Nitrogen-doped porous carbon derived from ginkgo leaves with remarkable supercapacitance performance

Abstract

Porous carbon derived from waste biomass has attracted great interest for supercapacitors due to high surface area, superior electrical conductivity, and excellent electrochemical properties. Moreover, it is of essential importance to control the microstructure for directing its application. Herein, nitrogen-doped porous carbon materials were synthesized from dried ginkgo leaves through alkali activation and the subsequent heating treatment, during which ureophil with high nitrogen content was used as additional nitrogen source. Ureophil not only obviously increases the nitrogen content of the sample, but also remarkably promotes the development of porous structure. Arising from the large specific surface area of 2947 m2 g−1 and high nitrogen content of 3.31 wt%, the as-prepared nitrogen-doped carbon achieves high specific capacitance (323.2 F g−1 at 0.5 A g−1) and superior rate capability (244 F g−1 at 20 A g−1). It also shows an outstanding cycling stability (0.00061% of capacitance decay per cycle for 12,000 cycles). The results demonstrate that our nitrogen-doped carbon derived from ginkgo leaves could be a potential candidate of electrode materials for practical applications in the fields of supercapacitor and other electrochemical energy storage and conversion devices.