کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5426296 | 1395886 | 2007 | 6 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Soft X-ray appearance potential spectroscopy (SXAPS) study of TiO2(1 1 0)-1 Ã 2 and (0 0 1)-1 Ã 1 surfaces Soft X-ray appearance potential spectroscopy (SXAPS) study of TiO2(1 1 0)-1 Ã 2 and (0 0 1)-1 Ã 1 surfaces](/preview/png/5426296.png)
A soft X-ray appearance potential spectroscopy (SXAPS) apparatus with high sensitivity was built to measure non-derivative spectra. SXAPS spectra (non-derivative) of Ti 2p and O 1s for TiO2(1 1 0)-1 Ã 2 and (0 0 1)-1 Ã 1 surfaces have been measured using low incident currents (about 10 μA/cm2) and a photon counting mode. Density of empty states on Ti and O sites are deduced by self-deconvoluting the spectra. The self-deconvoluted SXAPS spectra are qualitatively similar to those measured by X-ray absorption spectroscopy (XAS). The Ti 2p3/2 spectrum shows two strong peaks which correspond to t2g and eg states. For the O 1s spectrum two strong peaks near the threshold are also found which can be ascribed to O 2pÏ and O 2pÏ states. These results suggest that the spectra almost obey the dipole selection rule, so-called the “approximate dipole selection rule”. The SXAPS spectra of Ti 2p and O 1s for the (1 1 0) and (0 0 1) surfaces resemble qualitatively, which is consistent with the XAS results. The spectra measured on the (1 1 0)-1 Ã 2 surface at an incident angle of 45° off normal to the surface and on the (1 1 0) surface sputtered by Ar ions indicate that SXAPS is very sensitive to the surface electronic states.
Journal: Surface Science - Volume 601, Issue 23, 1 December 2007, Pages 5320-5325