Moreover, large polarization intensity of K + ions promote the higher charge density of electrical double layer compared to the acidic electrolyte as the warburg resistance of N-doped RGO in alkaline medium was found to be 1.26 Ω which is slightly lesser than acidic medium . In another work, Su et al. fabricated the N-doped graphene hydrogel (NGH) using hydrothermal processing of required amounts of vitamin C, carbamide into GO solution about 4 h at . Thus, the obtained NGH reached the gravimetric capacitance of 199.8 F g - 1 at 2 A g -1 in 6 M KOH solution which is relatively higher than the graphene hydrogel without N-doping (142. 23 F g -1 ) due to the appreciable content of nitrogen (8.97 at. %). Also, the SBET of NGH found to be 132.8 m 2 g -1 which is faintly higher than the graphene hydrogel in absence of nitrogen (122.9 m 2 g -1 ). Moreover, the NGH electrode displayed the 97% of capacitance retention after the completion of 20000 cycles.