N, S Co-doped mesoporous carbon derived from kitchen waste for high-performance supercapacitor applications

Biomass is an easily available and environmentally benign carbon sources for energy storage applications. In this work, the kitchen waste was converted into valuable mesoporous carbon for energy storage applications to support Sustainable Development Goal (SDG). The biomass was pre-activated and carbonized with N and S co-doped through a high temperature process. The activated carbon (AC) and nitrogen and sulfur dual heteroatom doped AC (N-S-AC) samples were utilized for the electrochemical performance. Moreover, the capacitance (C p ) value is 488 F g -1 for N-S-AC and 293 F g -1 for AC under three-electrode characteristic. In addition, the capacitance retention (CR) percentage of the N-S-AC shows 93.91% which is larger than AC material (60.69%) and the coulombic efficiency (CE) of the N-S-AC and AC electrodes are 100.89% and 99.70% over 2000 cycles. Moreover, the symmetric supercapacitor device was constructed using the N-S-AC under 6 M KOH electrolyte. The N-S-AC//N-S-AC shows a higher C p of 118 F g -1 , and the E is 23.66 Wh kg -1 at 600 W kg -1 . Moreover, the device exhibts the excellent cyclic stability of 94.14% over 8000 cycles. The excellent activity of the N-S-AC electrode is due to the addition of N and S co-doping was improving the wettability and ionic conductivity to the activated carbon which leads enhanced overall electrochemical performance of the N-S-AC electrode.