Acetone dissolution to prepare N-doped hierarchical porous carbon for supercapacitor

Abstract

The hierarchical porous carbon (HPC) materials have rich porous structure, high specific surface area and reasonable porosity for a wide range of applications in many fields, such as catalysis, adsorption, and energy storage, etc. Although some synthetic strategies have been developed, efficient preparing HPC materials remains challenging. In this work, we propose a method to prepare N-doped hierarchical porous carbon (NHPC) by acetone dissolution following co-assembly process. 1-Alkyl-3-methyl imidazole bromide ([C18Mim]Br), tetraethyl orthosilicate (TEOS) and resorcinol-formaldehyde were co-assembled to form a pleated sheet composite material, where [C18Mim]Br induced formation of the sheet structure and also led to nitrogen doping in the carbon skeleton. TEOS created a mesoporous structure and increased specific surface area, while acetone dissolved the oligomer of the resin, creating a macroporous structure, but destroying the morphology of the sheet. At an appropriate amount of acetone, the resulting NHPC exhibits the hierarchical porous structure, high specific surface area and N-doping characteristics. When used as a supercapacitor material, NHPC exhibits the specific capacitance is as high as 241 F g−1 at 1 A g−1. Furthermore, the symmetric supercapacitor manufactured with NHPC has a power density of 4.1 kW kg−1, an energy density of 2.56 Wh kg−1, and demonstrates excellent cycle stability of up to 92.82%, exhibiting the potential as good supercapacitor materials.