Electrochemical preparation of free-standing few-layer graphene through oxidation-reduction cycling

Free-standing few-layer graphene (FFG) were electrochemical-exfoliated from a graphite column via oxidation-reduction cycling (ORC). FFG with the width up to 500nm, and length up to 800 nm were successfully obtained. The atom layers, crumpled morphology and scroll that concerned with structure defect of FFG were found through transmission electron microscope (TEM). The presence of defects on FFG was proved by Raman spectroscopy, and the surface chemistry informations about oxygen-containing groups were collected from XPS and FTIR data. For the potential applications of this FFG, the capability of electron transfer was studied by AC impedance and the electro-catalytic oxidation of nicotinamide adenine dinucleotide (NADH) was investigated. The results showed that this method can provide valuable protocol for preparation free-standing few-layer graphene, which may facilitate both its synthesis and applications. (C) 2011 Elsevier B.V. All rights reserved.