Reduced graphene oxide: a promising electrode material for oxygen electrodes

A method for the chemical synthesis of reduced graphene oxide has been developed. It is based on the chemical oxidation of multiwalled carbon nanotubes by means of heptavalent manganese with subsequent reduction. Sodium hypophosphite and sulfite were used as reductants. It has been confirmed by different methods that reduced graphene oxide is obtained. Current-potential curves for electrodes based on reduced graphene oxide in an oxygen fuel cell mock-up with alkaline electrolyte have been studied. It has been found that the characteristics of the electrode of graphene oxide reduced with sodium hypophosphite in oxygen reduction reaction are three to four times higher than those of the electrode of starting multiwalled carbon nanotubes. The electrodes based on reduced graphene oxide are superior to multiwalled carbon nanotube-MnO2 composite in characteristics. The characteristics of oxygen electrodes based on reduced graphene oxide were stable during 6-month tests. The reduced graphene oxide obtained promises much as a material for the oxygen electrodes of electrochemical power sources.