<p>Due to the recent surge in the development of novel energy storage technologies, unique compositions have emerged which aim to broaden this field of study. Our earlier investigations have depicted the electrochemical performances of thiadiazole and diamine modified poly (styrene-co-maleic anhydride) and their nanocomposites for efficient energy storage devices. Here, we aim to improve this scaffold further through the incorporation of Graphene oxide (GO) and Zinc oxide (ZnO) nanoparticles to the polymer matrix of poly (styrene-co-maleic anhydride). GO and ZnO NPs impart synergistic effects of both pseudocapacitance and electrical double layer capacitance to the resultant nanocomposite. These samples have been characterized extensively to substantiate their spectral, morphological and thermal properties. Additionally, they have been subjected to electrochemical testing to evaluate their supercapacitive performance. The developed supercapacitor electrodes exhibit a high specific capacitance of 850 Fg^− 1 at 5 mV s⁻¹ coupled with a capacitance retention of 93% after 1000 cycles at 1&#xa0;A g^− 1. Based on these attributes, the prepared nanocomposites exhibited great potential to be considered as potential alternatives to conventional supercapacitors.</p>