TY - JOUR
T1 - Interaction of dimethylamine with clean and partially oxidized copper surfaces
AU - Kelber, J. A.
AU - Rogers, J. W.
AU - Banse, B. A.
AU - Koel, Bruce E.
N1 - Funding Information:
This work was supported in part (J.E.K. and J.W.R.) by the United States Department of Energy under contract DE-AC04-76DP00789. B.E.K. acknowledges partial support of this work by the United States Department of Energy, Office of Basic Energy Sciences, Chemical Sciences Division. The authors would like to thank Dr. Tom Taylor of Los Alamos National Laboratory for loan of the Cu(ll0) single crystal.
PY - 1990/5
Y1 - 1990/5
N2 - The interaction of dimethylamine (DMA) with partially oxidized polycrystalline copper [Cu(poly)] and clean and partially oxidized Cu(110) between 110 and 500 K has been examined using electron stimulated desorption (ESD), high resolution electron energy loss spectroscopy (HREELS) and temperature programmed desorption (TPD). ESD mass spectra of the DMA adsorbed on O/Cu(poly) between 112 and 230 K consistently display peaks at 44 amu [(CH3)2N]+ and 46 amu [(CH3)2NH-H]+, but no significant parent peak at 45 amu [(CH3)2NH]+, even though this last feature is prominent in the gas-phase mass spectrum. OH- is not observed at temperatures below 184 K and the yield at higher temperatures is much less than that of O+. HREELS of DMA on clean and oxygen covered Cu(110) obtained at temperatures between 100 and 320 K show characteristic vibrational spectra for molecular DMA and no OH(a) vibrational modes. TPD results show that the desorption profiles of all the major peaks in the DMA mass spectrum follow that of the parent peak with no evidence for production of H2O. The ESD, HREELS and TPD results all indicate that DMA is molecularly and reversibly adsorbed, with no significant formation of surface hydroxyl species. The results indicate that preferential adsorption of amines from amine/epoxy mixtures onto metal oxide surfaces could passivate the surface and prevent subsequent bonding to the epoxy resin.
AB - The interaction of dimethylamine (DMA) with partially oxidized polycrystalline copper [Cu(poly)] and clean and partially oxidized Cu(110) between 110 and 500 K has been examined using electron stimulated desorption (ESD), high resolution electron energy loss spectroscopy (HREELS) and temperature programmed desorption (TPD). ESD mass spectra of the DMA adsorbed on O/Cu(poly) between 112 and 230 K consistently display peaks at 44 amu [(CH3)2N]+ and 46 amu [(CH3)2NH-H]+, but no significant parent peak at 45 amu [(CH3)2NH]+, even though this last feature is prominent in the gas-phase mass spectrum. OH- is not observed at temperatures below 184 K and the yield at higher temperatures is much less than that of O+. HREELS of DMA on clean and oxygen covered Cu(110) obtained at temperatures between 100 and 320 K show characteristic vibrational spectra for molecular DMA and no OH(a) vibrational modes. TPD results show that the desorption profiles of all the major peaks in the DMA mass spectrum follow that of the parent peak with no evidence for production of H2O. The ESD, HREELS and TPD results all indicate that DMA is molecularly and reversibly adsorbed, with no significant formation of surface hydroxyl species. The results indicate that preferential adsorption of amines from amine/epoxy mixtures onto metal oxide surfaces could passivate the surface and prevent subsequent bonding to the epoxy resin.
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U2 - 10.1016/0169-4332(90)90050-A
DO - 10.1016/0169-4332(90)90050-A
M3 - Article
AN - SCOPUS:0025431931
SN - 0169-4332
VL - 44
SP - 193
EP - 204
JO - Applied Surface Science
JF - Applied Surface Science
IS - 3
ER -