Liu Xinqiang, Su Shibiao, Yin Haoran, Zhang Shifan, Isimjan Tayirjan Taylor, Huang Jin, Yang Xiulin, Cai Dandan
School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai, 519082, P. R. China.
Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin, 541004, P. R. China.
Small. 2024 Mar;20(10):e2306085. doi: 10.1002/smll.202306085. Epub 2023 Oct 24.
Bimetallic metal-organic framework (BMOF) exhibits better electrocatalytic performance than mono-MOF, but deciphering the precise anchoring of foreign atoms and revealing the underlying mechanisms at the atomic level remains a major challenge. Herein, a novel binuclear NiFe-MOF with precise anchoring of Fe sites is synthesized. The low-crystallinity (LC)-NiFe -MOF exhibited abundant unsaturated active sites and demonstrated excellent electrocatalytic oxygen evolution reaction (OER) performance. It achieved an ultralow overpotential of 230 mV at 10 mA cm and a Tafel slope of 41 mV dec . Using a combination of modulating crystallinity, X-ray absorption spectroscopy, and theoretical calculations, the accurate metal sequence of BMOF and the synergistic effect of the active sites are identified, revealing that the adjacent active site plays a significant role in regulating the catalytic performance of the endmost active site. The proposed model of BMOF electrocatalysts facilitates the investigation of efficient OER electrocatalysts and the related catalytic mechanisms.
双金属金属有机框架（BMOF）表现出比单金属有机框架更好的电催化性能，但在原子水平上解析外来原子的精确锚定并揭示其潜在机制仍然是一个重大挑战。在此，合成了一种具有精确铁位点锚定的新型双核镍铁金属有机框架。低结晶度（LC）-镍铁金属有机框架表现出丰富的不饱和活性位点，并展示出优异的电催化析氧反应（OER）性能。在10 mA cm时实现了230 mV的超低过电位和41 mV dec的塔菲尔斜率。通过结合调节结晶度、X射线吸收光谱和理论计算，确定了BMOF的精确金属序列和活性位点的协同效应，揭示了相邻活性位点在调节最末端活性位点的催化性能方面发挥着重要作用。所提出的BMOF电催化剂模型有助于高效OER电催化剂及其相关催化机制的研究。
