Nitrogen-doped mesoporous carbons originated from ionic liquids as electrode materials for supercapacitors

Abstract

Nitrogen-doped mesoporous carbon materials are prepared via carbonization of a room temperature ionic liquid, 1-butyl-3-methylimidazolium dicyanamide (BMIMdca), using a mesoporous silica template (SBA-15). The nitrogen content and nanostructure of the resultant carbon materials are highly dependent on the carbonization temperature. The produced porous carbon materials were further applied as the electrode materials for supercapacitors. The porous structure and nitrogen functionalities enable carbon materials with a specific capacitance of 210 F g⁻¹ at a current density of 1 A g⁻¹ in a 6 M KOH aqueous solution. Furthermore, the nitrogen-doped porous carbon materials maintain a high capacitance retention capability (95%) after 1000 cycles at a current density of 1 A g⁻¹, indicating that this kind of nitrogen-doped carbon material originated from room temperature ionic liquids is a promising electrode material for high-performance supercapacitors. These results may provide a facile synthesis of sulfur and nitrogen or multi-element doped porous carbon materials originated from ionic liquids for supercapacitors.