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Control de coordinación-química de la conductividad de protones en el icónico material marco metal-orgánico HKUST-1
Nak Cheon Jeong1, Bappaditya Samanta, Chang Yeon Lee
1Department of Chemistry and International Institute for Nanotechnology, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|December 14, 2011
Resumen
Las estructuras metal-orgánicas (MOF) como HKUST-1 exhiben una conductividad protónica significativa. Esta conductividad se puede ajustar de manera reversible cambiando las moléculas coordinadas y de llenado de poros, ofreciendo nuevas posibilidades para los materiales conductores.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Química Química es la química.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las estructuras metálicas orgánicas (MOF) son materiales porosos con estructuras sintonizables.
- HKUST-1 es un MOF conocido por sus sitios metálicos accesibles.
Objetivo del estudio:
- Para investigar la conductividad iónica en MOFs.
- Para explorar la conductividad de protones en HKUST-1.
- Comprender los factores que influyen en la conductividad de los protones en los MOF.
Principales métodos:
- Sorción de varias moléculas (metanol, acetonitrilo, hexano) en HKUST-1.
- Medición de la conductividad de corriente alterna.
- Modulación de moléculas coordinadas y de llenado de poros.
Principales resultados:
- Inesperadamente se observó una sustancial conductividad de protones en HKUST-1 después de la sorción de metanol.
- La conductividad de los protones aumentó ~75 veces cuando el acetonitrilo coordinado fue reemplazado por agua.
- La conductividad de los protones se volvió insignificante cuando el metanol fue reemplazado por el hexano.
Conclusiones:
- HKUST-1 exhibe una conductividad de protones ajustable.
- Los sitios de Cu (II) en HKUST-1 pueden hacer que el agua coordinada sea lo suficientemente ácida para facilitar la transferencia de protones.
- La identidad química tanto de las moléculas coordinadas por los nodos como de las que llenan los poros se puede variar de forma independiente para modular la conductividad de los protones.
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