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El control del pH de la transferencia de energía intramolecular y el apagado del oxígeno en los complejos Ru (II) que
Tod A Grusenmeyer1, Jin Chen, Yuhuan Jin
1Department of Chemistry, Tulane University, New Orleans, Louisiana 70118, USA.
Journal of the American Chemical Society
|April 3, 2012
Resumen
Este estudio demuestra el control del pH sobre la transferencia de energía del estado excitado en complejos de rutenio. Al ajustar el pH, los investigadores pueden ajustar los niveles de energía, mejorando el desarrollo del sensor de oxígeno luminiscente.
Área de la Ciencia:
- La fotoquímica y la fotofísica.
- Coordinación Química de la Coordinación
- Ciencia de los materiales Ciencia de los materiales.
Sus antecedentes:
- Los complejos de metales de transición ofrecen propiedades fotofísicas sintonizables.
- Los procesos de transferencia de energía son cruciales en los sistemas moleculares.
- Los ligandos sensibles al pH pueden modular los estados electrónicos.
Objetivo del estudio:
- Para ilustrar el control del pH sobre la transferencia de energía del estado excitado en los complejos Ru(II).
- Investigar la relación entre el pH, los niveles de energía y la vida útil del estado excitado.
- Explorar el potencial para el desarrollo de sensores luminiscentes de oxígeno.
Principales métodos:
- Síntesis de complejos de Ru (II) vinculados al pireno a través de los ligandos de bipiridil.
- Utilizando la variación del pH para alterar la energía del estado (3) MLCT.
- Empleando espectroscopia ultrarrápida y de resolución temporal de microsegundos para analizar las desintegraciones en estado excitado.
Principales resultados:
- La energía del estado Ru(II) a carboxi-bipiridina (3)MLCT es dependiente del pH.
- El aumento del pH conduce a un aumento de la energía de estado (3) MLCT, aumentando la vida útil de la emisión de 2 μs a >10 μs.
- La extinción del estado excitado por el oxígeno muestra una dependencia del pH que refleja la vida útil del estado excitado.
Conclusiones:
- Los equilibrios de estado excitado pueden ser controlados eficazmente por el pH.
- Este mecanismo de transferencia de energía dependiente del pH es prometedor para el diseño de sensores de oxígeno luminiscentes.
- El estudio destaca la utilidad de explotar los equilibrios de estado excitado para aplicaciones de detección.
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