Design, Fabrication, and Characterization of Graphitic Carbon Nitride Nanosheets as Supercapacitors Electrode

This work reports the successful design, fabrication and characterization of graphitic carbon nitride (g-C3N4) nanosheets as electrode materials for supercapacitors (SCs). Herein, g-C3N4was synthesized with the facile thermal polymerization method and the electrochemical stability of the as-prepared g-C3N4electrode was analyzed considering three different aqueous electrolytes 1 M Na2SO4(neutral), 6 M KOH (alkaline), and 1 M H2SO4 (acidic). The best specific capacitance of g-C3N4was obtained in an acidic medium (188.65 F/g) compared to alkaline (145.75 F/g) and neutral electrolyte (110.92 F/g) at a current density of 1 A/g. After 2000 charge-discharge cycles, capacity retentions of 70.53%, 73.98%, and 74.44% were achieved with neutral, alkaline, and acidic mediums, respectively. However, the energy density of 26.3 Wh/kg, 20.25 Wh/kg, and 15.5 Wh/kg were observed whereas the maximum power density obtained as 2.491 kW/kg, 2.486 kW/kg, and 2.482 kW/kg using acidic, alkaline, and neutral electrolytes respectively. Therefore, this study evaluates the potential of g-C3N4as the efficient base material for the fabrication of a variety of SCs composed of materials having different electrochemical stabilities for variety of application including portable and flexible energy storage devices.