Areca nut–derived porous carbons for supercapacitor and CO2 capture applications

The preparation and application of biomass-derived carbons in supercapacitor and CO2 absorption have inspired increasing attention due to the ease of fabrication, cost-effectiveness, and sustainability of the meso-/microporous carbon produced from various biological precursors. With this respect, areca nut (AN) was used to derive porous carbons, through carbonization and KOH activation, at various temperatures without or in the presence of N-doping agent of adenine. KOH-activation temperature and the N-doping agent are parameters influencing the surface area, porosity, and the micro-/mesoporous structure of the porous carbons. Appropriate adjustment of the preparation parameters resulted in porous carbons with extremely high Brunauer–Emmett–Teller surface area (SBET, up to 3723 m2/g), excellent CO2 absorption capacity (up to 4.8 mmol/g) at 25 °C, and outstanding capacitive performance with high specific capacitance (up to 419 F/g) and retention (> 91%) over 1000 cycles. Effect of preparation parameters on the micro-/mesoporous structures and the resolved SBET values, CO2 absorption capacity, and the capacitive performances of the porous carbons are the main focuses of this research.