Yin Haoran, Liu Xinqiang, Wang Lixia, Isimjan Tayirjan Taylor, Cai Dandan, Yang Xiulin
Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
Saudi Arabia Basic Industries Corporation (SABIC) at King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
Inorg Chem. 2024 Apr 15;63(15):7045-7052. doi: 10.1021/acs.inorgchem.4c00712. Epub 2024 Apr 3.
Doping metals and constructing heterostructures are pivotal strategies to enhance the electrocatalytic activity of metal-organic frameworks (MOFs). Nevertheless, effectively designing MOF-based catalysts that incorporate both doping and multiphase interfaces poses a significant challenge. In this study, a one-step Co-doped and CoO-modified Ni-MOF catalyst (named Ni NDC-Co/CP) with a thickness of approximately 5.0 nm was synthesized by a solvothermal-assisted etching growth strategy. Studies indicate that the formation of the Co-O-Ni-O-Co bond in Ni NDC-Co/CP was found to facilitate charge density redistribution more effectively than the Co-O-Ni bimetallic synergistic effect in NiCo NDC/CP. The designating Ni NDC-Co/CP achieved superior oxygen evolution reaction (OER) activity (245 mV @ 10 mA cm) and robust long stability (100 h @ 100 mA cm) in 1.0 M KOH. Furthermore, the Ni NDC-Co/CP||Pt/C/CP displays pregnant overall water splitting performance, achieving a current density of 10 mA cm at an ultralow voltage of 1.52 V, which is significantly lower than that of commercial electrolyzer using Pt/C and IrO electrode materials. In situ Raman spectroscopy elucidated the transformation of Ni NDC-Co to Ni(Co)OOH under an electric field. This study introduces a novel approach for the rational design of MOF-based OER electrocatalysts.
掺杂金属和构建异质结构是提高金属有机框架（MOF）电催化活性的关键策略。然而，有效设计同时包含掺杂和多相界面的基于MOF的催化剂面临重大挑战。在本研究中，通过溶剂热辅助蚀刻生长策略合成了一种厚度约为5.0 nm的一步法钴掺杂和氧化钴改性的镍基MOF催化剂（命名为Ni NDC-Co/CP）。研究表明，在Ni NDC-Co/CP中形成的Co-O-Ni-O-Co键比NiCo NDC/CP中的Co-O-Ni双金属协同效应更有效地促进了电荷密度的重新分布。所设计的Ni NDC-Co/CP在1.0 M KOH中实现了优异的析氧反应（OER）活性（10 mA cm时为245 mV）和强大的长期稳定性（100 mA cm时为100 h）。此外，Ni NDC-Co/CP||Pt/C/CP表现出出色的全水解性能，在1.52 V的超低电压下实现了10 mA cm的电流密度，这明显低于使用Pt/C和IrO电极材料的商业电解槽。原位拉曼光谱阐明了Ni NDC-Co在电场下转变为Ni(Co)OOH的过程。本研究为合理设计基于MOF的OER电催化剂引入了一种新方法。
