Improved charge carrier separation in barium tantalate composites investigated by laser flash photolysis

Show simple item record

dc.identifier.uri http://dx.doi.org/10.15488/223
dc.identifier.uri http://www.repo.uni-hannover.de/handle/123456789/245
dc.contributor.author Schneider, Jenny ger
dc.contributor.author Nikitin, Konstantin ger
dc.contributor.author Wark, Michael ger
dc.contributor.author Bahnemann, Detlef W. ger
dc.contributor.author Marschall, Roland ger
dc.date.accessioned 2016-02-23T13:47:00Z
dc.date.available 2016-02-23T13:47:00Z
dc.date.issued 2015-12-15
dc.identifier.citation Schneider, Jenny; Nikitin, Konstantin; Wark, Michael; Bahnemann, Detlef W.; Marschall, Roland: Improved charge carrier separation in barium tantalate composites investigated by laser flash photolysis. In: Physical Chemistry Chemical Physics 2016. DOI: http://dx.doi.org/10.1039/c5cp07115a
dc.description.abstract Charge carrier dynamics in phase pure Ba5Ta4O15 and in a Ba5Ta4O15–Ba3Ta5O15 composite have been studied by means of diffuse reflectance laser flash photolysis spectroscopy in the presence and absence of an electron donor, in order to reveal the reason for the improved photocatalytic performance of the latter. For the first time the transient absorption of trapped electrons with a maximum at around 650 nm and of trapped holes with a transient absorption maximum at around 310 nm is reported for tantalates. The decay kinetics of the photogenerated charge carriers could be fitted by second order reaction kinetics, and the direct recombination of the trapped electrons with the trapped holes was proven. In the absence of an electron donor, no difference in the decay behavior between the phase pure material and the composite material is found. In the presence of methanol, for the pure phase Ba5Ta4O15 the recombination of the charge carriers could not be prevented and the trapped electrons also recombine with the ˙CH2OH radical formed via the methanol oxidation by the trapped holes. However, in the composite, the electron can be stored in the system, the ˙CH2OH radical injects an electron into the conduction band of the second component of the composite, i.e., Ba3Ta5O15. Thus, the electrons are available for an extended period to induce reduction reactions. eng
dc.language.iso eng eng
dc.publisher Cambridge : Royal Society of Chemistry
dc.relation.ispartofseries Physical Chemistry Chemical Physics (2016)
dc.rights CC BY-NC 3.0 Unported
dc.rights.uri http://creativecommons.org/licenses/by-nc/3.0/ ger
dc.subject charge carrier separation eng
dc.subject laser flash photolysis eng
dc.subject barium tantalate eng
dc.subject Ba5Ta4O15 eng
dc.subject Ba3Ta5O15 eng
dc.subject Ladungsträgertrennung ger
dc.subject Laser-Blitzphotolyse ger
dc.subject Barium ger
dc.subject Bariumtantalate ger
dc.subject Ba5Ta4O15 ger
dc.subject Ba3Ta5O15 ger
dc.subject.ddc 540 | Chemie ger
dc.subject.ddc 530 | Physik ger
dc.title Improved charge carrier separation in barium tantalate composites investigated by laser flash photolysis eng
dc.type article
dc.type Text
dc.relation.essn 1463-9084
dc.relation.issn 1463-9076
dc.relation.doi http://dx.doi.org/10.1039/c5cp07115a
dc.description.version publishedVersion
tib.accessRights frei zug�nglich


Files in this item

This item appears in the following Collection(s):

Show simple item record

 

Search the repository


Browse

My Account

Usage Statistics