Anion modulate the morphological and electronic structure of NiFe-based electrocatalyst for efficient urea oxidation-assisted water electrolysis  

作　　者：Duowen Ma Yansong Jia Yang Li Haibin Yang Fengzhi Wang Xinyu Zheng Guining Shao Qi Xiong Zhihao Shen Min Liu Zirui Lou Chaohua Gu 

机构地区：[1]School of Advanced Materials,Peking University Shenzhen Graduate School,Shenzhen 518055,China [2]Institute of Process Equipment,College of Energy Engineering,Zhejiang University,Hangzhou 310000,China [3]Hydrogen Energy Institute,Zhejiang University,Hangzhou 310000,China [4]Experimental Center,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310000,China [5]State Grid Zhejiang Electric Power CO.,LTD Research Institute,Hangzhou 310000,China

出　　处：《Journal of Materials Science & Technology》2024年第30期207-214,共8页材料科学技术(英文版)

基　　金：supported by the National Natural Science Foundation of China(No.22308322);the Science Foundation of Donghai Laboratory(No.DH-2022ZY0010);the R&D Project of State Grid Corporation of China(No.5108-202218280A-2-439-XG).

摘　　要：Renewable energy-driven water electrolysis is considered as an environmentally friendly hydrogen(H2)production technology.Replacing the oxygen evolution reaction(OER)with the urea oxidation reaction(UOR)is a more effective way to improve the energy efficiency of H2 generation.Herein,a highly effi-cient 2D NiFeMo-based UOR catalyst and 1D NiFeMo-based HER catalyst are prepared by adjusting the concentration of MoO_(4)^(-).The MoO_(4)^(-)can serve as the key regulator to adjust the balance between the electrolytic dissociation(α)of the reactants and the supersaturation(S)to modulate the morphological and electronic structure.The prepared 2D NiFeMo nanosheet UOR catalyst and 1D NiFeMo nanorod HER catalyst can achieve a current density of 100 mA cm^(−2)at a potential of 1.36 and 0.062 V,respectively.In a HER/UOR system,a cell voltage of 1.58 V is needed to achieve a current density of 100 mA cm^(−2).The HER/UOR system operated stably for over 60 h with 3 times the direct water electrolysis current den-sity.Moreover,the in situ Raman characterization coupled with XPS analysis clarifies that the addition of high-valence Mo can lower the transition energy barrier between the low and high oxidation state of Ni,which in turn lowers the overpotential of UOR.This work provides a novel strategy for synthesizing morphology-dependent electrocatalysts for different catalytic systems.

关 键 词：Urea oxidation reaction NiFe-based catalyst Hydrogen evolution Morphological and electronic structure Active sites 

分 类 号：O64[理学—物理化学]