Our previous exciting results on graphene (G)-conducting polymer (polyaniline (PANI) and poly-ethylenedioxythiophene (PEDOT)) supercapacitors have prompted the investigation of G-substituted conducting polymer nanocomposites used as electrode materials in supercapacitors. The solubility of ortho-substituted PANI derivatives in a few common solvents has allowed the fabrication of stretchable films by the casting technique. The G-poly (o-anisidine) (G-POA) nanocomposites were synthesized with different weight ratios of G to o-anisidine by chemical methods, and characterized by various techniques, such as, scanning electron microscopy, transmission electron microscopy, UV visible spectroscopy, Raman spectroscopy, thermogravimetric analysis and cyclic voltammetry. The electrical conductivity and specific capacitance obtained for the G-POA nanocomposites were found to be dependent on the weight ratios of G to o-anisidine. The specific capacitance and the charging discharging behavior of the POA and G-POA supercapacitors were investigated in a 2 M H2SO4, 0.2 M LiCIO4 and 1 M 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM-PF6) ionic liquid. The specific capacitance of 380 F g(-1) was calculated for the 1:1 weight ratio of G to o-anisidine based G-POA supercapacitor in 2 M H2SO4. The presence of the electron-donating group (-OCH3) in the o-anisidine allows the electrons through the lone pair of nitrogen atoms to enhance the electronic charge transport inside the G-POA supercapacitor electrodes. However, the G-POA-based supercapacitors showed a 27% decrease in the specific capacitance in H2SO4 and 16% decrease in the ionic liquid (BMIM-PF6) after 1000 cycles of charging and discharging. The higher stability and rate capability of the G-POA based supercapacitor in an ionic liquid (BMIM-PF6) as compared to an aqueous electrolytic supercapacitor opens the door for the fabrication of stable supercapacitors for practical applications. (C) 2013 Elsevier B.V. All rights reserved.