Comparison of Electrochemical Properties of Ni+NiAl and Ni Coatings in an Alkaline Solution

Abstract

The Ni+NiAl nanocomposite coatings were prepared by the electrodeposition under the galvanostatic conditions (jdep= -250 mA cm-2) from the nickel bath containing the suspension of NiAl nanopowder. For comparison, the Ni coatings were also obtained. The combined steady-state polarization and electrochemical impedance spectroscopy (EIS) investigations of hydrogen evolution reaction (HER) were carried out in 5 M KOH solution at room temperature. It was found that the Ni+NiAl nanocomposite coatings revealed higher apparent electrocataltic activity towards the HER as compared to the comparable Ni deposits due to the increase in the real surface area development and the intrinsic activity.