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Facile Synthesis of Colloidal Lead Halide Perovskite Nanoplatelets via Ligand-Assisted Reprecipitation
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Descifrando la competencia de halógenos en el crecimiento de perovskita halogenada orgánica
Bin Yang, Jong Keum, Olga S Ovchinnikova
1Key Laboratory of Polar Materials and Devices (MOE), East China Normal University , Shanghai 200241, China.
Journal of the American Chemical Society
|March 3, 2016
Resumen
Se aclara la competencia de haluros durante la síntesis de perovskita. Los iones de cloro no se incorporan a la red cristalina, sino que residen en los límites de los granos, guiando la futura ingeniería de dispositivos optoelectrónicos.
Área de la Ciencia:
- Ciencias de los materiales
- Química del estado sólido
- Optoelectrónica y sus derivados
Sus antecedentes:
- Las perovskitas organometálicas (OHP) son prometedoras para los dispositivos optoelectrónicos de bajo costo.
- La comprensión de la competencia de iones halogenados durante la síntesis de OHP es crucial para la calidad de la película.
Objetivo del estudio:
- Investigar el papel y la ubicación de los diferentes iones haluro (I-, Br-, Cl-) durante la cristalización de la OHP.
- Aclarar el comportamiento de incorporación de Cl- en películas de perovskita mixta.
Principales métodos:
- Difracción de rayos X in situ para estudiar la dinámica de la cristalización.
- Espectrometría de masa de iones secundarios de tiempo de vuelo (TOF-SIMS) ex situ para análisis químicos.
Principales resultados:
- Tanto Br- como Cl- pueden promover el crecimiento de cristales de OHP.
- El I- reactivo impide la incorporación de Br- o Cl- en la red de perovskita.
- Los clones se encuentran localizados en los límites de grano de las películas de perovskita.
Conclusiones:
- Este estudio aclara las distintas funciones de los iones haluro en la formación de OHP.
- Los resultados proporcionan orientación para la ingeniería de películas de perovskita de alta calidad para aplicaciones optoelectrónicas avanzadas.
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