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El polimorfismo de Zn[Au(CN) 2) 2 y su respuesta sensorial luminiscente al vapor de NH 3
Michael J Katz1, Taramatee Ramnial, Hua-Zhong Yu
1Department of Chemistry, Simon Fraser University, 8888 University Drive, Burnaby, British Columbia, Canada V5A 1S6.
Journal of the American Chemical Society
|July 23, 2008
Resumen
Los investigadores sintetizaron cuatro formas de Zn[Au(CN) 2 2 2 , revelando redes interpenetradas con enlaces oro-oro. Tres formas exhiben luminiscencia, sensibles al vapor de amoníaco, lo que permite la detección de gases de bajo nivel.
Área de la Ciencia:
- Ciencia de los materiales Ciencia de los materiales.
- La cristalografía es una técnica de cristalografía.
- Coordinación Química de la Coordinación
Sus antecedentes:
- El polimorfismo en las estructuras metal-orgánicas (MOF) influye en las propiedades del material.
- El complejo Zn[Au(CN) 2) 2 ofrece potencial para aplicaciones funcionales debido a su estructura única.
Objetivo del estudio:
- Para sintetizar y caracterizar diversas formas polimórficas de Zn[Au(CN) 2) 2.2.
- Investigar las propiedades estructurales, espectroscópicas y de detección de estos polimorfos.
Principales métodos:
- Difracción de rayos X monocristalino para la determinación estructural.
- Técnicas espectroscópicas (por ejemplo, luminiscencia) para el análisis de propiedades.
- Estudios de adsorción/desorción de gases para las capacidades de detección.
Principales resultados:
- Se sintetizaron cuatro polimorfos distintos de Zn[Au(CN) 2 2 2 , con centros de zinc tetraédricos y redes 3D interpenetradas.
- La luminiscencia se observó en tres polimorfos, correlacionados con las distancias de enlace oro-oro (3.113.33 Å).
- El vapor de amoníaco indujo cambios estructurales y cambios de luminiscencia, lo que permite la detección hasta 1 ppb.
Conclusiones:
- El estudio aclara la diversidad estructural y la luminiscencia sintonizable de los polimorfos Zn[Au[CN]2]2.
- Estos materiales demuestran potencial como sensores sensibles de gas de amoníaco.
- Los hallazgos contribuyen a la comprensión de las relaciones estructura-propiedad en polímeros de coordinación.
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