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La movilidad del radical fullereno de larga vida en estado sólido y la dependencia no lineal de la temperatura

Yoko Abe¹, Hideyuki Tanaka, Yunlong Guo

¹Department of Chemistry, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 112-0033, Japan.

Journal of the American Chemical Society

|February 19, 2014

Resumen

Un dímero de fullereno se disocia en radicales al calentarse, aumentando significativamente la movilidad de los electrones. Este proceso reversible en cristales de plástico mejora la conductividad diez veces.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
Química del estado sólido.
Química Física es la química física.

Sus antecedentes:

Los dimeros de fullereno ([C60R]2) son moléculas compuestas de dos unidades de fullereno unidas por un único enlace.
Comprender el comportamiento térmico y las propiedades electrónicas de los derivados del fullereno es crucial para el desarrollo de nuevos materiales electrónicos.

Objetivo del estudio:

Para investigar la disociación térmica de un dímero de fullereno de enlace único en estado sólido.
Para analizar el impacto de la generación de radicales en la movilidad de electrones del sólido fullereno.
Para aclarar la relación entre la estructura cristalina y las propiedades de transporte de carga.

Principales métodos:

Síntesis de un dimero de fullereno de enlace único ([C60R]2).
Análisis térmico del dímero de fullereno en estado sólido.
Medidas dependientes de la temperatura de la movilidad de los electrones en el sólido.
Análisis de la disociación del par de radicales y las interacciones de los radicales libres.

Principales resultados:

El dimero de fullereno ([C60R]2) se disocia térmicamente en un par de radicales de fullereno (C60R(•)) al calentarse.
La movilidad de los electrones aumenta por un factor de 10, alcanzando 1,5 × 10{-3} cm{-2} V{-1} s{-1}), debido a la disociación radical.
Se observa una sorprendente no linealidad en la dependencia de la temperatura de la movilidad de los electrones, vinculada a la naturaleza cristalina plástica del fullereno.

Conclusiones:

La disociación térmica de dímeros de fullereno en radicales es un mecanismo viable para mejorar la movilidad de electrones en materiales en estado sólido.
La naturaleza cristalina plástica de los cristales de fullereno juega un papel clave en el observado transporte de carga no lineal.
Este estudio pone de relieve el potencial de los sistemas radicales de fullereno para aplicaciones electrónicas avanzadas.

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