FLUORINE-INTERCALATED CARBON-FIBERS .3. A TRANSMISSION ELECTRON-MICROSCOPY STUDY

A high resolution transmission electron microscopy study of fluorine-i ntercalated carbon fibers has been carried out on two types of host ma terials: high-temperature treated pitch-based and PAN-based fibers. TE M images and corresponding Fourier transforms have shown that only sta ge-1 compounds and graphitic-type domains are detected in the experime nt conditions. In particular, no interlayer spacing corresponding to h igher staged materials have been noticed. The observed results can be correlated to the ratio of semi-ionic to covalent F-C bonding previous ly determined by XPS. The disorder mostly depends on the nature of the host fiber and on the amount of mobile species that may react with th e graphene layers during the deintercalation process, which is favored by the high-vacuum conditions.