Zhang Hui, Su Hui, Soldatov Mikhail A, Li Yuanli, Zhao Xu, Liu Meihuan, Zhou Wanlin, Zhang Xiuxiu, Sun Xuan, Xu Yanzhi, Yao Peng, Wei Shiqiang, Liu Qinghua
National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui, 230029, P. R. China.
The Smart Materials Research Institute, Southern Federal University, 178/24 Rostov-on-Don, Sladkova, 344090, Russia.
Small. 2021 Dec;17(49):e2105231. doi: 10.1002/smll.202105231. Epub 2021 Oct 28.
Accurately manipulating the electronic structure of metal active sites under working conditions is central to developing efficient and stable electrocatalysts in industrial water-alkali electrolyzers. However, the lack of an intuitive means to capture the evolution of metal sites during the reaction state inhibits the manipulation of its electronic structure. Here, atomically dispersed Ru single-sites on cobalt nanoparticles confined onto macro-microporous frameworks (M-Co NPs@Ru SAs/NC) with tunable electron coupling effect for efficient catalysis of alkaline hydrogen evolution reaction (HER) are constructed. Using operando X-ray absorption and infrared spectroscopies, a dynamic CoRu bond shrinkage with strong electron coupling effect under working conditions is identified, which significantly promotes the adsorption of water molecules and then accelerates its dissociation to form the key H* over Ru sites for high HER activity. The well-designed M-Co NPs@Ru SAs/NC delivers efficient HER performance with a small overpotential of 34 mV at 10 mA cm and a high turnover frequency of ≈4284 H h at -0.05 V, 40 times higher than that of the benchmark Pt/C. This work provides a new point of view to manipulate the electronic structure of the metal active sites for highly effective electrocatalysis processes.
在工业水电解槽中，精确调控工作条件下金属活性位点的电子结构对于开发高效稳定的电催化剂至关重要。然而，缺乏一种直观的方法来捕捉反应状态下金属位点的演变，这阻碍了对其电子结构的调控。在此，构建了负载在宏 - 微孔框架上的钴纳米颗粒上原子分散的钌单原子位点（M-Co NPs@Ru SAs/NC），其具有可调的电子耦合效应，用于高效催化碱性析氢反应（HER）。利用原位X射线吸收和红外光谱，发现在工作条件下动态的CoRu键收缩以及强电子耦合效应，这显著促进了水分子的吸附，进而加速其解离，在Ru位点上形成关键的H*，以实现高HER活性。精心设计的M-Co NPs@Ru SAs/NC具有高效的HER性能，在10 mA cm时过电位低至34 mV，在-0.05 V时周转频率高达≈4284 H h，比基准Pt/C高40倍。这项工作为调控金属活性位点的电子结构以实现高效电催化过程提供了新的视角。
