Synthesis of graphene oxide nanosheets by electrochemical exfoliation of graphite in cetyltrimethylammonium bromide and its application for oxygen reduction

Abstract

An electrochemical method is reported for the production of graphene oxide (GO) and graphene nanosheets using the following steps: electrochemical intercalation of cetyltrimethylammonium bromide (CTAB) into graphite followed by the electrochemical exfoliation of a CTAB-intercalated graphite electrode. These electrochemical processes yield a stable colloidal GO/CTAB suspension. Then, exfoliated GO was used as a precursor at cathodic potentials (completely reduced potential: −1.5 V) by cyclic voltammetry or cronoamperometry. The colloidal GO/CTAB suspension and electrochemically reduced graphene oxide (RGO) nanosheets have been carefully characterized by spectroscopic and electrochemical techniques in comparison to the stable colloidal graphene/sodium dodecyl sulfate suspension. Particularly, FTIR spectra indicate that a variety of the oxygen-containing functional groups have been produced from the graphite plane by electrochemical oxidation. UV-vis spectra of GO/CTAB suspensions show that a large amount of GO is obtained after successive electrochemical intercalation and exfoliation processes. Finally, the straightforward synthesis of RGO/CTAB composites provide a low-cost and high performance for oxygen reduction reaction (ORR), which is also a promising strategy for the synthesis of various GO/cationic surfactants composites.