中国科学院大连化学物理研究所林坚团队报道了调节双原子催化剂中Ni和Fe原子间的金属间相互作用以促进CO₂电还原。相关研究成果于2024年8月8日发表于国际顶尖学术期刊《德国应用化学》。

双原子催化剂（DACs）由于催化位点增强的灵活性和双原子之间的协同效应，在电化学CO₂还原中的应用前景广阔。然而，精确控制原子距离和识别DACs的双原子结构以优化催化性能仍然是一个挑战。

该文中，研究人员报道了镍和铁原子对以三种不同的配置构建在氮掺杂碳载体上：NiFe隔离、NiFe-N桥和NiFe键。研究发现，与NiFe分离物和NiFe键合催化剂相比，NiN₄和FeN₄共享两个N原子的NiFe-N桥催化剂表现出优异的CO₂还原活性和良好的稳定性。

一系列表征和密度泛函理论计算表明，Ni和Fe原子之间具有适当距离的N桥NiFe位点可以发挥更明显的协同作用。它不仅调节了*COOH中间体的合适吸附强度，还促进了*CO的解吸，从而加速了CO₂电还原为CO。

该项工作为通过定制DACs的配位结构来增强催化作用提供了重要启示，并确定了相邻双原子之间的距离效应。

附：英文原文

Title: Tuning the Inter-Metal Interaction between Ni and Fe Atoms in Dual-Atom Catalysts to Boost CO2 Electroreduction

Author: Yang Chen, Jia Zhao, Xiaoli Pan, Lin Li, Zhounan Yu, Xiaodong Wang, Tianyi Ma, Sen Lin, Jian Lin

Issue&Volume: 2024-08-08

Abstract: Dual-atom catalysts (DACs) are promising for applications in electrochemical CO2 reduction due to the enhanced flexibility of the catalytic sites and the synergistic effect between dual atoms. However, precisely controlling the atomic distance and identifying the dual-atom configuration of DACs to optimize the catalytic performance remains a challenge. Here, the Ni and Fe atomic pairs were constructed on nitrogen-doped carbon support in three different configurations: NiFe-isolate, NiFe-N bridge, and NiFe bonding. It was found that the NiFe-N bridge catalyst with NiN4 and FeN4 sharing two N atoms exhibited superior CO2 reduction activity and promising stability when compared to the NiFe-isolate and NiFe-bonding catalysts. A series of characterizations and density functional theory calculations suggested that the N-bridged NiFe sites with an appropriate distance between Ni and Fe atoms can exert a more pronounced synergy. It not only regulated the suitable adsorption strength for the *COOH intermediate but also promoted the desorption of *CO, thus accelerating the CO2 electroreduction to CO. This work provides an important implication for the enhancement of catalysis by the tailoring of the coordination structure of DACs, with the identification of distance effect between neighboring dual atoms.

DOI: 10.1002/anie.202411543

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202411543