Chestnut-derived porous carbon with O and N co-doping as electrode for high-performance supercapacitor

The capacitive performance of carbon materials as supercapacitor electrode is synergistically influenced by the surface porous structure, graphitization structure, and surface atomic doping. However, simple realization of their synergistic regulation still faces significant challenges. Based on the biological porous structure, heteroatom-rich content and low cost of chestnut, this work adopt chestnut as precursor to prepare carbon electrode, of which the pores, graphitization, and surface atomic doping are synergistically regulated by simply changing the activation temperature. The optimized carbon electrode possesses a hierarchical porous structure with partial graphitization and O and N co-doping. Benefited from these merits, the chestnut-derived porous carbon as a supercapacitor electrode, can achieve a high specific capacitance of 328.6 F/g at 1 A/g, which still retains 80.8% when the current density enlarging to 20 A/g. By packaging the symmetric electric double-layer capacitor, the device exhibits a specific capacitance of 63.6 F/g at 1 A/g, delivering an energy density of 12.7 W center dot h/kg at a power density of 600 W/kg. The stability of the device is tested at a current density of 20 A/g, which shows a capacitance retention rate of up to 90% after 10000 charge-discharge cycles.