Ni3S2@Co(OH)2 heterostructures grown on Ni foam as an efficient electrocatalyst for water oxidation

Abstract

It is of high significance to design robust, low-cost and stable electrocatalysts for the oxygen evolution reaction (OER) under alkaline medium. In this communication, we present the exploitation of Ni3S2@Co(OH)2 which directly grown on nickel foam (Ni3S2@Co(OH)2/NF) as a robust and stable electrocatalyst for OER. Such Ni3S2@Co(OH)2/NF-5h demanding overpotential of only 290 mV is less than that of Ni3S2@Co(OH)2/NF-10h (310 mV), Ni3S2@Co(OH)2/NF-2h (320 mV) and Ni3S2/NF(350 mV), respectively, to drive a geometrical catalytic current density of 35 mA cm−2, which is also better than that of noble metal catalyst IrO2/NF (320 mV). In addition, the Ni3S2@Co(OH)2/NF-5h presents a superior long-term electrocatalytic stability, keeping its activity at 26 mA cm−2 for 40 h.