Gu Zhengxiang, Zhang Yechuan, Fu Yang, Hu Dandan, Peng Fang, Tang Yawen, Yang Huajun
School of Chemistry and Materials Science, Nanjing Normal University, 210023, Nanjing, China.
Jiangmen Laboratory of Carbon Science and Technology, Jiangmen, 529020, China.
Angew Chem Int Ed Engl. 2024 Sep 16;63(38):e202409125. doi: 10.1002/anie.202409125. Epub 2024 Aug 8.
Coordination engineering strategy for optimizing the catalytic performance of single-atom catalysts (SACs) has been rapidly developed over the last decade. However, previous reports on copper SACs for nitrate reduction reactions (NORR) have mostly focused on symmetric coordination configurations such as Cu-N and Cu-N. In addition, the mechanism in terms of the regulation of coordination environment and catalytic properties of SACs has not been well demonstrated. Herein, we disrupted the local symmetric structure of copper atoms by introducing unsaturated heteroatomic coordination of Cu-O and Cu-N to achieve the coordination desymmetrization of Cu-NO SACs. The Cu-NO SACs exhibit an efficient nitrate-to-ammonia conversion with a high FE of ~96.5 % and a yield rate of 3120 μg NH h cm at -0.60 V vs RHE. As indicated by in situ Raman spectra, the catalysts facilitate the accumulation of NO and the selective adsorption of *NO, which were further confirmed by the theoretical study of surface dipole moment and orbital hybridization. Our work illustrated the correlation between the coordination desymmetrization and the catalytic performance of copper SACs for NORR.
在过去十年中，用于优化单原子催化剂（SACs）催化性能的配位工程策略得到了迅速发展。然而，先前关于用于硝酸盐还原反应（NORR）的铜单原子催化剂的报道大多集中在对称配位构型上，如Cu-N和Cu-N。此外，关于单原子催化剂配位环境调控与催化性能之间的机制尚未得到很好的证明。在此，我们通过引入Cu-O和Cu-N的不饱和杂原子配位来破坏铜原子的局部对称结构，以实现Cu-NO单原子催化剂的配位去对称化。Cu-NO单原子催化剂在相对于可逆氢电极（RHE）为-0.60 V时，表现出高效的硝酸盐到氨的转化，法拉第效率（FE）高达约96.5%，产率为3120 μg NH₃ h⁻¹ cm⁻²。原位拉曼光谱表明，催化剂促进了NO₃⁻的积累和*NO的选择性吸附，表面偶极矩和轨道杂化的理论研究进一步证实了这一点。我们的工作阐明了配位去对称化与铜单原子催化剂用于NORR的催化性能之间的相关性。
