Synthesis of columnar carbon nanoscrolls by vibratory milling of expanded graphite

Columnar carbon nanoscrolls are synthesized by vibratory milling of expanded graphite under ambient atmosphere. Different from tubular carbon nanoscrolls, these nanoscrolls are solid and their compactly stacked layers are parallel to one another, with an interlayer spacing of 0.34 nm. The columnar structure of the carbon nanoscrolls is independent of their diameters. The formation of this columnar structure can be attributed to the thinness of graphene nanosheets, the elevated temperature, and the vacancies of graphene nanosheets produced by prolonged ball milling.