Kong Shaoxi, Lu Mengfei, Yan Shicheng, Zou Zhigang
Collaborative Innovation Center of Advanced Microstructures, Eco-Materials and Renewable Energy Research Center (ERERC), College of Engineering and Applied Sciences, Nanjing University, No. 22, Hankou Road, Nanjing, Jiangsu 210093, P. R. China.
National Laboratory of Solid State Microstructures, Jiangsu Key Laboratory for Nano Technology, School of Physics, Nanjing University, No. 22 Hankou Road, Nanjing, Jiangsu 210093, P. R. China.
Dalton Trans. 2022 Nov 15;51(44):16890-16897. doi: 10.1039/d2dt02908a.
An effective pathway to cope with the sluggish oxygen evolution reaction (OER) is to accelerate the electron transfer kinetics. Transition metal with high valence states doping can accelerate the reaction kinetics to afford high inherent activity. Herein, a novel trimetallic NiFeCr nanoalloy as an OER electrocatalyst is synthesized by replacing partial Fe in the NiFe alloy with Cr. In the OER process, Cr leached from the surface layer of the NiFeCr alloy to form a core-shell NiFeCr@NiFeOOH structure. The electrons from the OER intermediates were significantly accelerated by the high-valence Cr as an electron acceptor at the core-shell interface. As a result, NiFeCr@NiFeOOH exhibited excellent OER performances with a low overpotential of 209 mV at 25 mA cm in 1.0 M KOH on conductive carbon paper, outperforming the NiFe alloy without Cr doping. Our work provides a new strategy to design and synthesize the NiFe-based alloy with high OER activity.
应对缓慢析氧反应（OER）的有效途径是加速电子转移动力学。高价态过渡金属掺杂可以加速反应动力学，从而提供高本征活性。在此，通过用Cr替代NiFe合金中的部分Fe，合成了一种新型三金属NiFeCr纳米合金作为OER电催化剂。在OER过程中，Cr从NiFeCr合金的表层浸出，形成核壳结构的NiFeCr@NiFeOOH。作为电子受体的高价Cr在核壳界面显著加速了来自OER中间体的电子转移。结果，NiFeCr@NiFeOOH在1.0 M KOH中于导电碳纸上在25 mA cm时表现出优异的OER性能，过电位低至209 mV，优于未掺杂Cr的NiFe合金。我们的工作为设计和合成具有高OER活性的NiFe基合金提供了一种新策略。
