Recent advances in non-precious group metal-based catalysts for water electrolysis and beyond

As the demand for green hydrogen (H2) rapidly increases, the development of water electrolysis technology has been receiving great attention. Indeed, recent remarkable advances in catalyst materials increased the feasibility of water electrolysis for a future H2 economy and technology. In this review, we summarize representative non-precious group metal-based materials for achieving active and stable water electrolysis performances. Our comprehensive range of the state-of-the-art catalysts includes doped carbon catalysts, metal borides, metal carbides, metal oxides, metal phosphides, metal sulfides, and single-atom catalysts. For each class of materials, we focus on the synthesis and catalytic performances of the state-of-the-art materials toward water electrolysis and present the current challenges and outlooks of such materials, along with prospective insights to develop and realize practical systems.