(i) low surface area, (ii) low conductivity and (iii) low capacitance. In the case of pristine graphene, the decrease in ion-accessible surface area critically limits the accumulation of charge carries and the formation of electrical double layer (EDL). From the perspective of condensed matter physics, fabrication of graphene with sp 2 bonded carbon atoms could be obtained through hybridization of s, px, and py atomic orbitals, and resulting in 3 strong s bonds with 3 adjoining atoms . The valence band and conduction band are created by the fourth orbital (pz), presented on every carbon atom by interacting with nearest atoms. Thus, with the absence of a substantial band gap, graphene may be looked upon as a metal with evaporating Fermi surface or a semiconductor, and due to which the applications of pristine graphene have been restricted to a large extent in electrocatalysis, energy storage, nanoelectronics, and sensing.