Multi walled carbon nanotubes deposited on metal substrate using EPD technique. A spectroscopic study

The work reports the results of manufacture of carbon coatings on the surface of stainless steel. Multi walled carbon nanotubes (MWCNTs) were used to obtain carbon coatings by electrophoretic deposition technique (EPD). Before deposition MWCNTs were purified and surface functionalised. After purification and functionalization CNTs contained oxygen functional groups on its surface. The experiments were made in two model systems, differing in the type of suspensions of carbon nanotubes used in the electrophoretic deposition process. For the preparation of the suspensions, water and isopropanol were used without any additional components. Both experiments involved the application of the same type of nanotubes, as well as identical processing parameters of EPD. The structural analysis of both types of coatings was performed using Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). It was pointed out that the structures of the coatings are different, depending on the type of the applied suspension. The degree of the structure’s arrangement in both analysed layers is different; also the types of oxygen–carbon combinations in both coatings are essentially dissimilar.