Electrocatalytic Activity of Nickel-Cerium Alloys for Hydrogen Evolution in Alkaline Water Electrolysis

Nickel-cerium (Ni-Ce) alloys of different compositions were fabricated and evaluated as electrodes for hydrogen evolution reaction (HER) in alkaline media. HER at Ni-Ce electrodes was studied in 8 M KOH solution for temperatures ranging from 25 to 85 degrees C. Polarization curves were recorded using both Ni-Ce alloys and pure Ni electrode, and further analyzed enabling determination of main kinetic parameters. The parameters determined, namely Tafel coefficients, charge transfer coefficients, exchange current densities and activation energies, made possible a direct comparison of the studied electrodes performances for the HER. It was observed that low amounts of Ce in the alloys did not result in significant improvement of the catalytic activity of the Ni-based electrodes. Nevertheless, the present results are encouraging and support further investigation to determine the optimal composition of Ni-Ce alloys for hydrogen evolution. (C) 2014 The Electrochemical Society. All rights reserved.