Preparation of finely dispersed nanographite

We have developed a convenient single-step method for producing stable nanographite dispersions from natural graphite in various solvents using high-power sonication. Nanographite dispersions in water are shown to be stable for several weeks, and aqueous nanographite dispersions containing a surfactant are stable for several months. Nanographite samples prepared from aqueous nanographite dispersions have been characterized by various physicochemical techniques (including X-ray diffraction and Raman spectroscopy). Interference microscopy, transmission and scanning electron microscopy, and atomic force microscopy have been used to examine the morphology and determine the size of nanographite particles. The nanographite platelets are 300–500 nm in lateral size and 20–40 nm in thickness, which corresponds to 30–50 graphene layers.