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Unravelling Site-Specific Photo-Reactions of Ethanol on Rutile TiO2(110).

ABSTRACT: Finding the active sites of catalysts and photo-catalysts is crucial for an improved fundamental understanding and the development of efficient catalytic systems. Here we have studied the photo-activated dehydrogenation of ethanol on reduced and oxidized rutile TiO2(110) in ultrahigh vacuum conditions. Utilizing scanning tunnelling microscopy, various spectroscopic techniques and theoretical calculations we found that the photo-reaction proceeds most efficiently when the reactants are adsorbed on regular Ti surface sites, whereas species that are strongly adsorbed at surface defects such as O vacancies and step edges show little reaction under reducing conditions. We propose that regular Ti surface sites are the most active sites in photo-reactions on TiO2.

SUBMITTER: Hansen JO

PROVIDER: S-EPMC4768110 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Unravelling Site-Specific Photo-Reactions of Ethanol on Rutile TiO2(110).

Hansen Jonas Ø JØ Bebensee Regine R Martinez Umberto U Porsgaard Soeren S Lira Estephania E Wei Yinying Y Lammich Lutz L Li Zheshen Z Idriss Hicham H Besenbacher Flemming F Hammer Bjørk B Wendt Stefan S

Scientific reports 20160226

Finding the active sites of catalysts and photo-catalysts is crucial for an improved fundamental understanding and the development of efficient catalytic systems. Here we have studied the photo-activated dehydrogenation of ethanol on reduced and oxidized rutile TiO2(110) in ultrahigh vacuum conditions. Utilizing scanning tunnelling microscopy, various spectroscopic techniques and theoretical calculations we found that the photo-reaction proceeds most efficiently when the reactants are adsorbed o ...[more]

PMID: 26915303

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