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Surface Properties of Synthesized Nanoporous Carbon and Silica Matrices
Published on: March 27, 2019
Evolución de los parámetros de embalaje en los cambios estructurales de los cristales mesoporosos de sílice: tipo
Lu Han1, Keiichi Miyasaka, Osamu Terasaki
1School of Chemistry and Chemical Technology, State Key Laboratory of Composite Materials, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China.
Journal of the American Chemical Society
|June 24, 2011
Resumen
Los investigadores sintetizaron varias estructuras cristalinas mesoporosas de sílice utilizando ácido N-stearoil-l-glutámico y surfactantes Brij-56. La formación de la mesoestructura estaba controlada por las proporciones de agentes tensioactivos, influyendo en la curvatura de la interfaz y dando como resultado diversos materiales ordenados.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
- Química supramolecular de las moléculas.
Sus antecedentes:
- Los cristales mesoporosos de sílice (SMC) exhiben diversas estructuras con aplicaciones en catálisis, separación y administración de fármacos.
- El control de la morfología y dimensionalidad de las SMC es crucial para adaptar sus propiedades.
- La plantilla de agentes tensioactivos es un método clave para sintetizar materiales mesoporosos ordenados.
Objetivo del estudio:
- Para investigar la síntesis de varias estructuras cristalinas mesoporosas de sílice.
- Para entender cómo las proporciones de agentes tensioactivos influyen en la formación de la mesostructura.
- Explorar la relación entre la curvatura de la interfaz y la morfología del material resultante.
Principales métodos:
- Utilizado ácido aniónico N-stearoyl-l-glutámico (C(18) GluA) y no iónico C(16) (((EO) ((10) (Brij-56) surfactantes como co-plantillas.
- Varió la proporción de Brij-56 a C(18) GluA para controlar la curvatura de la interfaz orgánica/inorgánica.
- Empleó cristalografía de electrones y cálculos de curvatura para determinar el parámetro de embalaje local (g).
Principales resultados:
- Ha sintetizado con éxito estructuras tipo jaula, 1D lamelares (L), 2D hexagonales (C) y bicontinuas de diamante (D) y tiroides (G).
- Estableció un diagrama de campo de síntesis que muestra una secuencia de evolución de la estructura con aumento de Brij-56.
- Demostró que las micelas mixtas formadas por los tensioactivos, con su parámetro de empaque (g), dictan la mesostructura.
Conclusiones:
- La proporción de tensioactivo no iónico a aniónico es un factor crítico en el control de la mesostructura de SMC.
- La curvatura de la interfaz, modulada por el embalaje de surfactante, rige la formación de diversos motivos estructurales.
- Este estudio proporciona un marco para el diseño de arquitecturas específicas de cristales mesoporosos de sílice a través de plantillas controladas.
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