Preparation of cobalt oxides nanoparticles modified exfoliated graphite for oxygen evolution reaction

In this study cobalt oxide nanoparticles were electrodeposited on the surface of exfoliated graphite graphenized as a low cost and efficient electrocatalyst for the OER [1-3]. The prepared cobalt oxide modified exfoliated graphite was carefully characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy and cyclic voltammetry techniques. The cobalt oxide modified exfoliated graphite exhibits excellent performance in electrocatalytic water oxidation in alkaline media due to synergistic effects arising from the exfoliated graphite and cobalt oxide nanoparticles. The prepared electrocatalyst represents low OER overpotential of 1.51V (vs. RHE) at the current density of 10 mA cm-2 and Tafel slope of 141 mV dec-1 in 1 M KOH solution. The cobalt oxide modified exfoliated graphite was highly stable and capable for maintaining catalytic activity for at least 4 h.