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

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 mes-opores 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 per-formed 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.

Automated summary

Biomass-based activated carbon with 2D nano-structure, 3D hierarchical porous, and self-/co-doping active heteroatoms has been proven to be an excellent sustainable electrode material for high-energy supercapacitors. This study aimed to obtain activated carbon with these features from Indonesian laurel aromatic evergreen biomass and optimize its structure through high-temperature pyrolysis. The prepared ILAE carbon material exhibited a 2D gauze-like nanosheet structure and a hierarchical pore network, leading to excellent electrochemical performance in symmetrical supercapacitors.