Electrochemical Properties of Graphene Paper Electrodes Used in Lithium Batteries

The electrochemical properties of graphene paper electrodes used in lithium batteries were reported. Scanning electron microscopy (SEM) studies of graphene paper show that it possesses a layered structure through the entire cross section. Cyclic voltammograms using graphene paper and graphite as electrodes in 1.0 M LiPF6 with Li as the counter and reference electrodes reveal a much higher specific cathodic current with graphene paper compared to graphite as the electrode. The strong, sharp peak at 1.47 V show that more active intercalation sites are available in graphene paper, which is found to be due to lithium interactions with the residual oxygen-containing functional groups within graphene nanosheets. Using the graphite electrode, the discharge capacity is found to be 298 mA h g-1, decreasing to 240 mA h g-1 after 50 cycles.