Phosphorus-doped nickel sulfides/nickel foam as electrode materials for electrocatalytic water splitting

Hydrogen production from electrocatalytic water splitting is viewed as one of the most promising methods to generate the clean energy. In this work, we successfully prepared an electrode material by growing phosphorus-doped Ni3S2 (PNi3S2) on nickel foam substrate (NF) under hydrothermal conditions. The phosphorus-doping has an obvious effect on the morphology of Ni3S2 on the surface of the nickel foam, which probably results in more active sites, higher electrical conductivity and faster mass transfer. The resulting electrode material displays excellent electrocatalytic activities and stability towards both OER (oxygen evolution reaction) and HER (hydrogen evolution reaction). A relatively low overpotential of 306 mV is required to reach the current density of 100 mA cm−2 for OER and 137 mV at 10 mA cm−2 for HER in 1 M KOH solution. When PNi3S2/NF was used in an electrolyzer for full water splitting, it can generate a current density of 10 mA cm−2 at 1.47 V with excellent stability for more than 20 h.