A novel synthesis strategy for hybrid quaternary rGO/MnO2/NiO/CuO nanocomposite as electrode for enduring symmetric supercapacitor fabrication

Abstract

Supercapacitors are one of the emerging energy devices due to the evolution in modern technologies which involve fast charging mechanisms with long-lasting stability and good retentivity. A hybrid quaternary composite of transition metal oxide consisting of MnO2, NiO, CuO nanospheres and reduced graphene oxide (rGO) was synthesized by a fusion method with enhanced supercapacitive behaviour. This nanocomposite was subjected to various structural, functional, morphological and electrochemical characterizations and further fabricated into a symmetric supercapacitor with benefiting and facile design. The electrochemical studies were carried out under electrolytes with different pH and mole concentrations both under 3-electrode and 2-electrode systems. The highest specific capacitance of 816.51 F/g was obtained with energy and power densities of 72.57 W h/kg and 0.5 kW/kg. The highest power density of 2.5 kW/kg was achieved corresponding to the current density of 5 A/g. Excellent cyclic retention of 86.46% was achieved after 5000 cycles proving long-term cyclic stability under 1 M KOH. Unfolding the nanocomposite to be a virtuous reference for supercapacitors’ future.