Recently, the preparation of heteroatom doped graphene by supercritical water was explored in the literature. Suresh Balaji et al. investigated the S-doped graphene as a symmetric supercapacitor in aqueous, non-aqueous and ionic liquid-based electrolytes . The S-doped graphene was synthesized by mixing the GO solution with dimethyl sulfoxide (DMSO) in different weight ratios under supercritical water as a solvent at 400 °C for 1 h. Also, the electrochemical capacitance of S-doped graphene prepared under supercritical method using two different S-precursors were compared. Among the three different weight ratios, the Sdoped graphene in which DMSO and GO are in the weight ratio 1:2 displayed the specific capacitance of 261 F g -1 in 20% KOH solution at 1 A g -1 which is greater than RGO (170 F g - ) and thioacetamide based S-doped graphene (198 F g -1 ) and the appropriate CV and CD profiles are displayed in Fig. and The S-doped graphene attained a specific capacitance of 47 F g -1 at 1 mA cm -2 in 1 M TEABF4/PC electrolyte which is faintly higher than desulfurized graphene (37 F g -1 ).