不对称配位操纵电子再分布实现高电流密度下电催化水氧化  

Manipulating electron redistribution induced by asymmetric coordination for electrocatalytic water oxidation at a high current density

作　　者：赵晟 胡峰 尹立杰 李林林 彭生杰 Sheng Zhao;Feng Hu;Lijie Yin;Linlin Li;Shengjie Peng(College of Materials Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China)

机构地区：[1]College of Materials Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China

出　　处：《Science Bulletin》2023年第13期1389-1398,M0004,共11页科学通报（英文版）

基　　金：supported by the National Natural Science Foundation of China(22075141 and 22101132);Scientific and Technological Innovation Special Fund for Carbon Peak and Carbon Neutrality of Jiangsu Province(BK20220039);Natural Science Foundation of Jiangsu Province(BK20221482 and BK20210311);China Postdoctoral Science Foundation(2021M691561 and 2021T140319);Jiangsu Postdoctoral Research Fund(2021K547C);the Fundamental Research Funds for the Central Universities(NS2023032);State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University(KF2312)。

摘　　要：作为目前最有前景的绿氢生产方式,电解水技术被研究者广泛关注.其中,电催化析氧反应(oxygen evolution reaction,OER)作为电解水的半反应,由于其缓慢的四电子转移步骤而成为电解水器件的能量瓶颈.高效的OER催化电极设计是解决该问题的有效方式.本文分析了OER催化剂中氧原子介导的电子重排与活性位点配位不对称性之间的构效关系.通过自发氧化还原反应,将镍离子引入到泡沫镍(NF)表面的FeWO_(4)中,以此破坏FeWO_(4)晶格中FeO_(6)八面体的对称性,并基于此调节Fe位点的电子结构.结构调控促进了钨酸盐适度重构成为具有高OER活性的羟基氧化物.在碱性环境中,具有不对称配位Fe位点的Fe_(0.53)Ni_(0.47)WO_(4)/NF自支撑电极在10 mA cm^(-2)的电流密度下,可获得170 mV的超低过电势,并在1000 mA cm^(-2)的高电流密度下可维持稳定500 h.这种新型OER催化电极为高活性电催化系统的设计提供了新的见解.Electronic structure manipulation with regard to active site coordination is an effective strategy to improve the electrocatalytic oxygen evolution reaction(OER)activity.Herein,we present the structure–activity relationship between oxygen-atom-mediated electron rearrangement and active site coordination asymmetry.Ni~(2+)ions are introduced to FeWO_(4)on Ni foam(NF)via self-substitution to break the symmetry of the FeO_(6)octahedron and regulate d-electron structure of Fe sites.Structural regulation optimizes the adsorption energy of hydroxyl on the Fe sites and promotes the partial formation of hydroxyl oxide with high OER activity on the tungstate surface.Fe_(0.53)Ni_(0.47)WO_4/NF with the asymmetric FeO_(6)octahedron of Fe sites can achieve an ultralow overpotential of 170 mV at 10 mA cm~(-2)and 240 mV at 1000 mA cm~(-2)with robust stability for 500 h at high current density under alkaline conditions.This research develops novel electrocatalysts with impressive OER performance and provides new insights into the design of highly active catalytic systems.

关 键 词：ELECTROCATALYSIS Oxygenevolutionreaction TUNGSTATE ELECTRODES Electron regulation 

分 类 号：TQ116.21[化学工程—无机化工] O643.36[理学—物理化学]