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Gotas de agua poliédricas: transiciones de forma y mecanismo
Shir R Liber1, Orlando Marin1, Alexander V Butenko1
1Physics Department & Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 5290002, Israel.
Journal of the American Chemical Society
|April 21, 2020
Resumen
Las gotas de aceite pueden formar formas poliédricas, incluso con una interfaz cóncava. Este descubrimiento apoya un nuevo mecanismo impulsado por la elasticidad de una monocapa cristalina, no por la curvatura interfacial.
Área de la Ciencia:
- Física de la materia blanda
- Ciencias de los materiales
- Química de las superficies
Sus antecedentes:
- Las gotas de líquido clásicas suelen ser redondeadas debido a la tensión superficial.
- Estudios recientes muestran que las gotas de aceite pueden cambiar a formas poliédricas.
- Se discute el mecanismo y el papel de la curvatura interfacial en esta transición.
Objetivo del estudio:
- Para investigar el mecanismo detrás de la formación de gotas poliédricas.
- Para determinar el papel de la curvatura interfacial en las facetas de gotas.
- Para apoyar o refutar los mecanismos propuestos para las transiciones de forma de gotas.
Principales métodos:
- Observación experimental de las gotas de agua en suspensión de aceite.
- Análisis de las formas de las gotas y de las propiedades interfaciales.
- Investigación de las monocapas autoensambladas en la interfaz aceite-agua.
Principales resultados:
- Las gotas de agua en suspensión de aceite forman espontáneamente formas poliédricas.
- La facetación se produce a pesar de una interfaz cóncava aceite-agua.
- Los resultados contradicen los mecanismos que requieren una interfaz convexa.
Conclusiones:
- La elasticidad de una monocapa cristalina autoensamblada impulsa el facetado de gotas, independientemente de la curvatura de la interfaz.
- Este hallazgo apoya un mecanismo alternativo para la formación de gotas poliédricas.
- El estudio abre vías para sintetizar nanopartículas facetadas y comprender la morfogénesis.
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