Fabrication of Graphene by Electrochemical Exfoliation in Alkaline Electrolytes

Abstract

Fabrication of graphene was demonstrated by electrochemical exfoliation of graphite in an ammonium hydroxide solution. The processing parameter of applied voltage was optimized to accomplish graphene productivity and desired chemical composition. Images from the atomic force microscopy showed graphene sheets with lateral sizes of several hundred nanometers. Images from the transmission electron microscopy indicated the existence of stacked graphene sheets with thickness of a few graphene layers. Raman spectroscopy confirmed variation of as-synthesized graphene and bulk graphite. X-ray photoemission spectroscopy suggested the formation of graphene oxide at large voltage.