The adsorption of ethanol on Si(100)2x1 has been investigated at room temperature by high-resolution synchrotron radiation photoemission, and a consistent picture has been obtained in favour of dissociative adsorption, rom a comparison of the valence band for pure and adsorbed ethanol, which shows the disappearance of sigma(O-H) orbital after adsorption, and from the identification of a Si-O-related component in the Si 2p core spectrum. A lineshape analysis of the Si 2p complex envelope corresponding to different ethanol exposures identifies a second component, which grows with the exposure at a different rate, and is assigned to Si-H bond. The values for relative quantitative ratios among the various components suggest an exposure-dependent adsorption mechanism for ethanol, characterized by the formation of stable Si-O bonds and a high hydrogen surface mobility. The analysis of the C 1s photoemission core-line suggests that no C-O bond rupture occurs, at variance with our previous findings for ethanol adsorption on Si(111)7x7. (C) 2000 Published by Elsevier Science B.V. All rights reserved.
Casaletto, M., Zanoni, R., Carbone, M., Piancastelli, M., Aballe, L., Weiss, K., et al. (2000). High-resolution photoemission study of ethanol on Si(100)2 x 1. SURFACE SCIENCE, 447(1), 237-244 [10.1016/S0039-6028(99)01197-8].
High-resolution photoemission study of ethanol on Si(100)2 x 1
CARBONE, MARILENA;
2000-01-01
Abstract
The adsorption of ethanol on Si(100)2x1 has been investigated at room temperature by high-resolution synchrotron radiation photoemission, and a consistent picture has been obtained in favour of dissociative adsorption, rom a comparison of the valence band for pure and adsorbed ethanol, which shows the disappearance of sigma(O-H) orbital after adsorption, and from the identification of a Si-O-related component in the Si 2p core spectrum. A lineshape analysis of the Si 2p complex envelope corresponding to different ethanol exposures identifies a second component, which grows with the exposure at a different rate, and is assigned to Si-H bond. The values for relative quantitative ratios among the various components suggest an exposure-dependent adsorption mechanism for ethanol, characterized by the formation of stable Si-O bonds and a high hydrogen surface mobility. The analysis of the C 1s photoemission core-line suggests that no C-O bond rupture occurs, at variance with our previous findings for ethanol adsorption on Si(111)7x7. (C) 2000 Published by Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
