Room-Temperature Growth and Applications of Carbon Nanofibers: A Review

Ar⁺ ion bombardment of carbon surfaces (both bulk carbon and carbon-coated substrates) induced the growth of conical protrusions, and either aligned or nonaligned carbon nanofibers (CNFs) grew on the tips without any catalyst even at room temperature. CNFs thus grown were 20 ~ 50 nm in diameter and 0.2~10 mum in length. Very interestingly, no CNF grew without cone bases, and more than one CNF never grew on the respective cone tips. The solely standing and densely distributed CNFs were successfully applied to CNF-based scanning probe microscope (SPM) tips and field electron emission (FEE) sources, respectively. Since the myriad applications are possible, sputter-induced CNFs are believed to be quite promising as one-dimensional nanomaterials