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Cristales coloidales fototérmicamente reconfigurables en una interfaz de fluido, un enfoque genérico para propiedades
Jacopo Vialetto1, Sergii Rudiuk1, Mathieu Morel1
1PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.
Journal of the American Chemical Society
|July 26, 2021
Resumen
Los investigadores desarrollaron un nuevo método para controlar ópticamente los cristales coloidales en las interfaces de fluidos. Esta técnica permite propiedades de celosía sintonizables y formación de patrones dinámicos utilizando estímulos de luz.
Área de la Ciencia:
- Ciencias de los materiales
- Física de la materia blanda
- Ciencia de los coloides
Sus antecedentes:
- El conjunto coloidal ópticamente direccionable es crucial para los materiales 2D reconfigurables.
- Lograr esto en las interfaces de fluidos generalmente requiere ingeniería de interfaces especializada.
Objetivo del estudio:
- Presentar un método genérico para los cristales coloidales ópticamente reconfigurables en la interfaz aire/agua.
- Introducir un nuevo mecanismo para convertir la luz en propiedades de red sintonizables.
Principales métodos:
- Utilizando partículas aniónicas que absorben la luz en la interfaz aire/agua con surfactante catiónico.
- Utilizando irradiación de baja y alta intensidad para controlar el espaciamiento entre las partículas e inducir la fusión/recristalización.
- Investigando la tensión termocapillar y la difusividad de las partículas como mecanismos para la fusión fotorreversible.
Principales resultados:
- Demostró un control sin precedentes sobre el espaciamiento entre las partículas mientras conservaba los estados cristalinos.
- Se han logrado ciclos de fusión y recristalización controlables mediante estímulos sucesivos de encendido/apagado de la luz.
- Patrones dinámicos observados como cristales auto-curativos y ensamblaje multirresponsivo con estímulos luminosos y magnéticos.
Conclusiones:
- El método desarrollado ofrece una plataforma versátil para crear materiales 2D reconfigurables.
- El mecanismo de la tensión termocapillar y la difusividad de partículas proporciona una nueva comprensión del ensamblaje coloidal inducido por la luz.
- Este enfoque permite la formación de patrones dinámicos y el control de múltiples respuestas de los sistemas coloidales.
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