Electrochemical Exfoliation of Graphite into Nitrogen-doped Graphene in Glycine Solution and its Energy Storage Properties

Electrochemically anodic exfoliation of graphite has been developed for nitrogen-doped few -layer graphene sheets (N-FLGS), demonstrating high N-doping levels of 6.05 atom%. The process for the preparation of N-FLGS is involved with the intercalation of glycine anions H2NCH2COO into the graphite layers, electro-polymerization of large electro-oxidation products H2NCH2CONHCH2, and in situ N -doping in the graphite layer. Transmission electron microscopy, X-ray photoelectron spectroscopy, Xray diffraction, and Raman spectroscopy were employed to characterize the structure and properties of the N-FLGS. The as -fabricated N-FLGS utilized as electrode materials for supercapacitor exhibit enhanced electrochemical performance, including excellent cycling stability (the capacitance ratios after 10 000 cycles is 96.1%) and a remarkable rate capability (184.5 Fg (1) at 1 A g (1), 132.7 Fg (1) at 50 A g (1)). (C) 2016 Elsevier Ltd. All rights reserved.