Physical activation assisted porous activated carbon from Strychnos Potatorum shells for high-performance symmetric supercapacitors

Abstract

Herein, low-cost activated carbon (AC) prepared from Strychnos Potatorum shells using CO2 as an activating agent via physical activation technique. Waste biomass-derived AC have the merits of excellent conductivity and highly porous with high-surface area. Electrochemical assessments indicated that the prepared Strychnos Potatorum derived activated carbon (SPAC) electrode exhibited superior electrochemical performance. The experimental data showed that the specific capacitance of 352.5 F g−1 at 0.5 A g−1 and retained 140 F g−1 at 20 A g−1. Symmetric supercapacitors SPAC//SPAC device displayed an impressive specific capacitance of 147 F g−1 at 0.1 A g−1 and an energy density of 20.41 W h kg−1 at 100 W kg−1 and retained 2.7 Wh kg−1 at 10000 W kg−1. Furthermore, these supercapacitors demonstrated exceptional cyclability, maintaining capacity retention of 92.3 % over 10,000 charge–discharge cycles at 1 A g−1. This research work underscores the promising potential of AC materials derived from Strychnos Potatorum shells in development of high-performance supercapacitors.