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Formación de monocapas autoensambladas altamente ordenadas de alquinas en el sustrato Au(111)
Tomasz Zaba1, Agnieszka Noworolska, Carleen Morris Bowers
1Smoluchowski Institute of Physics, Jagiellonian University , ul. Reymonta 4, 30-059 Krakow, Poland.
Journal of the American Chemical Society
|August 8, 2014
Resumen
Las monocapas autoensambladas (SAM) de alto orden se formaron a partir de n-alquinas terminales en superficies de oro. Estos SAMs alquinos exhiben propiedades similares a los SAMs alcanetiolados, que requieren condiciones libres de oxígeno para una alta calidad.
Área de la Ciencia:
- Ciencias de la superficie Ciencias de la superficie.
- Química de los materiales química de los materiales.
- Nanotecnología La nanotecnología es la nanotecnología.
Sus antecedentes:
- Las monocapas autoensambladas (SAM) son cruciales para modificar las propiedades de las superficies.
- Los alcanetiolatos en el oro están bien estudiados, lo que proporciona un punto de referencia para la comparación.
- Comprender los precursores alternativos para los SAM es importante para el desarrollo de materiales.
Objetivo del estudio:
- Investigar la formación y las propiedades de SAMs derivados de n-alquinas terminales en Au111).
- Comparar las características estructurales y físicas de los SAMs basados en alquinos con las de los SAMs alcanetiolados tradicionales.
- Identificar los factores críticos que influyen en la calidad y el orden de los SAMs alquinos.
Principales métodos:
- Preparación de SAMs utilizando las n-alquinas terminales (C5-C11) en Au{111) a 60 °C.
- Caracterización a través de microscopía de túnel de barrido (STM) para la morfología de la superficie.
- Análisis utilizando espectroscopia de absorción de reflexión infrarroja (IRRAS) y espectroscopia de fotoelectrones de rayos X (XPS) para obtener información química y estructural.
- Mediciones del ángulo de contacto para evaluar la hidrofobia de la superficie.
Principales resultados:
- Se confirmó la formación de SAMs altamente ordenados a partir de n-alquinas en Au{111}.
- Se encontró que las densidades de embalaje y las orientaciones moleculares eran similares a las de los SAMs de alcanetiolato.
- El alto orden de la superficie, la hidrofobidad y la densidad de embalaje indican fuertes similitudes con los SAM alcanetiolados.
- La contaminación de oxígeno conduce a contaminantes oxidados y películas desordenadas debido a la oxidación del grupo alquino.
Conclusiones:
- Las n-alquinas terminales pueden formar SAMs ordenados de alta calidad en Au{111) con propiedades comparables a las de los alcanetiolatos.
- El proceso de formación es sensible al oxígeno, lo que causa una oxidación indeseable de la porción de alquino.
- Estos hallazgos amplían el alcance de los precursores para crear SAMs bien ordenados en superficies de oro.
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