Impact of morphological variation by phase-oriented MnO2-based hierarchical ternary composites for the fabrication of solid-state symmetric supercapacitor

摘要

In this study, we claimed a two-step strategy to prepare an inexpensive carbon sphere (CS) from sugarcane bagasse followed by polypyrrole (PPy) incorporation to obtain CPP (CS/PPy) nanocomposites. Subsequently, various phase-oriented MnO2 nanostructures have been introduced at CPP to obtain ternary hybrid CS/PPy/MnO2 (CPPM-1, CPPM-2, and CPPM-3) nanocomposites with ease. CPPM-1 nanocomposite-loaded electrode exhibits high capacitance of 1052.5 F/g at 0.5 A/g current density in three-electrode system. Many efforts have been devoted to develop a unique solid-state symmetric supercapacitor using CPPM-1 nanocomposites separated by solid electrolytic film (PVA-H2SO4) which shows a rapid charging and slow discharging in 60 s and 240 s, respectively. An excellent energy density of 10.4 Wh/kg was maintained at power density of 2000 W/kg in the current density of 5 A/g along with high cyclic stability as capacitance retention up to 92.3% after 5000 cycles at CPPM-1-based solid-state symmetric supercapacitor.