Zhao Xu, Li Xiangyang, An Lulu, Zheng Lirong, Yang Jinlong, Wang Deli
Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), Hubei Key Laboratory of Material Chemistry and Service Failure, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, P. R. China.
Hefei National Laboratory for Physical Sciences at the Microscale, Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
Angew Chem Int Ed Engl. 2022 Aug 8;61(32):e202206588. doi: 10.1002/anie.202206588. Epub 2022 Jul 4.
The valence-electron arrangement of heterogeneous catalysts can significantly affect the binding behavior of absorbates. However, it remains a challenge to understand the role of the valence-electron arrangement in electrocatalysis, which limits its utilization as a tool to design efficient electrocatalysts. Here, we describe experiments in which the valence-electron arrangement of Ni active centers for hydrogen oxidation is controlled precisely by using Ni-vacancy-enriched Ni N as a platform. These Ni vacancies can promote the valence-electron delocalization of OH-adsorption centers to enhance the Ni ds-O 2p valence-electron-orbital interaction with elevated OH adsorption. Meanwhile, the deficit of valence-electrons of H-adsorption centers at Ni vacancies can lower Ni ds-H 1s interaction with weakened H binding. Relative to Ni N poor in vacancies, the Ni-vacancy-enriched Ni N showed a mass activity enhanced by 15-fold. This strategy paves a rational way to design efficient catalysts by finely tuning the valence-electron arrangement.
多相催化剂的价电子排布会显著影响吸附质的吸附行为。然而，理解价电子排布在电催化中的作用仍然是一项挑战，这限制了其作为设计高效电催化剂工具的应用。在此，我们描述了一些实验，其中通过使用富含镍空位的Ni N作为平台，精确控制用于氢氧化的镍活性中心的价电子排布。这些镍空位可促进OH吸附中心的价电子离域，以增强Ni dσ-O 2p价电子轨道相互作用，从而提高OH吸附。同时，镍空位处H吸附中心的价电子不足会削弱Ni dσ-H 1s相互作用，降低H的吸附。相对于空位较少的Ni N，富含镍空位的Ni N的质量活性提高了15倍。该策略为通过精细调节价电子排布来设计高效催化剂铺平了一条合理的道路。
