The effect of the carbon nanotubes surface oxidation on the morphology and properties of poly(N-vinylcarbazole) coated multi-walled carbon nanotube nanocables

This article describes the effect of carbon nanotubes (CNTs) outer surface oxidation on the morphology and properties of poly(N-vinylcarbazole) (PNVC)-coated individual multi-walled CNT (MWCNT) nanocables. Surface oxidation of MWCNTs has been carried out by refluxing MWCNTs with 5 M nitric acid (HNO3) at 80 °C for 1 h. The PNVC-coated MWCNT nanocables are synthesized by in situ solid-state polymerization of N-vinylcarbazole monomers in the presence of oxidised MWCNTs (o-MWCNTs) at an elevated temperature. The PNVC-coated MWCNT nanocables are characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, field-emission scanning and transmission electron microscopes, photo-luminescence spectroscopy, and direct-current conductivity measurements. Results show that the uniform nanolayer coating of PNVC decreases the inherent bulk conductivity of MWCNTs, but significantly increases the optical properties of MWCNTs.