Nickel and titanium metals for the hydrogen evolution reaction in water electrolysis: A comparative study

Abstract

This work investigated experimentally and theoretically the I-V output change, the hydrogen production, and the efficiency of Ti and Ni metals as substrates for water electrolysis systems. To make optimization between the candidate electrodes, seven configurations of Ni-Ti, Ti-Ti, and Ti-Ni with three KOH solutions of 10, 20, and 30 % wt (weight KOH gm/weight water gm) as an electrolyte were conducted as a cathode-anode system. The selected electrodes were examined by scanning electron microscopy (SEM) and energy dispersive (EDX) to study their surface morphology and element composition. According to experimental findings, when the cell voltage of 5 V is applied, the hydrogen production from the Ti-Ti (20%KOH) and Ni-Ti (20% and 30% KOH) electrodes reach an optimal value of 6331 cm3, which is significantly higher than the hydrogen production from the other electrodes at the same voltage. The Ni-Ti electrode with a 10% KOH content had the maximum efficiency (72%), and the Ni-Ti electrode with a 30% KOH content had the lowest efficiency (61%), both at 3V for the cell. This study demonstrates that the Ni-Ti system can be the most suitable source for hydrogen evolution rather than the other arrangements when the appropriate mixing ratio of 20 % KOH solution is prepared before the electrolysis process