Mangosteen peel waste derived Sulfur-Oxygen self-dual-doped hierarchical porous carbon nanofiber for ultrahigh energy of solid-state supercapacitor

Herein, an innovative integrated employed dual-gas pyrolysis approach to produce synergistically enriched S and O self-dual-doped carbon nanofibers (SOCAF) for supercapacitor applications. The precursors were sourced mangosteen peel were prepared via N₂/CO₂-gas integrated pyrolysis. The SOCAF exhibited a wormhole-like nanofibers, high porosity (962.415m²/g), micropore to mesopore ratio of 1:1, and robust S(7.25 %) and O(20.53 %) self-dopants. Subsequently, the optimal electrode, operated within a dual-cylinder system, demonstrated excellent electrochemical performance, achieving a capacitance of 231F/g at 1 A/g, 87 % rate capability, high coulombic efficiency of 98 %, and low resistance of 0.12 Ω. Moreover, the enhanced faradaic effect, with 16 % pseudocapacitance observed at optimized active cell, resulted in a 13.3 Wh/kg energy output at 393 W/kg in the symmetric supercapacitor system. This study underscores a rational approach to explore the promising potential of mangosteen peel as a carbon source for the synthesis of S and O-rich self-doping nanofiber architectures, aiming to optimize advanced energy storage devices.