Fe species-decorated nickel selenides on Ni foam (FNS/NF) for efficient overall water splitting

For industrial-scale green hydrogen production by water electrolysis, the catalyst used should exhibit the following characteristics: low cost, ease of use, high electrochemical activity, and good stability. In this study, we prepare a Pt replacement catalyst that can be used as an effective catalyst for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) as well as exhibits excellent stability. FeOOH-decorated nickel selenide on a Ni foam (FNS/NF), synthesized by decorating FeOOH on a NiSe/NF prepared by reacting an NF with a Se precursor under a hydrothermal condition, exhibited superior electrocatalytic activities in OER and HER. Furthermore, the (FNS/NF-5)||(FNS/NF-5) full-cell requires only 1.599 V to obtain 10 mA cm−2, demonstrating the utmost overall water splitting performance with convenience in a simple cell configuration.