Review of Catalytic Electrodes Containing Iron-Cobalt-Nickel Composite Components for Water Electrolysis.

Transition metal-based electrocatalytic materials for hydrogen production through water splitting offer advantages in terms of price and availability compared to noble metal-based catalysts, among which, Fe-, Co-, and Ni-based compounds are the most typical and widely studied materials. Utilizing the synergistic effects between composite components in compounds containing multiple metal elements is an important way to improve the catalytic performance of catalysts, so developing ternary or multiple active center catalysts containing Fe, Co, and Ni is a promising direction. In this mini-review, we provide an summary of the latest achievements of water splitting catalyst materials simultaneously containing Fe, Co, and Ni elements. It was summarized according to several groups including compounds of boron-/carbon-/nitrogen-/phosphorus-/oxygen-group elements, metal-organic framework-based compounds, and compounds in situ grown from alloy matrix. Also challenges that need to be addressed are presented at the end of the article.