Dielectric barrier discharge plasma functionalization of carbon nanotubes surface CO2 and N2 treatments

Multi walled carbon nanotubes (MWCNTs) were modified by CO
₂
/N
₂
plasma produced by dielectric barrier discharge (DBD). The effects of gas and modification time on the surface functional groups of MWCNTs were studied by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Raman spectroscopy was used to study the effect of plasma treatment on the surface structure and defect level of MWNTs. Results the oxygen-containing groups of MWNTs were increased after plasma treatment. CO
₂
plasma could promote the formation of carboxyl groups on the surface of MWNTs. With the increase of modification time, the contact angle of water in the modified MWNTs decreases, and the decrease rate is the fastest in the first 120 seconds, and the treatment effect is more obvious when using N
₂
/CO
₂
mixture. After plasma treatment, the surface morphology of MCNTs becomes rough, but the structure of MWCNTs is not destroyed.