Fabrication of Efficient Electrocatalysts for Electrochemical Water Oxidation Using Bimetallic Oxides System

The study focused on the fabrication of nickel, cobalt, and their bimetallic oxide via a facile electrodeposition approach over the surface of conducting glass has been reported here. Fabricated electrodes have been employed as binder-free and effective anode materials toward oxygen evolution reactions (OER) in electrochemical water splitting at high pH. Nickel and cobalt oxides showed overpotential values of 520 mV and 536 mV at the current density of 10 mAcm^-2 with charge transfer resistances of 170 and 195 Ω. For bimetallic oxides (NiCoO@FTO), the overpotential depressed up to 460 mV and lower charge transfer value of 80 Ω. Additionally, double-layer capacitance also boosted for the bimetallic oxide with a value of 199 μF as compared to monometallic nickel oxide (106 μF) and cobalt oxide (120 μF). Multimetal oxides of Ni-Co showed the best performance, which was further supported with larger electrochemical surface area. This facile approach toward the electrode fabrication could be a charming alternate to replace the Ru- and Ir-based expensive materials for OER in electrochemical water splitting.