Porous carbon materials derived from areca palm leaves for high performance symmetrical solid-state supercapacitors

Areca palm leaves derived porous carbon material as the electrode for symmetrical solid-state supercapacitors (SSCs). The areca palm leaves biomass was processed using a fast carbonization method followed by in situ chemical activation. The structures and compositions of these biomass-derived carbon materials were characterized using X-ray diffraction, Raman spectroscopy, and X-ray photoelectron spectroscopy, respectively. One of the biomass-derived porous carbon materials, AR2, was a lightweight carbon material that possessed a large surface area of 876 m2 g–1. Electrochemical studies revealed that AR2 possessed a high specific capacitance of 262 F g–1 at a scan rate of 5 mV s–1. We fabricated symmetrical SSCs featuring these carbon material as major (80 wt%) components of the electrodes and poly(vinyl alcohol)–Li2SO4 as gel polymer electrolyte. The optimal supercapacitor (SAR2) involving AR2 exhibited a specific capacitance of 132 F g–1 at a current density of 0.5 A g–1 and an energy density of 10.3 W h kg–1 at a power density of 375 W kg–1, and durability of retaining 92% of its initial capacitance after 5000 cycles—performance that is the excellent values reported for devices featuring derived from biomass.