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Modulación de la excitación de las nanopartículas de conversión ascendente para el control tipo interruptor de la
Peter Dawson1, Marek Romanowski1
1Department of Biomedical Engineering , University of Arizona , Tucson , Arizona 85721 , United States.
Journal of the American Chemical Society
|April 18, 2018
Resumen
Los investigadores demuestran un control similar a un interruptor sobre la luminiscencia ultravioleta (UV) mediante el uso de nanopartículas de conversión ascendente de fluoruro de sodio (NaYF4) optimizadas. Este método permite una modulación precisa de la intensidad UV para posibles aplicaciones teranosticas.
Área de la Ciencia:
- Ciencias de los materiales
- Nanotecnología
- La luminiscencia
Sus antecedentes:
- Las nanopartículas de conversión ascendente (UNP) ofrecen propiedades ópticas únicas para diversas aplicaciones.
- El control de la intensidad de luminiscencia, especialmente en el espectro UV, es crucial para las funcionalidades avanzadas del material.
- Los PNU a base de fluoruro de sodio dopados con iones de tierras raras son prometedores para la conversión de energía.
Objetivo del estudio:
- Para demostrar el control similar a un interruptor sobre la intensidad de la luminiscencia ultravioleta (UV) en las nanopartículas de conversión ascendente (UNP) NaYF4: Yb3+, Tm3+.
- Para investigar el efecto de la concentración de dopaje de Ytterbium en la luminiscencia UV.
- Para explorar la aplicación de la transferencia de energía UV a otras moléculas.
Principales métodos:
- Utilizó la modulación de ancho de pulso de excitación de 980 nm (PWM) en NaYF4: Yb3 +, Tm3 + UNPs.
- Concentraciones de dopaje de Ytterbium optimizadas para mejorar la luminiscencia UV.
- Se ha investigado la transferencia de energía UV de los PNU al 9,10-difenilantraceno (DPA).
Principales resultados:
- Se ha logrado un control similar a un interruptor sobre la intensidad de la luminiscencia UV mediante el uso de la excitación PWM de 980 nm.
- El dopaje optimizado de Ytterbium mejoró la luminiscencia UV en un orden de magnitud.
- Se ha demostrado un control de tres órdenes de magnitud sobre la intensidad de la luminiscencia UV con una emisión NIR mantenida a 800 nm.
- Se ha transferido con éxito la energía UV de UNP a DPA.
Conclusiones:
- La modulación del ancho de pulso de la excitación NIR proporciona un control preciso y similar a un interruptor sobre la luminiscencia UV de NaYF4: Yb3 +, Tm3 + UNPs.
- Los PNU optimizados exhiben una mayor emisión de UV y capacidades de transferencia de energía controlables.
- El control independiente de la emisión NIR y la transferencia de energía UV abre posibilidades para sistemas teranosticos multifuncionales.
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