摘要
采用快速凝固结合脱合金化方法制备了不同Mo含量的纳米多孔Ni-Mo合金,通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和N 2吸附-脱附分析等对多孔合金的物相、形貌结构及孔径分布进行了表征,并通过线性扫描伏安、Tafel斜率、交流阻抗和循环伏安等方法测试了多孔合金电极的电催化析氢性能.结果显示,多孔合金电极材料在50 mA/cm^2电流密度下析氢过电位随着Mo含量的增加先降低后升高,Ni 2.5 Mo 2.5合金析氢活性最强,过电位为218 mV,析氢过程由Volmer-Heyrovsky步骤控制,交换电流密度为0.29 mA/cm^2,经1000周循环后的极化曲线基本保持原状,50 mA/cm 2电流密度下过电位增加3.67%,表现出优良的析氢稳定性.
Nanoporous Ni-Mo alloys with different Mo contents were prepared by rapid solidification and dealloying. The phase, morphology and pore size distribution of porous electrode materials were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and N 2 adsorption-desorption analysis. The electrocatalytic hydrogen evolution of porous electrode was tested by linear sweep voltammetry, Tafel slope, alternate current impedance and cyclic voltammetry. The results show that the hydrogen evolution overpotential of the prepared porous electrode material decreases first and then increases with the increase of Mo content at a current density of 50 mA/cm ^2 . The hydrogen evolution activity of Ni 2.5 Mo 2.5 alloy is the highest, and the hydrogen evolution process on it is controlled by Volmer-Heyrovsky step. The apparent exchange current density of Ni 2.5 Mo 2.5 alloy electrode is 0.29 mA/cm ^2 . After 1000 cycles of cyclic voltammetry, the polarization curve remains basically the same, and over potential increased only by 3.67% under a current density of 50 mA/cm 2 , showing excellent hydrogen evolution stability.
作者
周琦
李志洋
汪帆
ZHOU Qi;LI Zhiyang;WANG Fan(State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals,College of Materials and Engineering,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2019年第8期1717-1725,共9页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:51661018)资助~~
关键词
快速凝固
脱合金化
多孔Ni-Mo合金
电催化析氢
Rapid quenching
De-alloying
Porous Ni-Mo alloy
Electrocatalytic hydrogen evolution
