The Catalytic Effect of Hydroxide Layer on the Metal Surface in Alkaline Water Electrolysis

The production of hydrogen has been extensively studied since hydrogen is an ideal energy, high quality and clean energy carrier. Currently, the hydrogen is mainly produced by the fossil fuels or other carbon-based fuels. However, the production technology of hydrogen via the fossil fuels causes global warming by emitting environmental pollutions such as CO, CO2, and CH4. Thus, a lot of efforts have been dedicated to the production of hydrogen through the clean renewable energy sources such as water, biomass. Among these technologies, an alkaline water electrolysis has been considered as the promising candidate for the green hydrogen technology. The high catalytic activity and durability of the electrodes should be guaranteed for commercialization of alkaline water electrolysis. Platinum group metals are renowned for their exceptional catalytic activity in alkaline water electrolysis. However, their widespread commercial adoption is hindered by the substantial costs involved and their tendency to dissolve during the oxygen evolution reaction (OER). For this reason, catalysts from the hydroxide family, such as NiFe LDH, currently dominate the field of OER catalysis. This paper introduces a novel technique: hydrating metal substrates to significantly enhance OER efficiency. Utilizing a straightforward hydration, the hydroxide layer with a thickness of only a few nanometers can be developed on the Ni surface.The ability to significantly enhance OER performance through the simple hydration of metals suggests a promising strategy for the development of new electrocatalysts.