Co/CoP@NC heterostructures as bifunctional catalysts to enhance the alkaline water splitting

The development of efficient and stable non-precious bifunctional electrocatalysts is of great significance, but it remains a great challenge. Herein, we have constructed Co/CoP@NC heterojunction catalyst loaded with Co and CoP particles on a nitrogen-doped carbon (NC) substrate using the pyrolysis-oxidation-phosphating strategy. The synergistic effect of Co and CoP particles on the NC substrate increases the active specific surface area, accelerates the charge transfer rate, and improves the intrinsic activities of the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The Co/CoP@NC catalyst exhibits superior HER and OER performance. Specifically, the overpotentials required for Co/CoP@NC to reach the current density of 10 mA cm- 2 are 142 and 186 mV for HER and OER, respectively. This study provides new insights into the design and synthesis of efficient and stable Co-based heterostructure catalysts.