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surface:research:tio2 [2014-03-06 09:54]
Michael Schmid Phys. Rev. links fixed
surface:research:tio2 [2014-03-12 14:02] (current)
Michael Schmid more on O2/anatase
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Whereas O<sub>2</sub> dissociates in a rather benign manner, dissociation of the chlorine molecule is a more hefty process: Already a decade ago, we have found evidence that Cl<sub>2</sub> adsorbed on rutile TiO<sub>2</sub>(110) literally explodes, and the the Cl atoms fly apart by 26 Å, a long distance on the atomic scale. Whereas O<sub>2</sub> dissociates in a rather benign manner, dissociation of the chlorine molecule is a more hefty process: Already a decade ago, we have found evidence that Cl<sub>2</sub> adsorbed on rutile TiO<sub>2</sub>(110) literally explodes, and the the Cl atoms fly apart by 26 Å, a long distance on the atomic scale.
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-We have recently studied oxygen adsorption on an anatase surface: In contrast to rutile, the anatase TiO<sub>2</sub>(101) surface has no oxygen vacancies on the surface but below, so it's all different. You will read more about it soon.<clear>+
===== Organic molecules ===== ===== Organic molecules =====
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===== Anatase ===== ===== Anatase =====
-TiO<sub>2</sub> comes in three different crystalline forms, rutile, anatase and brookite. Rutile is the stable form for macroscopic crystals, and therefore most of the previous work on TiO<sub>2</sub>, including everything described above, was on rutile surfaces. In practical applications, nanometer-sized crystals are often anatase; we have therefore started to study its surfaces. In contrast to rutile, the anatase TiO<sub>2</sub>(101) surface usually has no oxygen vacancies on the surface but below, so it's all different!+TiO<sub>2</sub> comes in three different crystalline forms, rutile, anatase and brookite. Rutile is the stable form for macroscopic crystals, and therefore most of the previous work on TiO<sub>2</sub>, including everything described above, was on rutile surfaces. In practical applications, nanometer-sized crystals are often anatase; we have therefore started to study its surfaces. In contrast to rutile, the anatase TiO<sub>2</sub>(101) surface usually has no stable oxygen vacancies on the surface: O vacancies are below, so it's all different! Nevertheless, O<sub>2</sub> adsorbed at the surface can interact with an O vacancy, and then a O<sub>2</sub><sup>2-</sup> (peroxo) species may replace an oxygen atom in the surface.  See our papers (listed below) for details. 
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surface/research/tio2.1394096092.txt.gz · Last modified: 2014-03-06 09:54 by Michael Schmid