Electrochemical synthesis of few layer graphene in subcritical electrolyte

A novel top-down approach to the graphene synthesis combining electrochemical ion intercalation and supercritical fluid intercalation is proposed. Potentiostatic intercalation of BF4- anion into highly-oriented pyrolytic graphite in a subcritical electrolyte based on a CO2/acetonitrile mixture in a specially designed 3-electrode highpressure electrochemical cell has been performed. The intercalation stage of the anion inside working electrode made of highly-oriented pyrolytic graphite is studied by means of Raman spectroscopy. The dispersed solid particles contained in the electrolyte have been analyzed after the intercalation and high-pressure cell decompression by means of atomic force and transmission electron microscopies. As a result, few (2-4) layers graphene flakes with partial crystallinity have been detected in the electrolyte. Additionally, the intercalated graphite electrode has been ultrasonicated, which also resulted in the formation of few layer graphene stacks with lower lateral dimensions and higher thickness.

Automated summary

A novel top-down approach to graphene synthesis combining electrochemical ion intercalation and supercritical fluid intercalation has been proposed. The intercalation of BF4- anion into highly-oriented pyrolytic graphite using a subcritical electrolyte based on a CO2/acetonitrile mixture in a specially designed high-pressure electrochemical cell has been studied. Few-layer graphene flakes and stacks have been obtained through this method.