- In this work we present a nanostructured nickel-based electrode with high surface area as cathode for the hydrogen evolution (HER) during alkaline water electrolysis (AEL). The electrodes are prepared via mechanical plating of aluminum on a nickel sheet and thermal treatment in N2-atmosphere at different temperatures to achieve leachable NiAl-phases such as Ni2Al3 and NiAl3. Focus is to increase the electrochemical surface area (ECSA) significantly. The electrochemical performance is evaluated with cyclic voltammetry (CV) and chronopotentiometry (CP) in a three-electrode and full cell setup at current densities up to 1 A/cm2. High efficiency values at the cathode with Tafel slopes from 70 to 80 mV/dec and low overpotentials of 170–200 mV at high currents are determined. Electrochemical impedance spectroscopy (EIS) and chronopotentiometry (CP) are used to study resistances, degradation and stability of the fabricated electrodes. The “carpet-like” structure of the electrode leads to aIn this work we present a nanostructured nickel-based electrode with high surface area as cathode for the hydrogen evolution (HER) during alkaline water electrolysis (AEL). The electrodes are prepared via mechanical plating of aluminum on a nickel sheet and thermal treatment in N2-atmosphere at different temperatures to achieve leachable NiAl-phases such as Ni2Al3 and NiAl3. Focus is to increase the electrochemical surface area (ECSA) significantly. The electrochemical performance is evaluated with cyclic voltammetry (CV) and chronopotentiometry (CP) in a three-electrode and full cell setup at current densities up to 1 A/cm2. High efficiency values at the cathode with Tafel slopes from 70 to 80 mV/dec and low overpotentials of 170–200 mV at high currents are determined. Electrochemical impedance spectroscopy (EIS) and chronopotentiometry (CP) are used to study resistances, degradation and stability of the fabricated electrodes. The “carpet-like” structure of the electrode leads to a 4200x increased surface area of the Nickel catalyst with optimized gas desorption and transport of hydrogen.…
