Nanocomposites of nitrogen-doped graphene and cobalt tungsten oxide as efficient electrode materials for application in electrochemical devices

Nitrogen-doped graphene (N-GNS), cobalt tungsten oxide (CoWO₄) and their binary composites have been synthesized and their structural and electrochemical and surface properties were investigated for application as electrode materials for oxygen reduction reaction (ORR) as well as super capacitors in 1 M KOH at 25 °C. Result shows that the composite, 40%CoWO₄/N-GNS, has greatly enhanced capacitance as well as retention capacity, compared to its constituent compounds, N-GNS and CoWO₄. The ORR activity and stability of the composite are also found to be much superior to N-GNS (or CoWO₄) under similar conditions. The 40%CoWO₄/N-GNS catalyst has also exhibited reasonably good catalytic activity for oxygen evolution reaction (OER) while that the N-GNS electrode was practically inactive.