One-step plasma electrochemical synthesis and oxygen electrocatalysis of nanocomposite of few-layer graphene structures with cobalt oxides

Abstract One-step synthesis of the nanocomposite of few-layer graphene structures with cobalt oxides was realized using the method of electrochemical exfoliation of graphite. The exfoliation process was carried out in alternating anodic-cathodic plasma mode in 1 М Na2SO4 + 0.01 M CoSO4 solution. Obtained nanocomposite was characterized by scanning and transmission electron microscopy, X-ray photoelectron and Raman spectroscopy. Besides, a catalytic activity of the nanocomposite of few-layer graphene structures with cobalt oxides towards the oxygen reduction reaction was assessed, and a considerable decrease in the oxygen reduction overpotential and an electron transfer number of ca. 3.6 were demonstrated. The observed effect was found to be caused by 40 wt.% of cobalt (II) and (III) oxides in the nanocomposite.