电沉积纳米镍合金在海水溶液中的析氢性能

采用电沉积法获得Ni、Ni-Fe和Ni-Fe-C合金镀层电极, 在90 °C模拟海水(0.5 mol·L-1 NaCl, pH=12)的稳态极化曲线表明Ni-Fe-C合金电极具有最好的析氢催化性能. 通过扫描电子显微镜(SEM)观察电极表面形貌、X射线衍射(XRD)与透射电子显微镜(HRTEM)分析合金的晶体结构, 发现电极材料的晶粒尺寸影响析氢催化性能, 晶粒尺寸越小析氢催化活性越好. 用电化学阻抗方法(EIS)研究电极析氢催化性能的本质原因, 结果表明电极表面活性点数目和电极的本质电催化活性对合金电极析氢催化活性有重要的影响.

Electrodeposition of Nanocrystalline Nickel Alloys and Their Hydrogen Evolution in Simulated Seawater Solution

Ni, Ni-Fe, and Ni-Fe-C alloy electrodes were prepared by electrodeposition. Polarization curves showed that the Ni-Fe-C alloy electrode shows the best electrocatalytic activity for the hydrogen evolution reaction (HER) in a simulated seawater solution (0.5 mol·L-1NaCl, pH=12) at a temperature of 90 °C. The effect of morphology, composition and crystal structure on hydrogen evolution was studied by scanning electron microscope (SEM), X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM).We found that the grain size of the electrodes affect their electrocatalytic activity for the HER. A smaller grain size benefits the catalytic performance. Electrochemical impedance spectroscopy (EIS) indicated that an increase in active sites and intrinsic electrocatalytic activity is important for a major increase in the electrode catalytic activity for the HER.