Surface and electrochemical characterisation of CVD grown graphene sheets

Abstract

Morphological and electrochemical properties of graphene sheets grown by chemical vapour deposition (CVD) onto Ni foil were investigated. Glassy carbon (GC) and highly oriented pyrolytic graphite (HOPG) electrodes were used for comparison. Raman spectroscopy, high-resolution scanning electron microscopy and atomic force microscopy confirmed that multilayer graphene was formed on the Ni substrate by the CVD method. Raman spectra of HOPG and CVD graphene revealed that these materials were almost defect-free. In contrast to bare GC, the electron transfer kinetics towards the Fe(CN)63−/4− redox couple was significantly slower on HOPG and CVD graphene surfaces. In addition, HOPG and CVD-grown graphene electrodes were rather inactive for oxygen reduction in alkaline medium compared with bare GC. Similar electrochemical behaviour of HOPG and CVD graphene surfaces was in evidence.