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Fuerte luminiscencia en el infrarrojo cercano en BaSnO3
Hiroshi Mizoguchi1, Patrick M Woodward, Cheol-Hee Park
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210-1185, USA.
Journal of the American Chemical Society
|August 5, 2004
Resumen
El óxido de estaño de bario (BaSnO3) muestra una fuerte luminiscencia en el infrarrojo cercano (NIR) a temperatura ambiente debido a los estados de defecto. Esta propiedad única puede derivarse de la recombinación de agujero de electrones que involucra un nivel de donante Sn2+).
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física del estado sólido Física del estado sólido
- La luminiscencia es la luminiscencia.
Sus antecedentes:
- El estanato de bario (BaSnO3) es un material de perovskita con aplicaciones potenciales en la optoelectrónica.
- Comprender sus propiedades de fotoluminiscencia es crucial para el diseño de materiales y el desarrollo de dispositivos.
Objetivo del estudio:
- Para investigar la luminiscencia del infrarrojo cercano (NIR) y visible de BaSnO3 a temperatura ambiente y baja.
- Para explorar el efecto de la sustitución de estroncio en las características de fotoluminiscencia de Ba{1-x) Sr{x) SnO3.3.
Principales métodos:
- Espectroscopia de difracción y fotoluminiscencia (PL) de rayos X en polvo.
- Mediciones de espectros de excitación y emisión a temperatura ambiente (RT) y 77 K.
- Análisis de las vidas de luminiscencia y los desplazamientos de Stokes.
Principales resultados:
- Fuerte emisión NIR centrada en 905 nm con un gran desplazamiento de Stokes de 1.9 eV observado en BaSnO3 en RT.
- Las vidas de luminiscencia (7-18 ms) sugieren la participación de estados de defecto.
- La emisión visible aparece a bajas temperaturas, aumentando a medida que disminuye la intensidad de la emisión NIR.
- La sustitución de estroncio desplaza la brecha de banda y la emisión NIR, aumentando el desplazamiento de Stokes.
Conclusiones:
- La inusual fotoluminiscencia NIR en BaSnO3 probablemente se origina en la recombinación de agujeros fotogenerados con un nivel de donante ocupado asociado con Sn2+).
- Los estados de defecto juegan un papel importante en las propiedades de luminiscencia observadas.
- El ajuste del contenido de estroncio ofrece una vía para modificar las propiedades optoelectrónicas de Ba{1-x) Sr{x) SnO3.3.
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