TU Darmstadt / ULB / TUbiblio

Influence of oxygen doping and hydration on photostimulated luminescence of CsBr and CsBr:Eu2+

Appleby, G. A. ; Kroeber, P. ; Zimmermann, J. ; Seggern, H. von (2011)
Influence of oxygen doping and hydration on photostimulated luminescence of CsBr and CsBr:Eu2+.
In: Journal of Applied Physics, 109 (7)
doi: 10.1063/1.3569745
Artikel, Bibliographie

Kurzbeschreibung (Abstract)

Powdered samples of CsBr:O2− and CsBr:Eu2+,O2− with oxygen concentrations ranging from 0.01 to 5.00 mol% have been synthesized and are shown to have photostimulated luminescence (PSL) properties which are strongly influenced by the oxygen concentration. In europium free CsBr:O2−, it was found that weak PSL emission at 460 nm arises from oxygen impurities while with oxygen concentrations higher than 0.05 mol% the emission shifts to the 379 nm emission of the CsBr matrix, which is attributed to the nonexcitability of oxygen agglomerates. The F-center concentration in CsBr:O2− is observed to increase with oxygen concentration, due to an increase in Br-vacancies as charge compensation centers for the O2− ions. In all CsBr:Eu2+ samples studied, intense PSL emission arises only following room temperature hydration in an atmosphere of 99% relative humidity, and it is concluded that the presence of water molecules is essential for the PSL in CsBr:Eu2+. In CsBr:Eu2+,O2− this enhancement effect of PSL intensity is reduced as the oxygen concentration increases above 0.05 mol% due to competition between the Eu2+ and O2− luminescence centers. It was found that the effects of hydration can be partially reversed following exposure to a vacuum while the material is rendered completely PSL inactive following thermal annealing up to 600 °C which is caused by agglomeration of the highly mobile Eu2+ ions and subsequent loss of Eu2+ luminescence.

Typ des Eintrags: Artikel
Erschienen: 2011
Autor(en): Appleby, G. A. ; Kroeber, P. ; Zimmermann, J. ; Seggern, H. von
Art des Eintrags: Bibliographie
Titel: Influence of oxygen doping and hydration on photostimulated luminescence of CsBr and CsBr:Eu2+
Sprache: Englisch
Publikationsjahr: 1 April 2011
Verlag: AIP Publishing LLC
Titel der Zeitschrift, Zeitung oder Schriftenreihe: Journal of Applied Physics
Jahrgang/Volume einer Zeitschrift: 109
(Heft-)Nummer: 7
DOI: 10.1063/1.3569745
Kurzbeschreibung (Abstract):

Powdered samples of CsBr:O2− and CsBr:Eu2+,O2− with oxygen concentrations ranging from 0.01 to 5.00 mol% have been synthesized and are shown to have photostimulated luminescence (PSL) properties which are strongly influenced by the oxygen concentration. In europium free CsBr:O2−, it was found that weak PSL emission at 460 nm arises from oxygen impurities while with oxygen concentrations higher than 0.05 mol% the emission shifts to the 379 nm emission of the CsBr matrix, which is attributed to the nonexcitability of oxygen agglomerates. The F-center concentration in CsBr:O2− is observed to increase with oxygen concentration, due to an increase in Br-vacancies as charge compensation centers for the O2− ions. In all CsBr:Eu2+ samples studied, intense PSL emission arises only following room temperature hydration in an atmosphere of 99% relative humidity, and it is concluded that the presence of water molecules is essential for the PSL in CsBr:Eu2+. In CsBr:Eu2+,O2− this enhancement effect of PSL intensity is reduced as the oxygen concentration increases above 0.05 mol% due to competition between the Eu2+ and O2− luminescence centers. It was found that the effects of hydration can be partially reversed following exposure to a vacuum while the material is rendered completely PSL inactive following thermal annealing up to 600 °C which is caused by agglomeration of the highly mobile Eu2+ ions and subsequent loss of Eu2+ luminescence.

Freie Schlagworte: annealing, caesium compounds, charge compensation, doping profiles, europium, F-centres, impurities, oxygen, photoluminescence, powders, solvation, vacancies (crystal)
Fachbereich(e)/-gebiet(e): 11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft > Elektronische Materialeigenschaften
11 Fachbereich Material- und Geowissenschaften > Materialwissenschaft
11 Fachbereich Material- und Geowissenschaften
Hinterlegungsdatum: 14 Okt 2013 09:18
Letzte Änderung: 14 Okt 2013 09:18
PPN:
Sponsoren: The authors would like to acknowledge financial support from the Deutsche Forschungsgemeinschaft (DFG).
Export:
Suche nach Titel in: TUfind oder in Google
Frage zum Eintrag Frage zum Eintrag

Optionen (nur für Redakteure)
Redaktionelle Details anzeigen Redaktionelle Details anzeigen