Gas-phase surface functionalization of multi-walled carbon nanotubes with vacuum UV photo-oxidation

摘要

For bulk processing of carbon nanotubes,an important first step in adhesion to the nanotubes is often liquid-phase functionalization through chemical oxidation with acids (e.g.,nitric and sulfuric),peroxides and/or potassium permanganate.In comparison,gas-phase photo-oxidation can be an alternative to introduce oxygenated functional groups on the surfaces of carbon nanotubes without the generation of liquid waste.In the present study,vacuum UV photo-oxidation of multi-walled carbon nanotube (MWNT) paper was investigated downstream from an Ar microwave plasma.X-ray Photoelectron Spectroscopy (XPS) was used to detect the carbon- and oxygen-containing functional groups in the top 2-5 nm of the sample's surface.The current results are compared to previous investigations using MWNT powder and single-walled carbon nanotube (SWNT) paper showing decreased levels of oxidation in MWNT samples.