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Una ruta de síntesis simple para las barras de sílice SBA-15 monodispersas

Abdelhamid Sayari¹, Bao-Hang Han, Yong Yang

¹Centre for Catalysis Research and Innovation (CCRI), Department of Chemistry, University of Ottawa, Ottawa, Ontario, Canada K1N 6N5. abdel.sayari@science.uottawa.ca

Journal of the American Chemical Society

|November 4, 2004

Resumen

Un nuevo método sintetiza varillas SBA-15 uniformes con alto rendimiento sin sales inorgánicas. Las condiciones estáticas y las temperaturas controladas son clave para la síntesis reproducible de estos materiales de sílice mesoporosa.

Área de la Ciencia:

Ciencia de los materiales Ciencia de los materiales.
Nanotecnología La nanotecnología es la nanotecnología.
Síntesis Química La síntesis química es el proceso de síntesis química.

Sus antecedentes:

SBA-15 es un material de sílice mesoporoso con una estructura hexagonal.
El control de la morfología y el tamaño de los poros de SBA-15 es crucial para sus aplicaciones.
Los métodos de síntesis existentes pueden ser complejos y pueden requerir sales inorgánicas.

Objetivo del estudio:

Desarrollar una síntesis simple, flexible y reproducible de varillas rectas SBA-15 de facetas hexagonales.
Para lograr altos rendimientos (aprox. 100%) y tamaños de partículas uniformes.
Para investigar el efecto de las condiciones de síntesis en el tamaño de los poros.

Principales métodos:

Condiciones de síntesis estáticas (sin agitación).
Etapas de temperatura controlada, con la primera etapa no excediendo los 60°C.
Síntesis sin el uso de sales inorgánicas.

Principales resultados:

Se han sintetizado con éxito barras rectas SBA-15 de facetas hexagonales con tamaños uniformes (aprox. 1,5 x 0,4 μm). es decir, su tamaño es de 1,5 x 0,4 μm.
Alcanzó altos rendimientos (aprox. 100%) bajo condiciones estáticas.
Se obtuvieron tamaños de poro dependientes de la temperatura que van desde 5,8 a 12,5 nm, mientras que las dimensiones externas se mantuvieron similares.

Conclusiones:

La ausencia de agitación es esencial para la preparación de barras SBA-15 cortas y monodispersas.
Controlar la temperatura de reacción inicial por debajo de 60°C es crítico.
No se requieren sales inorgánicas para esta síntesis, lo que simplifica el proceso.

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