Preparation of biomass-derived activated carbon from golden needle mushroom roots for supercapacitor electrodes

Herein, an original activated carbon (AC) is prepared using golden needle mushroom roots and potassium hydroxide. After carbonization under 500 °C, AC-5 exhibits good graphitization degree, appropriate nitrogen and oxygen elements, large specific surface area, and micro-meso porous structures. Notably, AC-5 as electrodes in supercapacitors has excellent electrochemical performances, e. g. high specific capacitance (360.4 F/g), impressive rate capability (77 %, from 10 mV/s to 200 mV/s), and outstanding cycling durability (99.56 %, after 10,000 cycles).