深共晶溶剂中电沉积制备Co-Fe-Gd/NF电极及其析氢性能研究

Preparation of Co-Fe-Gd/NF electrodes by electrodeposition indeep eutectic solvents and study of their hydrogen precipitation properties

为了制备出在碱性环境中具备高效能的廉价析氢电极催化剂,选择不同的沉积电位在氯化胆碱-尿素(ChCl-urea)中电沉积制备出五种Co-Fe-Gd/NF电极催化剂。通过扫描电镜(SEM)和光谱仪(EDX)对电极表面形貌、元素含量及分布情况进行表征,X射线光电子能谱(XPS)对电极表面化学性质进行表征。结合线性扫描伏安法(LSV)、电化学阻抗技术(EIS)和循环伏安法(CV)电化学测试结果,表明-1.24 V沉积电位下制备的Co-Fe-Gd/NF-3电极具备优异的析氢催化性能,在10 mA·cm^(-2)时的过电位仅为71 mV,最小的塔菲尔斜率(45 mV·dec^(-1))与电荷转移电阻(0.28503Ω·cm^(-2))表明其具备更快的析氢反应动力学过程,电化学活性表面积(ECSA)最大为390.5,为析氢过程提供更多的反应活性位点。对电极进行循环伏安耐久性测试与计时电流法(I-t)测试,结果表明Co-Fe-Gd/NF-3电极催化剂在碱性环境中稳定性良好。

In order to prepare inexpensive hydrogen precipitation electrode catalysts with high efficiency in alkaline environment,five Co-Fe-Gd/NF electrode catalysts were prepared by electrodeposition in choline chloride-urea(ChCl-urea)with different deposition potentials.The electrode surface morphology,elemental content and distribution were characterized by SEM and EDX,and the chemical properties of the electrode surface were characterized by XPS.The combination of LSV,EIS and CV electrochemical test results showed that the Co-Fe-Gd/NF-3 electrode prepared at-1.24 V deposition potential possessed excellent hydrogen precipitation catalytic performance,with an overpotential of only 71 mV at 10 mA/cm^(2),a minimum Tafel slope(45 mV/dec).The smallest Tafel slope and charge transfer resistance(0.28503Ω/cm^(2))indicate that the electrode possesses a faster kinetic process for hydrogen precipitation reaction,and the maximum electrochemically active surface area(ECSA)is 390.5,which provides more reactive sites for the hydrogenation process.Cyclic voltammetric durability tset and I-t test were performed on the electrode,and the results showed that the Co-Fe-Gd/NF-3 electrode was stable in alkaline environments.