Liu Xiaomeng, Fan Xing, Huang Hui, Gao Jianzhi
School of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062, China.
Institute of Functional Nano and Soft Materials Laboratory (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, 199 Ren'ai Road, Suzhou 215123, Jiangsu, China.
J Colloid Interface Sci. 2021 Apr;587:385-392. doi: 10.1016/j.jcis.2020.12.023. Epub 2020 Dec 13.
The bottleneck of electrochemical water splitting is the sluggish kinetics of oxygen evolution reaction (OER). Layered double hydroxides (LDHs) have been proposed as active and affordable electrocatalysts in OER. It has been reported that the activity of LDHs can be effectively tuned by doping of other metals. Despite previous experimental synthesis and improved catalytic performance, the in-depth OER mechanism on metal doped LDHs remains ambiguous. In the present work, transition metals (Cr, Mn and Co) doped NiFe LDHs were designed to investigate the doping effect in OER by both experimental analysis and density functional theory calculations. Based on experimental results, the intrinsic OER activity is Cr-NiFe LDHs > Co-NiFe LDHs > Mn-NiFe LDHs > NiFe LDHs, while the enhanced catalytic performance upon doping can be attributed to the interface effect, which results in the tuning of the binding energies of the intermediate states in OER.
电化学水分解的瓶颈在于析氧反应（OER）缓慢的动力学。层状双氢氧化物（LDHs）已被提议作为OER中活性且经济实惠的电催化剂。据报道，通过掺杂其他金属可以有效调节LDHs的活性。尽管之前有实验合成和催化性能的改进，但金属掺杂LDHs上深入的OER机理仍不明确。在本工作中，通过实验分析和密度泛函理论计算设计了过渡金属（Cr、Mn和Co）掺杂的NiFe LDHs，以研究掺杂对OER的影响。基于实验结果，本征OER活性为Cr-NiFe LDHs > Co-NiFe LDHs > Mn-NiFe LDHs > NiFe LDHs，而掺杂后催化性能的增强可归因于界面效应，这导致了OER中间态结合能的调节。
