Nitrogen-doped mesoporous reduced graphene oxide for high-performance supercapacitors

Abstract

We report a simple method to prepare N-doped mesoporous reduced graphene oxide (RGO) via the pyrolysis of poly (methyl methacrylate)–graphene oxide (PMMA–GO) and PMMA–RGO composites in a mixed nitrogen and ammoniac atmosphere. The pyrolysis of the PMMA–GO resulted in a heavily nitrogen-doped RGO aerogel with a nitrogen content of more than 5.0 at%, whereas crumpled RGO with a surface area of up to 766 m² g⁻¹ was obtained by the pyrolysis of PMMA–RGO. A supercapacitor based on the N-doped mesoporous RGOs exhibited an excellent specific capacitance of up to 290 F g⁻¹ at a current density of 1 A g⁻¹ and good electrochemical stability with a capacitance retention of about 85% after 1000 cycles. Moreover, by using an ionic liquid as an electrolyte within a potential range of 0–4 V, a remarkable energy density of up to 149 W h kg⁻¹ was achieved.