Novel laurel aromatic evergreen biomass derived hierarchical porous carbon nanosheet as sustainable electrode for high performance symmetric supercapacitor

Abstract

Biomass-based activated carbon with features combinations of 2D nano-structure, 3D hierarchical porous, and self−/co-doping active heteroatoms have proven excellent performance as sustainable electrodes for high-energy supercapacitors. Therefore, this study aims to obtain activated carbon with 2D nanosheet, 3D hierarchical pores, and self‑oxygen doped from the typical aromatic biomass of Indonesian laurel aromatic evergreen (ILAE), Laurus nobilis. It was carried out using a fast and toxic residue-free strategy as an active material for symmetrical supercapacitors. The optimization of the activated carbon structure was controlled through the activating agent ratio in high-temperature pyrolysis. It was discovered that the prepared ILAE carbon material has a 2D gauze-like nanosheet structure with a hierarchical pore network that enables fast and efficient accessibility. Furthermore, the porosity of the optimal ILAE-activated carbon possessed enriched micropores of 88 % and confirmed mesopores of 12 % with a high carbon content of 95.07 % and 4.49 % functional oxygen as self-doping heteroatom. In two-electrode configuration systems, the ILAE nanosheet-activated carbon-based supercapacitor exhibits excellent electrochemical performance with a high specific capacitance of 205 F g−1 at 1 A g−1 in a 1 M H2SO4 electrolyte. Furthermore, their capability rate was maintained at 81.16 % in 10 A g−1 with an optimum coulombic efficiency of 81.66 %. Moreover, the symmetrical supercapacitor device in aqueous electrolyte performed excellent energy output behaviors as high as 21.56 Wh kg−1 with maximum power output of 1.101 kW kg−1, respectively. This indicated that the novel ILAE biomass proves high potential as a source of activated carbon enrich-nanosheet with 3D hierarchical pores prepared with the up-to-date approach to enhance the performance of electrochemical energy storage devices.