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El transporte de carga en uniones de una sola molécula de tipo dimetildihidropireno con conmutación por fotosíntesis
Diego Roldan1, Veerabhadrarao Kaliginedi, Saioa Cobo
1Département de Chimie Moléculaire, UMR CNRS-5250, Institut de Chimie Moléculaire de Grenoble, FR CNRS-2607, Université Joseph Fourier Grenoble I, BP 53, 38041 Grenoble Cedex 9, France.
Journal of the American Chemical Society
|April 12, 2013
Resumen
Los investigadores estudiaron las moléculas fotoswitchable para la electrónica. Un derivado de dimetildihidropireno (DHP) mostró grandes cambios reversibles en la conductividad eléctrica, logrando una alta relación encendido/apagado para aplicaciones de conmutación molecular.
Área de la Ciencia:
- La electrónica molecular es la electrónica molecular.
- Química supramolecular de las moléculas.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las moléculas fotointercambiables ofrecen propiedades electrónicas sintonizables.
- Las uniones de una sola molécula son cruciales para los dispositivos electrónicos a nanoescala.
Objetivo del estudio:
- Investigar las propiedades de conducción de un derivado de dimetildihidropireno (DHP) con conmutación fotográfica.
- Correlacionar los cambios en la estructura molecular con las variaciones de conductividad en las uniones de una sola molécula.
Principales métodos:
- Utilizó la técnica de unión de ruptura controlada mecánicamente (MCBJ).
- Las uniones de una sola molécula fabricadas y medidas con un derivado de DHP.
Principales resultados:
- Se ha demostrado la conmutación de conductividad reversible en moléculas individuales de DHP.
- Se observó una gran caída en la conductividad (> 10 ^ 4 relación ON / OFF) después de la isomerización de DHP.
- Se confirmó una excelente reversibilidad de la conmutación de la conductividad.
Conclusiones:
- Los derivados de DHP fotointercambiables son prometedores para aplicaciones electrónicas moleculares.
- Los cambios estructurales inducidos por la isomerización modulan efectivamente la conductancia de una sola molécula.
- Las altas relaciones encendido/apagado y la reversibilidad son claves para los interruptores moleculares prácticos.
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