TY - JOUR A1 - Girard-Lauriault, Pierre-Luc A1 - Illgen, René A1 - Ruiz, J.-C. A1 - Wertheimer, M. R. A1 - Unger, Wolfgang T1 - Surface functionalization of graphite and carbon nanotubes by vacuum-ultraviolet photochemical reactions N2 - Graphite and multiwall carbon nanotube surfaces were functionalized by vacuum-ultraviolet induced photochemistry in NH3 or O2, in order to introduce amino- (NH2) or hydroxyl (OH) functionalities, respectively. Modified surfaces were characterized by X-ray photoelectron spectroscopy (XPS), which showed significant incorporation of nitrogen (N) and oxygen (O) at the materials’ surface. While high-resolution XP spectra did not yield much specific information about the incorporated functional groups, chemical derivatization with 4-trifluoromethyl benzaldehyde and trifluoroacetic anhydride accompanied by XPS enabled quantification of NH2 and OH groups, respectively. Using near edge X-ray absorption fine structure spectroscopy, we assessed the conservation of the aromatic structure following functionalization treatments. KW - Carbon nanotubes KW - Graphite KW - Vacuum ultraviolet photochemistry KW - Surface functionalization KW - Amino groups KW - Hydroxyl KW - Derivatization PY - 2012 U6 - https://doi.org/10.1016/j.apsusc.2012.03.012 SN - 0169-4332 SN - 1873-5584 VL - 258 IS - 22 SP - 8448 EP - 8454 PB - North-Holland CY - Amsterdam AN - OPUS4-26233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darlatt, Erik A1 - Nefedov, A. A1 - Traulsen, C.H.-H. A1 - Poppenberg, J. A1 - Richter, S. A1 - Dietrich, Paul A1 - Lippitz, Andreas A1 - Illgen, René A1 - Kühn, Julius A1 - Schalley, C.A. A1 - Wöll, Ch. A1 - Unger, Wolfgang T1 - Interperetation of experimental N K NEXAFS of azide, 1,2,3-triazole and terpyridyl groups by DFT spectrum simulations N2 - Experimental N K-edge NEXAFS data of surface immobilized azide, 1,2,3-triazole and terpyridyl groups are interpreted with the help of DFT spectrum simulations. Assignments of π* resonances in experimental N K-edge NEXAFS spectra to nitrogen atoms within these functional groups have been made. The azide was immobilized on gold as the head group of a thiol SAM, 1,2,3-triazole was formed on this SAM by click reaction and terpyridyl groups were introduced as substituents of the acetylene used for the click reaction. For azide-terminated molecules, DFT spectrum simulations are found to be useful to find measurement conditions delivering experimental N K-edge NEXAFS data with negligible X-ray damage. The 1,2,3-triazole group is found to be rather stable under X-ray irradiation. KW - N K-edge NEXAFS KW - XANES KW - Surface click chemistry KW - Density functional theory KW - Azide KW - 1,2,3-Triazole PY - 2012 U6 - https://doi.org/10.1016/j.elspec.2012.09.008 SN - 0368-2048 SN - 1873-2526 VL - 185 IS - 12 SP - 621 EP - 624 PB - Elsevier CY - Amsterdam AN - OPUS4-27774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tuaev, X. A1 - Paraknowitsch, J.P. A1 - Illgen, René A1 - Thomas, A. A1 - Strasser, P. T1 - Nitrogen-doped coatings on carbon nanotubes and their stabilizing effect on Pt nanoparticles N2 - A homogeneous coating of nitrogen-doped carbon on carbon nanotubes is performed using ionic liquids. The N-doped material is employed as a support for nanoparticles. Electrochemical degradation behavior is monitored in situ and compared to an unmodified material. The strongly enhanced stability is explained on the basis of a Pt–nitrogen interaction. PY - 2012 U6 - https://doi.org/10.1039/c2cp40760d SN - 1463-9076 SN - 1463-9084 VL - 14 IS - 18 SP - 6444 EP - 6447 PB - The Royal Soc. of Chemistry CY - Cambridge AN - OPUS4-25787 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -