Preparation of nitrogen-doped graphene and its supercapacitive Properties

Abstract

Nitrogen-doped graphene was synthesized by the hydrothermal method with graphene oxide (GO) as the raw material and urea as the reducing-doping agent. The morphology, structure, and components of the as-produced graphene were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption-desorption analysis, and electrical conductivity measurements. The results showed that nitrogen was doped into the graphene plane at the same time as the GO sheets were reduced, and the nitrogen content was between 5.47%- 7.56% (atomic fraction). In addition, the electrochemical performance of the graphene was tested. Nitrogen-doped graphene with a nitrogen content of 7.50% showed excellent capacitive behavior and long cycle life. The first cycle specific discharge capacitance for the material was 184.5 F· g -1 when cycled at 3 A· g -1, and 12.4% losses were found after 1200 cycles in an aqueous electrolyte of 6 mo· L -1 KOH. © Editorial office of Acta Physico-Chimica Sinica.