Electrochemical hydrogen production of SS, Ni, and Ni-B electrodes in prototype electrolyzer system

Abstract

Highly efficient, low-cost, and stable electrocatalysts are crucial in electrocatalytic water splitting. Herein, the comparative study of stainless steel (SS), a Nickel (Ni/SS), and Nickel boride (Ni-B/SS) electrode for hydrogen production was carried out under a prototype electrolyzer system. The Ni/SS and Ni-B/SS were synthesized by a simple and low-cost chemical method on the SS substrate. As compared to SS and Ni/SS electrodes, the Ni-B/SS electrode demonstrates superior electrochemical activity towards the Hydrogen Evolution reaction (HER) with a low overpotential of 75 mV at a current density of 10 mA/cm2 and Tafel slope of 82 mV/dec in 1M KOH electrolyte. The as-fabricated Ni-B/SS electrode showed cauliflower-like morphology and exhibited an excellent hydrogen production rate such as 4.39 ml/min on a (2 cm x 2 cm) electrode at a constant potential of 2.2 V in a prototype electrochemical hydrogen production setup. The stability of the Ni-B/SS (6 cm x 6 cm) electrode was also checked on a large-scale prototype electrolyzer setup for 50 hr at a constant potential.