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Complejos divalentes de osmio: síntesis, caracterización, fosforescencia roja fuerte y electrofosforescencia
Brenden Carlson1, Gregory D Phelan, Werner Kaminsky
1Departments of Chemistry and Materials Science and Engineering, University of Washington, Seattle, WA 98195, USA.
Journal of the American Chemical Society
|November 21, 2002
Resumen
Los nuevos complejos de osmio divalente exhiben una fuerte fosforescencia roja y electrofosforescencia, logrando una alta eficiencia cuántica. Estos nuevos materiales se integraron con éxito en diodos orgánicos rojos emisores de luz (OLED) con un brillo impresionante y una emisión roja pura.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Inorgánica La Química Inorgánica es la química inorgánica.
- La fotoquímica es la fotoquímica.
Sus antecedentes:
- Los complejos de transferencia de carga de metal a ligando (MLCT) son cruciales para las aplicaciones optoelectrónicas.
- El desarrollo de materiales fosforescentes eficientes que emiten rojo sigue siendo un desafío importante.
Objetivo del estudio:
- Para sintetizar y caracterizar nuevos complejos divalentes de osmio con fuerte fosforescencia roja.
- Investigar el potencial de estos complejos en la fabricación de diodos orgánicos rojos emisores de luz (OLED).
Principales métodos:
- Síntesis de nuevos ligandos polipiridil y su coordinación con el osmio (II).
- Caracterización de las propiedades fotofísicas, incluida la emisión de fosforescencia y la eficiencia cuántica.
- Fabricación y prueba de dispositivos OLED de doble capa utilizando los complejos de osmio sintetizados.
Principales resultados:
- Los complejos de osmio mostraron una fuerte absorción MLCT y una emisión fosforescente roja (611-651 nm) con hasta un 45% de eficiencia cuántica.
- Los OLED fabricados lograron un brillo de más de 1400 cd/m2 con una tensión de encendido de 8 V.
- Los dispositivos exhibieron una emisión roja pura con coordenadas CIE (0.65, 0.34) y una eficiencia cuántica externa máxima del 0.64%.
Conclusiones:
- Los nuevos complejos divalentes de osmio son emisores rojos fosforescentes altamente eficientes.
- Estos complejos muestran una gran promesa para las aplicaciones en la tecnología OLED roja.
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