Deposition of Au colloids on plasmachemically modified carbon nanofibers

• Published in: Carbon (New York) Vol. 46; no. 5; pp. 759 - 765
• Main Authors: Kvande, Ingvar, Øye, Gisle, Hammer, Nina, Rønning, Magnus, Raaen, Steinar, Holmen, Anders, Sjöblom, Johan, Chen, De
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.04.2008; Elsevier Science
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Materials science; Physics; Specific materials; Nanofiber; Carbon; Colloids; Deposition
• ISSN: 0008-6223; 1873-3891
• DOI: 10.1016/j.carbon.2008.01.033

The surface properties of fishbone (FB) carbon nanofibers (CNFs) were altered. This was achieved by H 2O-plasma treatment (FB-plasma) and oxidation in HNO 3 (FB-HNO 3). By zeta-potential measurements, the surfaces of as-grown and acid treated CNFs were found to be negatively charged at all pHs. Meanwhile, basic entities were introduced by H 2O-plasma treatment, indicated by an isoelectric point of pH 4.6. Ultraviolet–visible measurements indicated the successful deposition of negatively charged Au colloids on FB-plasma, and incomplete deposition on FB-HNO 3. The nature of the basic sites accommodating colloid deposition is discussed based on X-ray photoelectron spectroscopy (XPS) results. The XPS study indicated significant differences in the type and amount of surface groups. Also, a variation in the fraction of defect and/or edge sites was found. The possible sites responsible for colloid immobilization are discussed based on the XPS results. Plasma treatment is demonstrated as a simple and effective procedure for altering the surface characteristics of CNFs.