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Perovskita híbrida quiral 2D orgánica inorgánica con dicroísmo circular sintonizable en un amplio rango de longitud
Jihoon Ahn1, Sunihl Ma1, Ji-Young Kim2
1Department of Materials Science and Engineering, Yonsei University, Seoul 03722, Republic of Korea.
Journal of the American Chemical Society
|February 13, 2020
Resumen
Los cambios en la composición química de las perovskitas híbridas inorgánicas orgánicas quirales (OIHP quirales) sintonizan las señales de dicroísmo circular (CD) y pueden activar o desactivar la actividad CD. Esto permite la ingeniería de materiales quirópticos avanzados para la optoelectrónica.
Área de la Ciencia:
- Ciencias de los materiales
- Química del estado sólido
- Optoelectrónica y sus derivados
Sus antecedentes:
- Las perovskitas orgánicas inorgánicas híbridas quirales (OIHP quirales) exhiben propiedades quirópticas únicas.
- Comprender la influencia de la composición química en estas propiedades es crucial para el diseño de materiales.
Objetivo del estudio:
- Investigar cómo la modificación de la composición química afecta las propiedades quirópticas del OIHP quiral.
- Explorar métodos para ajustar y controlar las señales de dicroísmo circular (CD) en estos materiales.
Principales métodos:
- Modificación de la relación de mezcla de aniones de bromuro y yoduro en el OIHP quiral.
- Alteración del catión espaciador orgánico (por ejemplo, utilizando grupos más grandes como C12).
- Analizando los cambios en la brecha de banda, la estructura cristalina y los espectros de CD.
Principales resultados:
- Las diferentes proporciones de haluro desplazaron la señal CD de 495 a 474 nm modificando la brecha de banda.
- Una transición de la estructura cristalina de las fases determinantes de yodo a las determinantes de bromo desactivó la señal CD.
- El uso de grupos de espaciadores orgánicos más grandes desplazó la señal CD a aproximadamente 375 nm.
Conclusiones:
- La modificación de la composición química ofrece dos formas clave de controlar las propiedades quirópticas: sintonizar la longitud de onda del CD a través de la estructura de la banda y encender / apagar el CD a través de cambios estructurales.
- Estos hallazgos son valiosos para la ingeniería estructural de materiales quirópticos de alto rendimiento.
- Las aplicaciones potenciales incluyen dispositivos de emisión de luz con espín polarizado y optoelectrónica basada en la polarización.
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