Facile synthesis of Co and Ce dual-doped Ni3S2 nanosheets on Ni foam for enhanced oxygen evolution reaction

Developing efficient and stable oxygen evolution reaction (OER) electrocatalysts via doping strategy has well-documented for electrochemical water splitting. Herein, a homogeneous structure (denoted as Co/Ce-Ni3S2/NF) composed of Co and Ce dual doped Ni3S2 nanosheets on nickel foam was synthesized by a facile one-step hydrothermal method. Co and Ce dopants are distributed inside the host sulfide, thereby raising the active sites and the electrical conductivity. Besides, the CeOx nanoparticles generated by part of the Ce dopants as a cocatalyst further improve the catalytic activity by adding defective sites and enhancing the electron transfer. As a consequence, the obtained Co/Ce-Ni3S2/NF electrode exhibits better electrocatalytic activity than single Co or Ce doped Ni3S2 and pure Ni3S2, with low overpotential (286 mV) at 20 mA-cm(-2), a small Tafel slope and excellent long-term durability in strong alkaline solution. These results presented here not only offer a novel platform for designing transition metal and lanthanide dual-doped catalysts, but also supply some guidelines for constructing catalysts in other catalytic applications.