Oxidation behavior of multiwall carbon nanotubes with different diameters and morphology

► We study oxidation of MWNT with different diameters and morphology. ► Oxidation induces defects and formation of oxygen-containing surface groups. ► Amount of surface functions depends of MWNT's and oxidizer's nature. ► Oxidation decreases conductivity of MWNT and changes its type. ► Commonly used oxidation step of MWNT must be used with caution.