In-situ developed carbon spheres function as promising support for enhanced activity of cobalt oxide in oxygen evolution reaction.

Highly active, stable electrocatalyst for oxygen evolution reaction (OER) is sincerely required for the practical application of water splitting to get rid from the sluggish reaction kinetics and the stability issue. Here, CoO is studied as OER catalyst and to improve the electrocatalytic activity, carbon is chosen as the conducting support. A simple and cost-effective synthetic route is developed for the synthesis of CoO on carbon support following hydrothermal route using various hydrolyzing agents. The heterostructure 'CoO/C' perform well in OER as a non-precious metal catalyst. The best CoO/C electrocatalyst can generate 10 and 30 mA/cm current densities upon application of 1.623 V and 1.678 V vs. RHE whereas, bare CoO can generate current density of 10 and 30 mA/cm upon application of 1.677 and 1.754 V vs. RHE. Carbon in the heterostructure helps to improve the conductivity and at the same time enhances the charge transfer ability which further leads to increase current density and stability to the catalyst. CoO/C can generate unaltered current density up to 1000 cycles.