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Conversión ascendente de sensibilización cooperativa de Yb a Eu en un grupo de lantánidos no nucleares moleculares
Sai P K Panguluri1, Elsa Jourdain2, Papri Chakraborty3
1Institute of Quantum Materials and Technologies (IQMT), Karlsruhe Institute of Technology, Kaiserstraße 12, Karlsruhe 76311, Germany.
Journal of the American Chemical Society
|May 3, 2024
Resumen
Este estudio informa de un nuevo cúmulo de lantánidos que exhibe una luminiscencia de conversión hacia arriba eficiente y actúa como un imán de una sola molécula. Esta doble funcionalidad abre las puertas para dispositivos moleculares avanzados.
Área de la Ciencia:
- Química de coordinación
- Ciencias de los materiales
- La fotofísica
Sus antecedentes:
- Los clústeres de metales lantánidos conectan la química molecular y la química de los materiales.
- La luminiscencia de conversión hacia arriba (UC) y el magnetismo de una sola molécula (SMM) son propiedades clave para los materiales avanzados.
Objetivo del estudio:
- Sintetizar y caracterizar un grupo de lantánidos heteronucleares con propiedades cooperativas de sensibilización UC.
- Para investigar la luminiscencia y el comportamiento magnético del grupo [Eu8Yb(BA) 16 ((OH) 10).
Principales métodos:
- Síntesis y caracterización del grupo no nuclear Eu3+/Yb3+ en estado sólido y en solución.
- Análisis espectroscópico para observar la luminiscencia UC y la emisión desplazada hacia abajo.
- Mediciones de la susceptibilidad magnética para determinar las propiedades de los SMM.
Principales resultados:
- Fenómeno de sensibilización cooperativa UC observado con emisión visible de Eu3+ tras la excitación de Yb3+ por NIR a bajas concentraciones (100 nM).
- El rendimiento cuántico es de 4,88 × 10-8 para la luminiscencia UC.
- Emisión NIR desplazada hacia abajo de Yb3+ tras la excitación visible de Eu3+.
- La luminiscencia cooperativa de Yb3+ se observa alrededor de los 500 nm.
- El cúmulo exhibe un comportamiento de imán de una sola molécula inducido por el campo a 4K.
Conclusiones:
- El grupo [Eu8Yb(BA) 16 ((OH) 10) Cl demuestra propiedades eficientes de luminiscencia UC y SMM.
- Este grupo heteronuclear sirve como prototipo para dispositivos de próxima generación que integran luminiscencia y magnetismo.
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