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Impacto de los ligandos en las propiedades estructurales y ópticas de los nanocúmulos de Ag29
Yuan Zeng1, Shana Havenridge2, Mustafa Gharib1,3
1Department of Physics and Center for Hybrid Nanostructure (CHyN), University of Hamburg, Luruper Chaussee 149, Hamburg 22761, Hamburg, Germany.
Journal of the American Chemical Society
|June 17, 2021
Resumen
La optimización de ligandos mejoró significativamente el rendimiento cuántico de los nanocúmulos de plata (NC). Mientras que el núcleo metálico dicta la fotoluminiscencia, los ligandos son cruciales para ajustar el rendimiento cuántico final.
Área de la Ciencia:
- Ciencia de los nanomateriales
- Química Física
- Química computacional
Sus antecedentes:
- Los nanocúmulos de plata atómicamente precisos (NC) exhiben propiedades ópticas únicas.
- La comprensión de la influencia de los ligandos de superficie en la estructura NC y la fotoluminiscencia es crítica.
Objetivo del estudio:
- Investigar el papel del intercambio de ligandos en la modificación de las propiedades estructurales y ópticas de los nanocúmulos de plata de 29 átomos.
- Para lograr un rendimiento cuántico mejorado (QY) a través de la optimización del ligando.
Principales métodos:
- Estrategia y optimización del intercambio de ligandos.
- Espectrometría de masas de alta resolución para el seguimiento del intercambio de ligandos.
- Teoría funcional de la densidad (DFT) para el análisis estructural.
- Espectrometría de masas de movilidad iónica (IM MS) para la verificación experimental de la estructura mediante el análisis de la sección transversal de colisión (CCS).
Principales resultados:
- Se logró una mejora de ~44 veces en la QY para Ag29 (BDT) 12 - x (DHLA) x NC a través de la optimización de ligandos.
- DFT y IM MS confirmaron una estructura probable para Ag29 ((DHLA) 12 NC, con un núcleo icosaédrico y una cáscara Ag16S24.
- El análisis de varias composiciones NC (Ag29-yAuy(BDT)12-x(DHLA)x) reveló el papel del núcleo metálico en el inicio de la fotoluminiscencia (PL) y el papel de los ligandos en la determinación de PLQY.
Conclusiones:
- La ingeniería de ligandos es una herramienta poderosa para mejorar el rendimiento cuántico de fotoluminiscencia de los nanocúmulos de plata.
- La interacción entre el núcleo metálico y los ligandos de la superficie dicta el comportamiento fotofísico de los nanocúmulos atómicamente precisos.
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