Fabrication of 1.6 V asymmetric supercapacitor in an aqueous electrolyte using a CuO-SnO2 composite and activated carbon electrodes

Abstract

This work reported the successful preparation of the CuO and SnO2 by the facile co-precipitation method for energy storage applications, especially for supercapacitors (SCs). Subsequently, a CuO-SnO2 composite was further prepared to enhance the composites electrochemical properties. The detailed research survey showed that the combination of these two typical pseudocapacitive metal oxides reasonably enhances their structural integrity, and electronic conductivity, resulting in an optimized electrochemical property. According to the electrochemical studies, an exceptional 246 C/g capacitance is revealed by the CuO-SnO2 composite than 162 C/g (SnO2) and 89 C/g (CuO) exhibiting a synergistic effect in the composite between Sn and Cu-based oxides. A high specific energy of 35.3 Wh/kg with a maximal specific power of 4000 W/kg was obtained by assembling a hybrid asymmetric SC (HASC) with activated carbon (AC), symbolized as CuO-SnO2||AC, that yields a high voltage of 1.6 V. Nevertheless, 88.7 % retention in capacitance was revealed after 5000 cycles taken at a the discharge current of 15 A/g, proving the great durability of the CuO-SnO2||AC HASC. From all these exciting findings, SnO2 composite with CuO can be a potential and a viable choice for SCs and other energy storage gadgets.