Coprinus Comatus-Based Nitrogen-Doped Active Carbon for High Performance Supercapacitor

Abstract

Coprinus comatus-based nitrogen-doped activated carbon (N-ACC) is prepared by chemical activation and nitrogen-doped methods. The N-ACC possesses large specific surface areas (976.96[Formula: see text]m2[Formula: see text]g[Formula: see text]), high nitrogen contents (11.53[Formula: see text]wt.%), and super hydrophilicity. As electrode material for supercapacitors, the N-ACC shows remarkable electrochemical performance, such as 346[Formula: see text]F[Formula: see text]g[Formula: see text] maximum specific capacitance at a current density of 1[Formula: see text]A[Formula: see text]g[Formula: see text], which retains 260[Formula: see text]F[Formula: see text]g[Formula: see text] even at a high current density of 10[Formula: see text]A[Formula: see text]g[Formula: see text] (about 75% capacitance retention) in 2[Formula: see text]M KOH aqueous electrolyte. The assembled N-ACC//N-ACC symmetric supercapacitor exhibits energy density of 14.63[Formula: see text]Wh[Formula: see text]kg[Formula: see text] at power density of 810[Formula: see text]W kg[Formula: see text], and excellent cycling stability with 92% specific capacitance retention after 10000 cycles in the voltage range 0–1.8[Formula: see text]V in 0.5[Formula: see text]M Na2SO4 aqueous solution. These results indicate that the N-ACC as electrode materials can be used for high performance supercapacitors.