氯化胆碱-乙二醇深共熔体系电沉积Ni-Mo合金镀层动力学及其电催化析氢性能

Electrodeposition kinetics of Ni-Mo alloy coating in choline-ethylene glycol deep eutectic system and its catalytic performance toward hydrogen evolution reaction

以Cu片为基体,在氯化胆碱-乙二醇深共熔体系中电沉积制备Ni-Mo合金镀层,借助EIS,SEM,EDS和XRD等手段分析Ni-Mo合金镀层沉积动力学,探讨极化电位对Ni-Mo合金镀层电催化析氢性能的影响规律。结果表明:随着极化电位的增加,Ni-Mo合金镀层经历从纳米Ni,Ni+MoO_(2)(MoO_(2)Ni_(4))和Ni_(4)Mo成分演变过程,说明电位驱动是影响Ni-Mo合金镀层成分变化的重要原因。当极化电位为-1.4 V vs Ag时,Ni-Mo-1.4合金镀层具有优良的析氢催化活性和催化稳定性,其在10 mA·cm^(-2)电流密度下的析氢过电位仅为51 mV,Tafel斜率为48.7 mV·dec^(-1),循环催化1000周次后在100 mA·cm^(-2)电流密度下的析氢过电位下降较小(Δη100=11 mV)。

The Ni-Mo alloy coatings were electrodeposited in the choline-ethylene glycol deep eutectic system(ChCl-EG)using Cu as the substrates,and the electrochemical impedance spectrum(EIS),scanning electronic microscopy(SEM),energy dispersive spectrometer(EDS)and X-ray diffraction(XRD)were employed to investigate the deposition kinetics of Ni-Mo alloy coatings.The influence of polarization potential on electrocatalytic HER performance of Ni-Mo alloy coatings was investigated.The results indicate that as the polarization potential increases,the Ni-Mo alloy coatings undergoes a process of evolution from nano Ni,Ni+MoO_(2)(MoO_(2)Ni_(4))to Ni_(4)Mo,indicating that potential is an important factor affecting the component change of Ni-Mo alloy coatings.Ni-Mo alloy coating fabricated at-1.4 V vs Ag displays excellent hydrogen evolution catalytic activity and stability,where the overpotential at 10 mA·cm^(-2)is only 51 mV,the Tafel slope is 48.7 mV·dec-1,and the decrease in hydrogen evolution overpotential is not significant(Δη100=11 mV)at 100 mA·cm^(-2)after 1000 cycles of catalytic cycling.