Relationship Between the Local Structures of Titanium Oxide Photocatalysts and their Reactivities - XAFS, UV, Photoluminescence and Photoreaction Investigations
نویسندگان
چکیده
The liquid-phase photocatalytic oxidation of l-octanol in oxygenated acetoniaile on highly dispersed titanium oxide catalysts anchored onto transparent Vycor glass was compared with that obtained on the standard TiO2 powder. The isolated titanium oxide species anchored onto transparent Vycor glass are responsible for its high photocatalytic activity both in the present liquid-phase oxidation of I-octanol and in previously described gas-phase reactions. And also the photocatalytic degtadation of Zpropanol diluted in water was demonsuated on the titanium oxide catalysts highly dispersed onto Vycor glass which were prepared by Ti ions implantation method. The specific photocatalytic activity per unit weight of titanium oxide of the highly dispersed catalyst was much higher than that for the T i e powder. The photoluminescence, UV absorption and XAFS studies indicated that the charge transfer excited state of the highly dispersed isolated tetrahedral titanium oxide species play a significant mle in the liquid-phase photocatalytic reactions.
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