NiO/Co 2 P Nanosheets with Heterogeneous Structure as a Multifunctional Catalyst for Overall Water Splitting

Abstract

Exploring efficient and low-cost multifunctional electrocatalysts is a prerequisite for the development of energy storage and converting technology. In this work, NiO/Co 2 P nanosheets (NiO/Co 2 P NSs) with heterogeneous structure were investigated through hydrothermal method, annealing and phosphating processes. Considering the synergistic effect between NiO and Co 2 P, we demonstrated the excellent electrocatalytic properties of NiO/Co 2 P NSs for OER and HER. By optimizing the electronic structure of NiO and Co 2 P, as well as the high specific surface area of the nanosheet structure and the presence of a large number of mesopores, more active sites are exposed and the electrocatalytic efficiency is improved, thus providing excellent electrocatalytic performance. Specifically, NiO/Co 2 P NSs can reach 108 and 207 mV at the current density of 10 mA cm −2 in alkaline medium for HER and OER. And it requires a voltage of 1.57 V to reach a current density of 10 mA cm −2 for overall water splitting. In conclusion, this study demonstrates the critical contribution of heterogeneous structures to promote electrocatalytic properties and open new perspectives for designing multifunctional catalysts.