AI Article Synopsis
- * When fluorine is adsorbed, it weakens Ti-O bonds on the (101) surface but strengthens them on the (001) surface, making (001) more stable with fluorine present.
- * The research highlights that n-type doping can reduce the impact of fluorine on the stability of these surfaces, offering insights into the properties of TiO2 and suggesting methods to create samples with a high amount of the (001) structure.
Article Abstract
The stability of both the pure and fluorine (F)-adsorbed surface of TiO2 is examined on the basis of density functional calculations. For pure surfaces, both the beneficial local geometric structures and local potential strengthen the Ti-O binding in (101), rendering it the most stable surface. For F-adsorbed surfaces, F-adsorption significantly weakens the Ti-O bonds in (101) but strengthens them in (001), so that (001) becomes more stable than (101) for the F-adsorbed surfaces. On the basis of this observation, we further show that the n-type doping in TiO2 can significantly decrease the ability of F-adsorption in switching the relative stability of the two surfaces. The present work not only provides new insights into the physical and chemical properties about both pure and F-adsorbed surfaces of TiO2 and conclusively explains related experimental results but also suggests viable ways to prepare TiO2 samples with a high percentage of (001).
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| http://dx.doi.org/10.1021/acs.jpclett.5b00595 | DOI Listing |
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