A highly efficient gas-phase route for the oxygen functionalization of carbon nanotubes based on nitric acid vapor

A simple, highly effective method for the functionalization of CNTs with HNO3 vapor is developed, thus eliminating separation by filtration. A significantly higher amount of oxygen species compared to conventional wet HNO3 treatment was detected by X-ray photoelectron spectroscopy, and the morphology and the degree of agglomeration did not deteriorate because of the treatment.