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Los silicatos de lantánidos en capas fotoluminiscentes también son fotoluminiscentes.
Duarte Ananias1, Mariya Kostova, Filipe A Almeida Paz
1Contribution from the Department of Chemistry, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal.
Journal of the American Chemical Society
|August 19, 2004
Resumen
Se sintetizaron y caracterizaron nuevos silicatos lantánidos en capas (materiales AV-22). Estos materiales exhiben fotoluminiscencia sintonizable, con aplicaciones potenciales como fósforos en tecnologías de iluminación.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- Química del estado sólido.
Sus antecedentes:
- Los silicatos de lantanuro son una clase de materiales con interesantes propiedades ópticas.
- El desarrollo de nuevos fósforos con emisión ajustable es crucial para las aplicaciones avanzadas de iluminación.
Objetivo del estudio:
- Para sintetizar hidrotermalmente y caracterizar estructuralmente los nuevos silicatos lantánidos en capas, designados AV-22.2.
- Para investigar las propiedades fotoluminiscentes de estos materiales AV-22 dopados con varios iones lantánidos.
Principales métodos:
- Difracción de rayos X monocristalino y en polvo para elucidación estructural.
- Análisis químico, termogravimetría, SEM, (29) Si MAS RMN y espectroscopia de fotoluminiscencia para la caracterización.
- Técnica de síntesis hidrotermal.
Principales resultados:
- Se ha logrado la síntesis exitosa de los materiales K(3) [M(1-a) Ln(a) Si(3) O(8) (OH) ((2) ] (AV-22).
- El Er-AV-22 funciona como un fósforo infrarrojo a temperatura ambiente.
- Tb- y Eu-AV-22 exhiben emisiones visibles con eficiencias comparables a las normas comerciales.
- Fotoluminiscencia sintonizable lograda mediante la incorporación de múltiples iones lantánidos.
- Pruebas de la transferencia de energía de Tb(3+) a Eu(3+) en materiales mezclados dopados.
Conclusiones:
- La estructura de AV-22 en capas facilita la incorporación de múltiples iones lantánidos para una luminiscencia de ajuste fino.
- Estos materiales son prometedores para aplicaciones en tecnologías de iluminación y visualización.
- Se observaron mecanismos eficientes de transferencia de energía en materiales AV-22 co-dopados.
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