Key Words:CAPACITY BATTERY ANODES; ACTIVATED CARBON; ULTRAHIGH CAPACITANCE; GREEN SYNTHESIS; SURFACE-AREA; NITROGEN; NANOSHEETS; OXYGEN; TEMPLATE

Abstract:Plant ash and eggshells are explored to serve as natural activation agent and template to prepare N, O, and S codoped carbon (KDPC) with porous structure from biomass - Descurainia sophia seeds. The obtained KDPC-20-600 shows a high yield of 75 % and a relatively high specific capacitance of 250.5 F g-1 at 0.5 A g-1 in 2 M KOH, which maintains 232.8 F g-1 at 1.0 A g-1, superior or comparable with commercial active carbon. Also, the KDPC-20-600 demonstrates a long-term cycling life with a capacitance retention of 99.0 % after 10,000 cycles. Furthermore, the KDPC-20-600-based symmetric supercapacitor displays a high energy density of 24.8 Wh kg-1 at 1050 W kg-1 in 1 M Na2SO4. The findings indicate that environmentally friendly agents (e.g., plant ash, eggshells) can substitute harsh chemicals (e.g., KOH, H3PO4) to synthesize porous carbon from biomass materials in-situ doped with heteroatoms. Therefore, this cost-effective, environmentally friendly and sustainable process to obtain porous carbon will shed light on the development of electroactive materials for energy storage and conversion devices.

Volume:134

Issue:wu

Translation or Not:no