Momordica Charantia pericarp derived activated carbon with dual redox additive electrolyte for high energy density supercapacitor devices

Activated carbon with porous structures attracted much attention for supercapacitor applications due to their viability, sustainability, and eco-friendliness. In particular, decentralized and sustainable production of materials related to energy technologies would be enabled through bio-source derived materials. This is the first report on Momordica Charantia as a bio precursor for making electrode material. Herein, KOH-treated porous activated carbon was prepared under different activation temperatures using the pericarp of Momordica Charantia. The activated carbon synthesized at an activation temperature of 900 celcius showed a high specific surface area of 1126 m(2) g(-1). It exhibited a specific capacitance of 186 F g(-1) at 1 A g(-1). Symmetric supercapacitor device fabricated delivered an energy density of 8 Wh kg(-1) at a power density of 750 W kg(-1) with 98% capacitance retention after 5000 cycles in 1 M H2SO4. A further improvement of energy density to a maximum of 23 Wh kg(-1) and a maximum power density of 6000 W kg(-1) was achieved using dual redox mediators (KI + HQ) in H(2)SO(4)due to the redox activity of the I-2/I- and Q/HQ redox species at the positive electrode.