Кислотно-основне титрування модифікованих багатошарових вуглецевих нанотрубок

• Datum: 2012
• Hauptverfasser: Gunko, G. S., Koval's'ka, E. O., Bolbukh, Y. M., Skwarek, E., Skubiszewska-Zieba, J.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2012
• Online Zugang: https://surfacezbir.com.ua/index.php/surface/article/view/477
• Назва журналу: Surface

The change of surface charge density depending on the pH of multiwalled carbon nanotubes by acid-base titration were investigated, which is based on determining the point of zero charge or point of equivalence. It was shown that the surface charge density of decorated nanotubes by cerium compounds are depended on the structure and surface composition and on the concentration oxygen containing groups and conditions of recovery of cerium in the process of decorating the nanotubes. The surface charge density of samples of unmodified carbon nanotubes, in comparison with decorated nanotubes is much lower, indicating a decrease of defects and content of surface functional groups. The surface charge density is increased in case of nanotubes oxidation with hydrogen peroxide. Modification with 3-aminopropyltriethoxysilane provides similar adsorption characteristics of the boundary layers above and below the isoelectric point. Modification of the oxidized nanotubes with oligomers 2-hydroxyethylmethacrylate with the charge changes to positive contributes the greatly increased the surface charge density, which provides the stability of the carbon nanotubes dispersion and increase the surface adsorption activity.