Natzeck, C.

Nefedov, A.

Sezen, H.

Wöll, C.

English

KITopen

KIT – Universität des Landes Baden-Württemberg undnationales Forschungszentrum in der Helmholtz-Gemeinschaft472 464 456r-Ti(110)Ti2+Ti3+Sputtered  Intensity (a.u.)Binding Energy (eV)AnnealedTi2pTi4+oxidation state4000 3000 2000 100011159403680970Treatments:r-TiO2 powderTs: 300 K0.001 UV atomic hydrogenAbsorbanceWavenumber (cm^-1)  continuumConductionBandHikmet Sezen, Carsten Natzeck, Alexei Nefedov, Christof WöllInstitute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany1.) M. Xu, Y. Gao, E. M. Moreno, M. Kunst, M. Muhler, Y. Wang, H. Idriss, C. Wöll,Phys. Rev. Lett. 106, 138302 (2011).2.) M. Xu, H. Noei, K. Fink, M. Muhler, Y. Wang, C. Wöll, Angew. Chem. Int. Ed. 51,4731 (2012)3.) C. Di Valentin, G. Pacchioni, A. Selloni, J. of Phys. Chem. C 113, 20543 (2009)4.) D. M. Savory, D. S. Warren, A. J. McQuillan, J. Phys. Chem. C 115, 902 (2010).5.) D. A. Panayotov and J. T. Yates Jr, Che. Phys. Lett. 436, 204 (2007).6.) D. A. Panayotov, S. P. Burrows, J. R. Morris, J. Phys. Chem. C 116, 4535 (2012).Probing trapped shallow state electrons delivering from bothatomic hydrogen and UV treatments on powder and single crystalTiO2 samples by a novel method of the infrared reflectionabsorption spectroscopy in an ultrahigh vacuum environment(UHV-IRRAS).[1-2] However, now we have a more furnished UHVsystem at KIT, which is called as THEO!Sample Preparation:UHV-IRRAS and -FTIRBruker Vertex 80vPreparation chamber with LEED, AES, TDS,and effussion cells. LoadlockLoadlockMagazinesecond prep.chamberreflectionXPS:XPS, UPS, AES AnalyzerVG Scienta R4000LEED:rutile TiO2(110)surface crystal structure 290 280C1s    Binding Energy (eV)Intensity (a.u.) Before sputtering After sputteringcleannessScopeInstrumentalExperimentResultsReferencesUHV-FTIRUHV-IRRASpowderscrystalsingleCryostat for LHe cooling9 6 3 0 -3 (HeI)Annealing Sputtered AnnealedTi+3 3dO 2p Valence Band    Intensity (a.u.)Binding Energy (eV)TiO2 UPS: defect state3 2 1 0 -1AnnealingTi3+ 3dIntensity (a.u.)    Binding Energy (eV)transmissionTransmission sample holder:ΔT: 1200K-100K (LHe 30K)E-beam sample holder:ΔT: 1500K-100K (LHe 30K)Efe-UVValanceBandshallow trapsIRh+OTiTiH•donorstate(i)(ii)(a) donation or (b) localization4000 3000 2000 1000 UV atomic hydrogenTreatments:910121013703730 3215372532151205r-TiO2(110)    AbsorbanceWavenumber (cm^-1)0.0005Ts: 300 K910(c) probingPerformance of the system: CO absorption on r-TiO2[2]ΔEexcitationSingle Crystals: Powders:ΔE (eV)Experimental 0.11 – 0.15 Anatase bulk [3] 0.3Rutile ?OTi3+Oas polaronD.A. Panayotov, J.T. Yates Chem. Phys. Lett. 436, 204 (2007) 3900 3600 3300 300032153725    x10

Shallow trapped electron states and related processes of TiO₂ probing with UHV-IRRAS

https://publikationen.bibliothek.kit.edu/220094746/3816483

Shallow trapped electron states and related processes of TiO₂ probing with UHV-IRRAS

Abstract

Similar works

Full text

Available Versions

KITopen