Temperature programmed desorption study of pre-irradiated TiO2 anatase in the presence of ethanol. Effect of conduction band electrons on reaction selectivity
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引用次数: 0
Abstract
The work addresses one of the fundamentals of photocatalytic reactions, the fate of conduction-band (CB) electrons of a photo-excited TiO2-anatase. Some of these CB-electrons are self-trapped as large-polarons. We have studied by Infrared-spectroscopy these polarons upon UV-excitation in the presence and absence of O2. Moreover, the effect of CB-electrons on chemical reactions was investigated by temperature-programmed-desorption. Over the non-irradiated TiO2, the dehydration and oxidation products dominated, while over that prior UV-irradiated in the presence of ethanol the dehydrogenation product increased and the oxidation pathway was partly suppressed. These changes are attributed to CB-electrons that made the near-surface more metallic.
期刊介绍:
Chemical Physics Letters has an open access mirror journal, Chemical Physics Letters: X, sharing the same aims and scope, editorial team, submission system and rigorous peer review.
Chemical Physics Letters publishes brief reports on molecules, interfaces, condensed phases, nanomaterials and nanostructures, polymers, biomolecular systems, and energy conversion and storage.
Criteria for publication are quality, urgency and impact. Further, experimental results reported in the journal have direct relevance for theory, and theoretical developments or non-routine computations relate directly to experiment. Manuscripts must satisfy these criteria and should not be minor extensions of previous work.