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Akshaya Chemmangat1, Jishnudas Chakkamalayath1, Jeffrey T DuBose1
1Radiation Laboratory, Department of Chemistry and Biochemistry, and Department of Chemical and Biomolecular Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States.
Journal of the American Chemical Society
|January 24, 2024
Resumen
Descubrimos que la modificación de tintes de rodamina unidos a los nanocristales de perovskita halogenada de plomo controla la transferencia de energía. La unión más fuerte de rose Bengal a las perovskitas CsPbI3 maximizó la eficiencia de transferencia de energía triple.
Área de la Ciencia:
- Ciencias de los materiales
- La fotoquímica
- Nanotecnología
Sus antecedentes:
- Los nanocristales de perovskita halogenada de plomo (LHP) exhiben una amplia absorción de luz, lo que los hace prometedores para la fotocatálisis y la optoelectrónica.
- La transferencia de energía entre los LHP y los tintes aceptores puede ajustar las propiedades del material híbrido y extender la vida útil del estado excitado.
- La comprensión de los factores que rigen la transferencia de energía es crucial para el diseño de sistemas híbridos de semiconductores y tintes avanzados.
Objetivo del estudio:
- Investigar los factores clave que influyen en la transferencia de energía de tripletes entre los nanocristales de perovskita CsPbI3 y los tintes de rodamina sujetos a la superficie.
- Para correlacionar la estructura del tinte, la unión superficial y la cinética y eficiencia de la transferencia de energía.
- Explorar la ingeniería de brechas de banda en perovskitas halogenadas mixtas para la generación controlada de estados singlet/triplet.
Principales métodos:
- Utilizó espectroscopias de absorción y emisión para estudiar los mecanismos de transferencia de energía.
- Se han investigado tres tintes de rodamina (rodamina B, isotiocianato de rodamina B, rosa de Bengala) con diferentes grupos colgantes.
- Se utilizan perovskitas mixtas de haluros CsPb ((Br1-xIx) 3 para ajustar la energía de la brecha de banda.
Principales resultados:
- La unión más fuerte de rose Bengal a CsPbI3 dio como resultado la mayor eficiencia de transferencia de energía triple (96%) con una constante de velocidad de 1 × 10 ^ 9 s ^ 1.
- La transferencia de energía triplet en CsPbI3-rose Bengal fue ~ 100 veces más lenta que la transferencia de energía singlet en CsPbBr3-rose Bengal (1.1 × 10 ^ 11 s ^ 1).
- Las perovskitas mixtas de halogenuros permitieron un ajuste sistemático de la generación del estado excitado de singlet vs. triplet (0-100%) ajustando la relación Br/I.
Conclusiones:
- Los grupos colgantes en los tintes aceptores tienen un impacto significativo en la unión superficial y la cinética y la eficiencia de la transferencia de energía subsiguientes.
- La ingeniería de bandgap de las perovskitas halogenadas ofrece una ruta para controlar la población de estados excitados singlet y triplet en sistemas híbridos.
- Estos hallazgos permiten una modulación precisa de la transferencia de energía en híbridos de semiconductores y tintes para aplicaciones optoelectrónicas avanzadas.
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