Symmetric supercapacitor based on partially exfoliated and reduced graphite oxide in neutral aqueous electrolyte

• Partially exfoliated and reduced graphite oxide has been synthesized by a simple thermal heat treatment.
• A symmetric carbon/carbon supercapacitor is studied in a Na2SO4 aqueous electrolyte.
• The symmetric system demonstrate a stable charge/discharge cycle behavior up to 3000 cycles when the cell is operated at a voltage window of 1.6 V.

The partially exfoliated and reduced graphite oxide (PE-RGO) is prepared by low temperature thermal exfoliation of graphite oxide under air atmosphere. A symmetric carbon/carbon supercapacitor is studied in a Na2SO4 aqueous electrolyte. The discharge capacitance is 92 F g−1, when symmetric cell is cycled between the potential ranges from 0 to 1.6 V. This system demonstrates a stable charge/discharge cycle behavior up to 3000 cycles when the cell is operated at a voltage window of 1.6 V. The utilization ratio of potential window is 90% for this system is attributed to the more negative value of electrodes potential when the cell voltage is set to 0 V. The low-temperature exfoliation approach is convenient for mass production of graphenes at low cost and it can be used as electrode material for energy storage applications.