Structural transformation and field emission enhancement of carbon nanofibers by energetic argon plasma post-treatment

摘要

Vertically aligned carbon nanofibers (CNFs) grown by plasma enhanced chemical vapor deposition (PECVD) were transformed into cone-shaped nanostructures after treatment by argon (Ar) plasma. Significant enhancement of field emission characteristics of the post-treated CNFs has been achieved. Analysis by electron microscopy and energy dispersive spectroscopy (EDS) suggests that the structural transformation is a result of a cosputtering/deposition process by energetic plasma ions. The enhancements can be attributed to the combining effects of an additional Si/C layer coverage, catalytic nanoparticles removal and the sharpening of CNFs tips. The argon plasma post-treatment processes developed here can be easily extended to in situ PECVD processes for fabricating CNFs based emitters.