Recent progress in CoP-based materials for electrochemical water splitting

Over the past years, transition metal phosphides (TMPs)-based materials have attracted extensive attention as noble-metal-free electrocatalysts for hydrogen evolution reactions and oxygen evolution reactions because of their high conductivity, high electrocatalytic activity, and stability. As a typical TMP, CoP-based materials are widely adopted as electrocatalysts in electrochemical water splitting owing to their unique physical properties, such as a P-rich component and superior charge transferability. Very recently, the research efforts focus on using various effective strategies to further enhance the electrocatalytic performance of CoP-based catalysts. However, no guideline for systematically improving their electrocatalytic activity exists currently. Hence, this review summarizes recent advances in optimizing the electrocatalytic performance of CoP-based materials from four aspects, namely, morphology design, construction of heterointerface, defect engineering, and atomic doping. Finally, this study briefly proposes the existing challenges and the future working directions for designing advanced CoP-based electrocatalysts and other non-previous metal electrocatalysts.