Functionalization of Multiwalled Carbon Nanotubes using Cold Plasma Treatment and their Electrochemical Performances

Functionalization of multiwalled carbon nanotubes (MWNTs) are proceeded with cold plasma generated in N-2 and air atmosphere. X-ray photoelectron spectroscope (XPS) shows that the nitrogen and/or oxygen elements are incorporated into MWNTs. The total nitrogen contents are approximately equal in N-2 and air atmospheres, while oxygen content is increased significantly in air atmosphere, the species and content of the functional groups depend on the applied gases. Transmission electron microscope (TEM) shows that the morphology of functionalized MWNTs is almost the same to pristine MWNTs, although functional groups and defects increase. The electrochemical experiments results demonstrate that introduction of functional groups enhance the pseudocapacitance, while the cyclic stability of the functionalized MWNTs is as well as the pristine MWNTs.