摘要
以电沉积的方式在商用镍网上成功制备出应用于碱性水电解析氧反应(OER)的多孔镍铁合金电极。通过调控电沉积量、镀液金属离子浓度等手段改变电极催化剂的沉积层形貌,制备出多级多孔枝晶状形貌镀层,研究了镀层结构、催化OER性能及稳定性。电流密度为10 mA·cm^(-2)时,电极析氧过电位仅为250 mV,Tafel斜率仅为35.8 mV·dec^(-1),催化活性超过商用Ir催化剂,C_(dl)值达到14.43 mF·cm^(-2),为空白镍网的10倍,具有优异的OER催化活性与较大电化学活性面积。同时,电沉积构筑的多孔形貌降低了反应电阻,镍铁合金电极的R_(ct)值(0.32Ω)远小于Ir/Ni电极(1.51Ω),拥有较快的催化反应动力学。在80℃、30%KOH、500 mA·cm^(-2)电流密度的条件下,水电解稳定运行75 h未出现显著衰减,表现出良好的稳定性。
We prepared porous nickel-iron alloy electrodes for alkaline water electrolysis oxygen evolution reaction(OER)by electrodeposition on a commercial nickel mesh.By regulating the quality of electrodeposition and the concentration of metal ions in the plating solution to change the deposition layer morphology,catalytic performance,and stability of the electrode catalyst,a multi-stage porous dendritic morphology plating was prepared.At a current density of 10 mA·cm^(-2),the electrode OER overpotential was only 250 mV,and the Tafel slope was only 35.8 mV·dec^(-1).The catalytic activity exceeded that of the commercial Ir catalyst,and the C_(dl) value reached 14.43 mF·cm^(-2),which was 10 times that of the blank Ni mesh,providing excellent OER catalytic activity with a large electrochemical active area.Meanwhile,the porous morphology constructed by electrodeposition reduced the reaction resistance,and the R_(ct) value of the NiFe alloy electrode(0.32Ω)was much smaller than that of the Ir/Ni electrode(1.51Ω),which possessed faster catalytic reaction kinetics.Under the conditions of 80℃,30%KOH and 500 mA·cm^(-2) current density,the stable operation of water electrolysis for 75 h did not show any significant degradation,which demonstrated good stability.
作者
李岳
闵洛夫
张文
许莉
王宇新
LI Yue;MIN Luofu;ZHANG Wen;XU Li;WANG Yuxin(State Key Laboratory of Chemical Engineering,Tianjin Key Laboratory of Membrane Science and Desalination Technology,School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China)
出处
《化学工业与工程》
CSCD
北大核心
2024年第5期51-60,共10页
Chemical Industry and Engineering
关键词
碱性水电解
镍铁合金
电极材料
析氧反应
alkaline water electrolysis
nickel-iron alloy
electrode materials
oxygen evolution reaction
