Featherlike NiCoP Holey Nanoarrys for Efficient and Stable Seawater Splitting

Developing earth-rich highly efficient nonprecious electrocatalysts for hydrogen evolution reaction (HER) has become of great significance for sustainable energy technology. Herein, novel nickel foam (NF) supported porous featherlike NiCoP (PF-NiCoP/NF) nanoarrys are constructed by a successive hydrothermal and phosphidation way. Simultaneously, their three-dimensional (3D) morphology, the holey structure, and the conductive substrate are favorable for the enhanced specific surface area, efficient electron and mass transfer, and exposure of more active sites, and also are beneficial for the release of generated H2. PF-NiCoP/NF demonstrates high activity and long-term durability in alkaline media (1 M KOH) and real seawater, reaching the current density of 10 mA cm–2 at overpotentials of 46 and 287 mV, respectively. Moreover, the faradaic efficiency of 3D PF-NiCoP/NF is as high as 96.5% in real seawater. As expected, PF-NiCoP/NF exhibits superior performance in comparison to those of most of HER electrocatalysts in real seawater and alkaline media. This work may present a new strategy to design a promising electrocatalyst superior to platinum in a wide range of pH and may provide a new idea for electrocatalytic seawater splitting.