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El mosaico de la carga superficial en la electrificación de contacto
H T Baytekin1, A Z Patashinski, M Branicki
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA.
Science (New York, N.Y.)
|June 25, 2011
Resumen
La carga de contacto de los dieléctricos crea un mosaico a nanoescala de cargas opuestas en cada superficie, desafiando la suposición de larga data de la distribución uniforme de la carga. Este hallazgo revela un mecanismo más complejo para la generación de electricidad estática.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La electricidad tribal.
- Física de la superficie Física de las superficies
Sus antecedentes:
- La generación de electricidad estática a través del contacto dieléctrico es un fenómeno bien conocido.
- La comprensión convencional asume una distribución uniforme de la carga a través de las superficies después del contacto y la separación.
- Este modelo de carga uniforme se basa en propiedades de materiales homogéneos.
Objetivo del estudio:
- Para investigar la distribución real de la carga en las superficies dieléctricas después de la electrificación de contacto.
- Desafiar el modelo prevaleciente de transferencia uniforme de carga en la triboelectricidad.
- Para caracterizar las características a nanoescala de la carga superficial.
Principales métodos:
- Utilizando técnicas avanzadas de sondeo de superficie para analizar la distribución de la carga a nanoescala.
- Examinar varios materiales dieléctricos para identificar las características comunes de carga.
- Cuantificar la densidad de carga soportada por las estructuras superficiales observadas.
Principales resultados:
- Demostró que la electrificación por contacto da como resultado un mosaico aleatorio de regiones cargadas de manera opuesta en cada superficie dieléctrica.
- Se observó que estos mosaicos de carga a nanoescala son topológicamente consistentes a través de diferentes materiales dieléctricos.
- Se encontró que estos mosaicos de carga superficial pueden acomodar densidades de carga significativamente más altas de lo estimado previamente.
Conclusiones:
- El modelo tradicional de carga uniforme por contacto es incorrecto.
- Las superficies dieléctricas exhiben distribuciones de carga heterogéneas a nanoescala después de la electrificación.
- Esta comprensión revisada de los mosaicos de carga tiene implicaciones para campos que dependen de fenómenos de electricidad estática.
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