title: Photoluminescent layered Y(III) and Tb(III) silicates doped with Ce(III).
abstract: The synthesis and structural characterization of new layered rare-earth silicates K(3)[M(1-a)Ce(a)Si(3)O(8)(OH)(2)], M = Y(3+), Tb(3+), a << 1 (AV-22 materials), have been reported. These materials combine the properties of layered silicates, such as intercalation chemistry, and photoluminescence and may find applications in new types of sensor devices. For mixed Tb/Ce-AV-22, evidence has been found for the energy transfer from the large Ce(3+) 4f( 1) --> 5d(1) broad band to the sharp Tb(3+) 4f (8) lines. This energy transfer allows the fine-tuning of the color emission in the blue-green region of the chromaticity diagram. Upon Ce(3+) excitation (342 nm), the radiance of Tb/Ce-AV-22 is approximately 2 times higher than that measured under direct Tb(3+) excitation, which reinforces the existence of effective room-temperature Ce(3+)-to-Tb(3+) energy transfer.
authors.affiliation: Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Mariya H
authors.initials: MH
authors.lastname: Kostova
authors.forename: Rute A
authors.initials: RA
authors.lastname: Sá Ferreira
authors.forename: Duarte
authors.initials: D
authors.lastname: Ananias
authors.forename: Luís D
authors.initials: LD
authors.lastname: Carlos
authors.forename: João
authors.initials: J
authors.lastname: Rocha
mesh_terms: D002563:Cerium / Q000737:chemistry*; D049449:Luminescence; D010777:Photochemistry; D017640:Silicates / Q000737:chemistry*; D013725:Terbium / Q000737:chemistry*; D013997:Time Factors; D015019:Yttrium / Q000737:chemistry*
chemical_list: D017640:Silicates; D013725:Terbium; D002563:Cerium; C028301:yttrium silicate; D015019:Yttrium