▎ 摘　　要

Graphene has lots of attractive properties. However, most of its optimal properties are only associated with individual sheets. Producing a colloidal form of graphene can effectively avoid graphene aggregation and thus maintain its original performance. In this paper, an electrolytic method was utilized to prepare graphene colloids. Initially, graphene oxide ( GO) was produced from graphite by a pressurized oxidation method. The high concentration of H+ or OH- was found to facilitate the aggregation of GO. Then, GO was reduced by nascent hydrogen, which was generated by reducing hydrogen ions on an iron cathode in the electrolytic method. X-ray diffraction, Raman spectrum, thermogravimetric analysis and x-ray photoelectron spectroscopy analyses indicated that the nascent hydrogen can effectively reduce GO to graphene. Atomic force microscopy analysis and dispersibility evaluation of graphene colloids proved that the novel electrolytic method can prepare well-dispersed single-layer graphene colloids.