Molten salt electrosynthesis of self-supporting FeCoNi medium entropy alloy electrocatalysts for efficient oxygen evolution reactions  

作　　者：Xueqiang Zhang Zhongya Pang Jinjian Li Feng Tian Xuewen Xia Shun Chen Xing Yu Guangshi Li Chaoyi Chen Qian Xu Xionggang Lu Xingli Zou 

机构地区：[1]State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China [2]School of Metallurgical Engineering,College of Materials and Metallurgy,Guizhou University,Guiyang 550025,China [3]School of Materials Science,Shanghai Dianji University,Shanghai 201306,China

出　　处：《Journal of Materials Science & Technology》2024年第31期63-72,共10页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foundation of China(Nos.52022054,51974181,52004155,52004157,52374307,52304331,52334009);the National Key Research and Development Program of China(No.2022YFC2906100);the China Postdoctoral Science Foundation(No.2022M712023);the Science and Technology Commission of Shanghai Municipality(No.21DZ1208900);the Innovation Program of Shanghai Municipal Education Commission(No.2023ZKZD48);the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(No.TP2019041);the“Shuguang Program”supported by the Shanghai Education Development Foundation and the Shanghai Municipal Education Commission(No.21SG42).

摘　　要：High/medium entropy alloys(HEAs/MEAs)with high electrocatalytic activity have attracted great attention in water electrolysis applications.However,facile synthesis of self-supporting high/medium entropy alloys electrocatalysts with rich active sites through classical metallurgical methods is still a challenge.Here,a self-supporting porous FeCoNi MEA electrocatalyst with nanosheets-shaped surface for oxygen evolution reaction(OER)was prepared by a one-step electrochemical process from the metal oxides in molten CaCl_(2).The formation of the FeCoNi MEA is attributed to the oxides electro-reduction,high-temperature diffusion and solid solution.Additionally,the morphology and structure of the FeCoNi MEA can be precisely controlled by adjusting the electrolysis time and temperature.The electronic structure regulation and the reduced energy barrier of OER from the“cocktail effect”,the abundant exposed active sites brought by surface ultrathin nanosheets,the good electronic conductivity and electrochemical stability from the self-supporting structure enable the FeCoNi MEA electrode shows high-performance OER electrocatalysis,exhibiting a low overpotential of 233 mV at a current density of 10 mA cm^(-2),a low Tafel slope of 29.8 mV dec^(-1),and an excellent stability for over 500 h without any obvious structural destruction.This work demonstrates a facile one-step electrochemical metallurgical approach for fabricating self-supporting HEAs/MEAs electrocatalysts with nanosized surface for the application in water electrolysis.

关 键 词：Molten salt electrosynthesis FeCoNi medium entropy alloy Self-supporting electrocatalyst Nanosheets-shaped surface Oxygen evolution reactions 

分 类 号：TG1[金属学及工艺—金属学]