Valence band and surface core-level shift studies of the oxygen-induced p(3 × 1) reconstruction of the W(1 0 0) surface |
| |
Authors: | N. Moslemzadeh S.D. Barrett |
| |
Affiliation: | a Surface Science Research Centre, University of Liverpool, P.O. Box 147, Liverpool L69 3BX, UK b Surface Analysis Laboratory, School of Engineering, University of Surrey, Guilford, Surrey GU2 7XH, UK c Department of Physics, University of Liverpool, P.O. Box 147, Liverpool L69 7ZE, UK |
| |
Abstract: | Using synchrotron radiation, W 4f7/2 and valence-band (VB) photoelectron spectroscopy was used to study the oxidation states of the p(3 × 1) reconstructed surface of W(1 0 0) produced by oxygen adsorption at 1500 K. The W 4f7/2 study showed two features at 0.40 and 1.50 eV higher binding energies relative to the bulk feature which represent shifts to lower binding energies compared to the W 4f7/2 features of the as-grown oxygen films on W(1 0 0). Co-existence of these features is a characteristic of the formation of the p(3 × 1) structure. The VB studies of this system and as-grown oxygen films at room temperature (RT) showed an oxygen-induced feature for the p(3 × 1) structure for which the peak maximum had shifted by 0.9 eV to higher binding energies compared to the as-grown films. The direction of shifts in the W 4f7/2 and VB spectra for the p(3 × 1) structure confirmed the reduction of the charge transfer from W to oxygen compared to the as-grown films. A study of the VB changes with photon energy shows that the main component of the oxygen-induced feature in the p(3 × 1) VB at 6.6 ± 0.2 eV is related to a hybridized state between W 5d and O 2p electrons. |
| |
Keywords: | Tungsten Tungsten oxide Photoemission |
本文献已被 ScienceDirect 等数据库收录! |
|