Nitrogen-doped porous graphitized carbon (N-F-PREGO) were synthesized by doping the fluorinated porous graphitized carbon with ammonia gas at reaction temperatures of 400-850 degrees C. In N-F-PREGO synthesized at 400 degrees C, nitrogen atoms were introduced into the porous graphene framework at a concentration of 7.9 at.%. Among which, the concentrations of the pyridinic-, pyrrolic-, and graphitic-type nitrogen species were 5.14, 1.78, and 0.99 at.%, respectively, and their percentages with respect to the total nitrogen species were 65.0, 22.5, and 12.5%, respectively. Meanwhile, the original specific surface area of 2022 m(2)/g and abundant meso- and microporous were well-preserved after doping process. Herein, the specific capacitance of the nitrogen-doped PREGOs was improved from 103 F/g to 294.2 F/g at a current density of 1.0 A/g. At 10 A/g, the specific capacitance was reserved at 272.5 F/g, and well retained even after 10,000 cycles at 5 A/g.