Abstract:

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.

Key words: Electrodeposition, Catalytic activity, Hydrogen evolution reaction, Nanocrystalline nickel alloy