Reduced graphene oxide composite Ni3S2 microspheres grown directly on nickel foam as an efficient electrocatalyst for OER

Abstract

The development of cheap, high-efficiency, and stable oxygen evolution reaction (OER) electrocatalysts is a current research hotspot. In this work, reduced graphene oxide (rGO) composite Ni 3 S 2 microspheres grown directly on nickel foam (Ni 3 S 2 -rGO/NF) were prepared by tube furnace calcination and hydrothermal method . The Ni 3 S 2 -rGO/NF had excellent OER catalytic activity and stability with an overpotential of 303 mV at the current density of 100 mA cm −2 , which was 100 mV lower than that of Ni 3 S 2 /NF, and its Tafel slope was as low as 23 mV·dec −1 . The main reason for enhancing OER activity of the Ni 3 S 2 -rGO/NF is due to synergistic effect of Ni 3 S 2 microspheres and rGO, which inhibited the production of NiS and refined the micron size of Ni 3 S 2 . This work offers a new method for developing stable and efficient OER catalysts.