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

Abstract 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 H 2 NCH 2 COO − into the graphite layers, electro-polymerization of large electro-oxidation products H 2 NCH 2 CONHCH 2 − , and in situ N-doping in the graphite layer. Transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray 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 F g −1 at 1 A g −1 , 132.7 F g −1 at 50 A g −1 ).