Song Jian, Lei Xue, Mu Jiali, Li Jingwei, Song Xiangen, Yan Li, Ding Yunjie
Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, 116023, China.
University of Chinese Academy of Sciences, Beijing, 100049, China.
Small. 2023 Dec;19(52):e2305666. doi: 10.1002/smll.202305666. Epub 2023 Aug 27.
Tuning the coordination environment of the metal center in metal-nitrogen-carbon (M-N-C) single-atom catalysts via heteroatom-doping (oxygen, phosphorus, sulfur, etc.) is effective for promoting electrocatalytic CO reduction reaction (CO RR). However, few studies are investigated establishing efficient CO reduction by introducing boron (B) atoms to regulate the M-N-C structure. Herein, a B-C N self-sacrifice strategy is developed to synthesize B, N co-coordinated Ni single atom catalyst (Ni-BNC). X-ray absorption spectroscopy and high-angle annular dark field scanning transmission electron microscopy confirm the structure (Ni-N B/C). The Ni-BNC catalyst presents a maximum CO Faradaic efficiency (FE ) of 98.8% and a large CO current density (j ) of -62.9 mA cm at -0.75 and -1.05 V versus reversible hydrogen electrode, respectively. Furthermore, FE could be maintained above 95% in a wide range of potential windows from -0.65 to -1.05 V. In situ experiments and density functional theory calculations demonstrate the Ni-BNC catalyst with B atoms coordinated to the central Ni atoms could significantly reduce the energy barrier for the conversion of *CO to *COOH, leading to excellent CO RR performance.
通过杂原子掺杂（氧、磷、硫等）来调节金属-氮-碳（M-N-C）单原子催化剂中金属中心的配位环境，对促进电催化CO还原反应（CO RR）是有效的。然而，通过引入硼（B）原子来调控M-N-C结构以实现高效CO还原的研究却很少。在此，我们开发了一种B-C N自牺牲策略来合成B、N共配位的Ni单原子催化剂（Ni-BNC）。X射线吸收光谱和高角度环形暗场扫描透射电子显微镜证实了其结构（Ni-N B/C）。Ni-BNC催化剂在相对于可逆氢电极-0.75和-1.05 V时，分别呈现出98.8%的最大CO法拉第效率（FE）和-62.9 mA cm²的大CO电流密度（j）。此外，在-0.65至-1.05 V的宽电位窗口内，FE可保持在95%以上。原位实验和密度泛函理论计算表明，B原子与中心Ni原子配位的Ni-BNC催化剂可显著降低CO转化为COOH的能垒，从而导致优异的CO RR性能。
