Supercapacitor performances of thermally reduced graphene oxide

In this paper, graphene sheets with different reduction levels have been produced through thermal reduction of graphene oxide in the temperature range of 200–900 °C. The effects of interlayer spacing, oxygen content, BET specific surface area and disorder degree on their specific capacitance were explored systematically. The variation of oxygen-containing groups was shown to be a main factor influencing the EDL capacitor performances of the pyrolytic graphene. The highest capacitance of 260.5 F g−1 at a charge/discharge current density of 0.4 A g−1 was obtained for the sample thermally reduced at about 200 °C.

► Graphene with different reduction levels is produced through thermal reduction of GO. ► Oxygen content increases and interlayer spacing of pyrolysis GO decreases with temperature. ► Raising reduction temperature results in a lower ID/IG ratio and red-shift of G peak in Raman spectra. ► GO prepared at 200 °C delivers the highest specific capacitance of 260.5 F g−1. ► Oxygen content is shown to be a main factor influencing the EDL capacitor of pyrolysis graphene.