Zhu Jian, Li Guangchao, Rokicińska Anna, Wang Zhenyu, Kuśtrowski Piotr, Lu Zhouguang, Das Shoubhik, Cool Pegie
Department of Chemistry, University of Antwerp, Antwerp, 2610, Belgium.
School of Metallurgy and Environment, Central South University, Changsha, 410083, China.
Small. 2025 Aug;21(31):e2505306. doi: 10.1002/smll.202505306. Epub 2025 Jun 6.
Bimetallic catalysts are appealing for electrochemical CO reduction reaction (ECO2RR), yet the introduction of bimetallic sites leads to an incomprehensive understanding of the metal atom interaction and catalytic mechanism. In this study, a series of bimetallic NiCu@NC catalysts with varied Ni to Cu weight ratios are prepared. The as-prepared NiCu@NC catalyst shows high carbon monoxide (CO) Faradaic efficiencies (FE) over 90% in a broad potential range of -0.7 to -1.1 V (vs reversible hydrogen electrode (RHE)) with an exceptional durability of CO selectivity over 80% and a high partial current density of -44 mA cm at an extremely high potential of -1.3 V (vs RHE). The distinguished CO selectivity and activity are primarily attributed to the integration of Ni and Cu, which lowers the d-band center position and reconstructs the electronic structure according to the valence band spectra. More specifically, the downshifted d-band center position weakens the interaction strength with the *CO intermediate on the NiCu@NC catalyst's surface during the ECO2RR process, resulting in fast *CO desorption and high CO selectivity. This study provides researchers with a new insight for designing and optimizing the electrocatalysts for ECO2RR.
双金属催化剂对电化学CO还原反应（ECO2RR）具有吸引力，然而双金属位点的引入导致对金属原子相互作用和催化机理的理解不全面。在本研究中，制备了一系列具有不同Ni与Cu重量比的双金属NiCu@NC催化剂。所制备的NiCu@NC催化剂在-0.7至-1.1 V（相对于可逆氢电极（RHE））的宽电位范围内显示出超过90%的一氧化碳（CO）法拉第效率（FE），具有超过80%的CO选择性的优异耐久性，并且在-1.3 V（相对于RHE）的极高电位下具有-44 mA cm的高部分电流密度。卓越的CO选择性和活性主要归因于Ni和Cu的整合，根据价带光谱，这降低了d带中心位置并重构了电子结构。更具体地说，下移的d带中心位置在ECO2RR过程中削弱了与NiCu@NC催化剂表面上CO中间体的相互作用强度，导致CO快速脱附和高CO选择性。本研究为研究人员设计和优化用于ECO2RR的电催化剂提供了新的见解。
