Synthesis of highly self-dual-doped O, P carbon nanosheets derived from banana stem fiber for high-performance supercapacitor electrode

Abstract

ABSTRACT In the present study, the development of a supercapacitor electrode using activated carbon (AC) derived from natural banana stem fiber (BSF) was presented. To enhance AC-BSF performance, nanosheets with favorable pore structures were incorporated, enriched with O and P doping. The production process involved crushing and heating BSF particles at high temperatures, with the addition of 0.5 M KOH as a reaction agent and developer of porous carbon structures with high density. The physical properties of AC-BSF were determined through density calculations, which revealed a shrinkage up to 34%. The material exhibited amorphous properties characterized by gentle peaks at diffraction angles (2θ) of 23.06–25.01° and 44.63–46.07°. The wettability of AC-BSF was attributed to the presence of O-H functional groups, micro-mesopores structure was confirmed by the type IV isotherm curve. AC-BSF-H2SO4 showed the highest specific capacitance value of 206.76 F/g. The increase in the performance of the AC-BSF electrode could primarily be attributed to its dual doping with O (24.15%) and P (4.37%) as well as the contribution of pseudocapacitance. These findings show the significant potential of O and P-doped multi-heteroatom carbon nanosheets derived from banana stem fibers in advancing new strategies for the development of high-energy-density and high-power supercapacitor materials.