Zhang Chaofan, Li Na, Liu Yuefeng, Zhang Ting, Zhang Riguang, Zhao Zhongkui
State Key Laboratory of Fine Chemicals, Department of Catalysis Chemistry and Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian, 116024, P. R. China.
State Key Laboratory of Clean and Efficient Coal Utilization, Key Laboratory of Coal Science and Technology, Taiyuan University of Technology, Taiyuan, Shanxi, 030024, P. R. China.
Small. 2025 Jan;21(1):e2407463. doi: 10.1002/smll.202407463. Epub 2024 Nov 5.
Benefiting from the synergism between adjacent bimetallic atoms, in comparison with single atom catalysts, the dual atom catalysts have displayed great potential in electrocatalytic CO reduction reaction (CORR). However, the further modulation of the electronic structure of dual atom sites to enhance CORR performance still remains a challenge. Herein, an atomically dispersed oxygen-bridged NiNO/NC catalyst with unique Ni-O-Ni sites is successfully synthesized through the microwave pyrolysis of the supported mixture containing the dinuclear nickel phthalocyanine and glucose on N-doped carbon nanosheets. Experiments and density functional theory calculation reveal that the Ni-O-Ni sites can adsorb H from the KHCO electrolyte to in situ-form the unique Ni-OH-Ni sites without Ni─Ni bonding interaction, which effectively lowers the energy barrier towards the formation of *COOH from CO. As a result, the NiNOH/NC catalyst exhibits a 99.4% of CO Faradaic efficiency with a 32.4 mA·cm of CO partial current density at -0.7 V versus RHE in H-cell, much superior to the NiN/NC with a Ni-Ni bonding interaction prepared by a similar procedure to that for NiNO/NC but replacing microwave pyrolysis by a traditional heating process.
得益于相邻双金属原子之间的协同作用，与单原子催化剂相比，双原子催化剂在电催化CO还原反应（CORR）中展现出了巨大潜力。然而，进一步调控双原子位点的电子结构以提高CORR性能仍然是一个挑战。在此，通过对负载在氮掺杂碳纳米片上的含有双核镍酞菁和葡萄糖的混合物进行微波热解，成功合成了具有独特Ni-O-Ni位点的原子分散的氧桥连NiNO/NC催化剂。实验和密度泛函理论计算表明，Ni-O-Ni位点可以从KHCO电解液中吸附H，原位形成独特的无Ni─Ni键相互作用的Ni-OH-Ni位点，这有效地降低了由CO形成*COOH的能垒。结果，在H型电解池中，相对于可逆氢电极（RHE），NiNOH/NC催化剂在-0.7 V时表现出99.4%的CO法拉第效率和32.4 mA·cm的CO分电流密度，远优于通过与制备NiNO/NC类似的方法制备但用传统加热过程代替微波热解的具有Ni-Ni键相互作用的NiN/NC催化剂。
