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Transporte bidimensional de fonones en el grafeno soportado
Jae Hun Seol1, Insun Jo, Arden L Moore
1Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Science (New York, N.Y.)
|April 10, 2010
Resumen
El grafeno es el grafeno.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Física de la materia condensada Física de la materia condensada
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- El grafeno exhibe una conductividad térmica excepcionalmente alta (kappa), superando al diamante y al grafito.
- Esta propiedad sugiere aplicaciones potenciales en la gestión térmica para la nanoelectrónica.
- Sin embargo, las interacciones con el sustrato pueden alterar significativamente las propiedades de transporte térmico del grafeno.
Objetivo del estudio:
- Para determinar experimentalmente la conductividad térmica del grafeno monocapa sobre un sustrato de dióxido de silicio.
- Para comparar el rendimiento térmico del grafeno soportado por el sustrato con el grafeno suspendido y otros materiales.
- Investigar los mecanismos responsables de cualquier reducción observada en la conductividad térmica.
Principales métodos:
- Medición experimental de la conductividad térmica utilizando técnicas adecuadas para materiales a nanoescala.
- Exfoliación del grafeno monocapa sobre un soporte de dióxido de silicio.
- Análisis del comportamiento de los fonones y efectos de interfaz.
Principales resultados:
- El grafeno monocapa sobre el dióxido de silicio exhibe una conductividad térmica de aproximadamente 600 W/m·K cerca de la temperatura ambiente.
- Este valor sigue siendo más alto que el de metales como el cobre.
- La conductividad térmica medida es menor que la del grafeno en suspensión.
Conclusiones:
- La alta conductividad térmica del grafeno se conserva parcialmente incluso cuando está soportado por un sustrato como el dióxido de silicio.
- La fuga de fonones y la dispersión de la interfaz en la interfaz de soporte de grafeno reducen el transporte térmico.
- El grafeno sigue siendo un material prometedor para aplicaciones de disipación de calor, incluso en configuraciones unidas al sustrato.
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