad potential window (−0.6 to −1.5 V vs RHE). In situ X-ray absorption spectroscopy together with quasi-in situ electron paramagnetic resonance spectroscopy reveal a radical-driven evolution pathway in which isolated Ni–N 4 sites progressively aggregate into metallic Ni clusters via hydrogen-radical-induced processes, followed by hydroxyl-radical-mediated oxidation to form NiO x clusters; density functional theory calculations further support the key roles of these radicals in driving the transformation. Notably, the in situ-generated NiO x clusters exhibit lower free-energy barriers for all elementary steps of CO 2 -to-CO conversion than the initial Ni–N 4 sites. These results show that the sustained performance of Ni–N–C catalysts originates from radical-driven dynamic structural evolution rather than a static single-atom precursor, offering mechanistic insights into dynamic electrocatalysis for CO 2 reduction.