FeNi-LDH@Ni film modified stainless-steel as self-supported electrodes for efficient and stable overall water splitting in alkaline environments

Abstract

Water electrolysis is a promising sustainable technology for hydrogen production. To achieve large-scale commercialization, electrocatalysts must meet specific performance requirements, such as low cost, high durability, and the ability for high-yield and high-quality production on a macroscopic scale. This study focuses on the preparation of self-supported electrodes for water splitting using stainless steel (SS) as the conductive carrier of the catalytic electrode. In alkaline conditions, FeNi-LDH@Ni films were grown on the surface of stainless steel, resulting in efficient and stable electrodes (FeNi-LDH@Ni/SS). The electrodes exhibited low overpotentials of 399 mV and 212 mV for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively, to reach a current density of 10 mA cm−2. Amplified electrodes with a surface area of 1 dm2 were tested in an industrial environment of 6 M KOH at 60 °C. The two-electrode alkaline water electrolyzers (AWE) composed of the two FeNi-LDH@Ni/SS electrodes demonstrated excellent stability for 100 h and required only 1.744 V to reach a current density of 10 mA cm−2. This study provides insight into the development of stable, efficient, and low-cost electrodes for industrial water splitting applications.