Electrospun Carbon Nanofibers; structural and electrical properties

CNF were prepared by electrospinning polyacrylonitrile nanofibers followed by stabilization and carbonization.Electrical transport and Hall Effect on carbon nanofibers annealed at 700 °C–1400 °C was studied. It has been observed that the ratio of the D to G peaks in Raman spectroscopy and the FWHM of 100% peak (26 °) in the XRD spectra decreases as the annealing temperature increases, hence the crystallinity of CNF increases as the temperature increases. Also, the diameter of the carbon nanofibers decreases from 51.17 nm to 15.89 nm as the annealing temperature increases. CNF have been found to exhibit a semiconducting behavior in the temperature range of 350-10 K with their room temperature resistivity’s varying from 10 to 50 mOhm.cm. The Hall Effect show that Hall coefficient value was -5.6x10^-10 cm³/C at 300 K for the CNF that were annealed at 1200 °C.The electron carrier concentration and their mobility were calculated to be 1.1x10²⁰/cm³ and 25.8 cm²/Vs.The electronic charge carrier concentration is almost an order of magnitude higher than the values reported for CNF synthesized under similar conditions. Due to semiconducting nature of CNF, superior carrier concentration, and carrier mobility CNF have the potential to be used in non-silicon based integrated circuits.