A facile route for nitrogen-doped hollow graphitic carbon spheres with superior performance in supercapacitors

A novel template-free approach to prepare nitrogen-doped hollow carbon microspheres with graphitic carbon shells (NHGCSs) was reported. The obtained NHGCSs by the direct pyrolysis of solid melamine-formaldehyde (MF) resin spheres exhibit excellent capacitance performance. The specific capacitance reaches 306 F g(-1) at a current density of 0.1 A g(-1) (in 2 MH2SO4), and remains as high as 230 F g(-1) even at a high current density of 3 A g(-1), which indicates the optimistic prospects for using NHGCSs as super-capacitor electrode materials.