▎ 摘　　要

A new method for preparing graphene colloidal suspension is studied by thermal reducing graphene oxide in N-methylpyrrolidone (NMP) and -Butyrolactone (GBL) at 200 degrees. Without assistance of polymeric or surfactant stabilizers, thermal reduction and dispersion of reduced graphene sheets are performed in one pot, and stable suspensions are confirmed by transmission electron microscope (TEM) and atomic force microscope (AFM) technic. Experimental results such as thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS) and Raman indicate bulk cleavage of oxygen-containing functional groups and restoration of graphite structure on reduced graphene oxide sheets. The study contributes to the preparation of graphene-based nanocomposites using this quick and low-cost processing technique.