respectively. The group also assembled a symmetric supercapacitor using PG-C, which delivered an energy density of 9.38 W h Kg -1 at the power density of 375 W Kg -1 in 6 M KOH electrolyte. Further, it is to be noted that, the HTC-PG-C, PG-AC, HTC-PG-AC, and HRC-NPG-AC assembled supercapacitors showed the high energy density of .84 W h Kg -1 at 400 W Kg -1 , respectively. Further, the PG-C, HTC-PG-C, PG-AC, HTC-PG-AC, and HTC-NPG-AC symmetric supercapacitor were assembled using 1 M Na2SO4 as electrolyte, which were capable of delivering the energy densities of .56 W h Kg -1 at 500 W Kg -1 , respectively. Numerous studies have reported the high capacitive and energy-density behaviour of carbon-based materials with ultra-thin electrodes, or active materials with low mass loading (< 1 mg cm -2 ). However, the low-mass loading of active materials often leads to poor capacitances based on area of the device, and ultimately leads to poor energy performances.