Fe-CATALYZED IN SITU GROWTH OF CARBON NANOFIBERS ON PAN CARBON FIBERS

In order to investigate the application of vapor grown carbon nanofibers in C/C composites, the isothermal chemical vapor deposition method was used with PAN carbon fibers as substrates, ferrocene as catalyst precursor, propylene as carbon source and nitrogen as carrier gas. The deposition reaction was carried out at 880?℃ and 920?℃ under pressures between 1.0 and 1.3?kPa. The surface structure of PAN carbon fibers was studied by scanning electron at different deposition times. It was found that there were many vapor grown carbon nanofibers around the PAN carbon fibers at 880?℃ after 4?h deposition. At 920?℃, however, pyrolytic carbon particles were dominant with only a small quantity of vapor grown carbon fibers. The reason for this is that the Fe catalyst particles were covered by pyrolytic carbon. The mechanism of Fe catalyzed in situ deposition of carbon nanofibers is discussed.