Phosphate-Based Electrocatalysts for Water Splitting: Recent Progress

Efficient hydrogen production by water electrolysis is significant for the development of renewable energy. To date, the cost and scarcity of noble-metal catalysts are limiting their scale-up applications. To overcome the current challenge, high-performance novel electrocatalysts are required to speed up the commercialization of electrolysis technology. Notably, the sluggish electrode reactions, namely, the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), especially the latter, have been the main rate-limiting factor for water splitting. Phosphate, as a new series of OER electrocatalysts, has attracted enormous attentions, owing to its unique lattice structure geometry. The phosphate group not only benefits the adsorption of water molecule but also facilitates the oxyhydrate of metal site and dissociation of water. This Minireview provides a brief summary of the recent progresses of phosphate-based electrocatalysts, discusses the relationship between crystal structure and catalytic activity, and presents the challenges of phosphate electrocatalysts.