Topological changes of vapor grown carbon fibers during heat treatment Original Research Article

The topological change of the surface of vapor-grown carbon fibers (VGCFs) as a function of heat treatment temperature was observed using FE-SEM, STM and AFM. The morphological change at the micrometre scale from a smooth surface, to a rope-like structure, and to a grain-like structure was closely related with the volume change, especially due to the annular fiber form. The extent to which the micro-domain grows by heat treatment is limited by the diameter of the fiber. The appearance of a Moiré pattern provided evidence for the graphitization process from turbostratic to three-dimensional graphite.