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. IntroductionWith the rising progress of global economy and industry, the impending energy crisis has stimulated intense research on the low cost, environmentally friendly, and renewable energy resources. [ 1 ] Therefore, great efforts have been devoted to develop low cost electrode materials with high energy density, high power density, and excellent cycling stability. Supercapacitors, can be considered as the supreme candidate of the nextgeneration energy storage/conversion systems with the unique ability to store energy in a fraction of second and delivering the stored energy rapid enough than any other conventional energy storage devices. It also ensures high power density when coupled with batteries or fuel cells. [1][2][3][4] However, the supercapacitors suffer from low working potential that result in low energy density than conventional batteries. So, it's essential to improve their performances to encounter the higher requirements of future technologies by developing new materials with the interfaces at the nanoscale dimension. Lower specifi c energy of electrochemical double layer capacitors (EDLCs) with respect to the batteries and lower power densities of pseudocapacitors than EDLCs has motivated to develop the better performance characteristics hybrid supercapacitors. These hybrid supercapacitors use both Faradaic and non-Faradaic processes to store charge and thereby have achieved higher energy density and moderated power density accompanied with high cycling stability and thus have restricted the monopolism of pseudocapacitor.Intense research has established that combination of the micro structured carbonaceous materials with electroactive materials into a single system can take the benefi ts of both the double layer capacitance and pseudocapacitance arising from the synergistic interaction of the two. In this sense, graphene is the most interesting carbonaceous material with ultrahigh surface area (2600 m 2 g â1 ), excellent electric conductivity, two-dimensional sp 2 carbon arrangement with one-atom thickness. However, the strong electrostatic interaction amongst the graphene sheets leads to restacking of the sheets resulting in lower specifi c surface area and lower capacitance. [ 5 ] This drawbacks can be overcome by functionalization on the surface or incorporating nanocrystals in form of nanocomposites. The conducting polymers and transition metal oxides are two typical pseudocapacitive materials, which are capable of storing more charges than carbonaceous materials, but are limited by their poor stability and high resistance during cycling. The conducting polymer is frequently used into supercapacitor materials for obtaining the effi cient charge storage and delivery which strongly depends on the orientation of polymer chains into inorganic host. The polymer molecules are directed to grow along the large oriented tunnels of 3D hosts or interlayer space of the 2D hosts where the structurally organized frameworks are provided by the inorganic ...