Comparison of sol-gel and solid-state prepared Eu2+ doped calcium aluminates

• Autorzy: Aitasalo T. , Hölsä J. , Jungner H. , Lastusaari M. , Niittykoski J.
• Konferencja: International Conference on Sol-Gel materials SGM 2001, Rokosowo, Poland
• Języki publikacji: EN

Abstrakty

EN

The Eu2+ doped calcium aluminate (CaAl2O4:Eu2+) was prepared by the sol-gel method. The structure and luminescence properties of the title compound were studied and compared to the corresponding properties of the materials prepared by a conventional solid state reaction. The use of the sol-gel method in preparation lowered the reaction threshold temperature by c.a. 200 ?C. An unusual hexagonal form of CaAl2O4:Eu2+, which cannot be prepared by the solid state reaction, was obtained by the sol-gel method. The UV excited luminescence and afterglow bands of the hexagonal CaAl2O4:Eu2+ were observed at a slightly longer wavelength than that of the normal monoclinic phase due to small differences in the crystal field effect on the splitting of the excited 4f65d1 configuration of the Eu2+ ion. The afterglow lifetime of the hexagonal phase was slightly longer than that of the monoclinic one due to deeper traps.

Słowa kluczowe

EN

Eu2+ doped calcium aluminate; sol-gel method; persistent luminescence

• Wydawca: Oficyna Wydawnicza Politechniki Wrocławskiej
• Czasopismo: Materials Science
• Rocznik: 2002
• Tom: Vol. 20, No. 1
• Strony: 15--20
• Opis fizyczny: Bibliogr. 15 poz.,

Twórcy

autor

Aitasalo T.

autor

Hölsä J.

autor

Jungner H.

autor

Lastusaari M.

autor

Niittykoski J.

• University of Turku, Department of Chemistry, FIN-20014 Turku, Finland