This book discusses modified copolymers synthesized with styrene maleic anhydride and dimethyl diphenylmethane, incorporating GO/ZnO nanocomposite. The electrochemical performance of the nanocomposite exhibited a specific capacitance of 514 F g-1 at a current density of 0.4 Ag-1 and capacitive retention of 75-76% cyclic stability after 1000 cycles. The functionalization enhanced the conductivity of polymer nanocomposite, resulting in a high-performance energy storage application.