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Fotocromismo "encendido" / "apagado" impulsado por la luz visible de un complejo de coordinación de diarileto de
Jingjing Xu1, Henrieta Volfova2, Roger J Mulder3
1School of Chemistry , The University of Melbourne , Melbourne , Victoria 3010 , Australia.
Journal of the American Chemical Society
|July 13, 2018
Resumen
Desarrollamos el primer complejo de diarilethene basado en polioxometalato fotocrómico. Esta nueva estructura de mancuernas moleculares exhibe un cambio reversible entre dos estados utilizando luz visible, allanando el camino para nuevos materiales fotorresponsivos.
Área de la Ciencia:
- Química supramolecular
- Ciencias de los materiales
- La fotoquímica
Sus antecedentes:
- Los polioxometalatos (POM) son grupos inorgánicos versátiles con propiedades electrónicas sintonizables.
- Los diariletenos (DAE) son moléculas fotocrómicas conocidas por sus cambios de color reversibles tras la irradiación de luz.
- La combinación de POM y DAE ofrece una vía para crear materiales fotorresponsivos avanzados.
Objetivo del estudio:
- Para sintetizar y caracterizar el primer complejo de coordinación de diarylethene basado en polioxometalato.
- Investigar el autoensamblaje, la estructura y las propiedades fotocrómicas del nuevo complejo.
- Evaluar el comportamiento de conmutación y las características fotofísicas del conjunto POM-DAE.
Principales métodos:
- Coordinación química para la síntesis compleja.
- Espectroscopia de resonancia magnética nuclear (RMN) (1H, 19F) para el análisis estructural y de composición.
- Espectrometría de masas (ESI-QTOF-MS) para la determinación del peso molecular.
- Espectroscopia UV visible (UV-vis) y dispersión de rayos X de ángulo pequeño (SAXS) para estudios estructurales y fotofísicos.
- Configuración personalizada para la determinación del rendimiento cuántico y la prueba de resistencia a la fatiga.
Principales resultados:
- Síntesis exitosa de un nuevo complejo de coordinación de diarileto basado en polioxometalato.
- El complejo se autoorganiza en una estructura de mancuernas moleculares impulsada por factores electrostáticos y estéricos.
- La unidad diarylethene dentro del complejo exhibe un cambio inducido por la luz entre dos estados.
- Se obtuvieron datos fotofísicos detallados, incluidas las eficiencias cuánticas y la resistencia a la fatiga.
Conclusiones:
- El primer complejo de coordinación fotocrómico POM-DAE fue sintetizado y caracterizado con éxito.
- La arquitectura de las mancuernas moleculares es crucial para el comportamiento fotocrómico observado.
- El complejo demuestra una conmutación fotocrómica eficiente y reversible, destacando su potencial en electrónica molecular y dispositivos ópticos.
- Este trabajo amplía el alcance de los materiales funcionales basados en POM con capacidades fotorresponsivas.
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