Interconnected activated carbon nanofiber derived from mission grass for electrode materials of supercapacitor

Abstract

The porous carbon electrode materials for supercapacitors derived from biomass waste attract lots of attention due to their natural abundance and low cost. This study therefore aims at developing a cost-effective and sustainable method for synthesising porous activated carbon derived from mission grass biomass waste (MG). The one-stage integrated pyrolysis for carbonisation, physical activation, and KOH activation was used to obtain porous activated carbon monolith. The surface morphology and pore structures consist of interconnected activated carbon nanofiber with high carbon content of 90.45%. The KOH impregnation successfully changed the morphology from the rod-like shape into a nanofiber structure. Due to their synergistic effect, the specific capacitance enhanced from 115 to 171 F g−1 in 1 M H2SO4 aqueous electrolyte with an egg duck shell membrane as a separator. The result showed that the maximum energy and power densities were 23.75 Wh kg−1 and 96.94 W kg−1, respectively. Therefore, these unique properties enable the mission grass to become a high potential for porous carbon electrode materials as supercapacitor energy storage.