High Density and Unit Activity Integrated in Amorphous Catalysts for Electrochemical Water Splitting

Electrochemical water splitting is regarded as a most effective hydrogen production technique. In fact, quite a few exceptional electrocatalysts, processes, and even large‐scale demonstrations have been developed. In particular, some amorphous catalysts have become well‐known for their extraordinary performance on account of their disordered structure, numerous, uniformly distributed active sites with high unit activity and better stability that outshine their single‐crystalline counterparts. Herein, a review of recent research advances of amorphous catalysts used in electrocatalytic water splitting are provided, including both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Particularly, the scaled‐up application of amorphous catalysts with multifarious compositions and diverse heterostructures in electrolyzing water and the reason why amorphous catalysts exhibit excellent catalytic performance are emphasized on. In addition, the mechanism of water electrolysis and the evaluation criteria of catalytic properties are analyzed in detail. Finally, the broader development outlook of amorphous catalysts is discussed.