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Hálidos híbridos de perovskita de doble capa de metales de transición
Pratap Vishnoi1,2, Julia L Zuo1, Xiaotong Li3
1Materials Department and Materials Research Laboratory, University of California, Santa Barbara, California 93106, United States.
Journal of the American Chemical Society
|April 4, 2022
Resumen
Este estudio introduce nuevos haluros híbridos de perovskita en capas dobles (HLDP) con espacios de banda óptica ajustables. Los nuevos materiales amplían el alcance de los HLDP más allá de los elementos principales del grupo para aplicaciones avanzadas.
Área de la Ciencia:
- Ciencias de los materiales
- Química del estado sólido
- Química inorgánica
Sus antecedentes:
- Los haluros de perovskita doble en capas híbridas (HLDP) presentan cationes metálicos hexacoordinados dentro de las capas de perovskita y cationes orgánicos como espaciadores.
- Las investigaciones anteriores de HLDP se centraron en los iones isoelectrónicos del grupo principal 3+ con Pb (II), lo que limita la diversidad de materiales.
- La familia A2 MI MIII X8 representa una nueva clase de HLDP.
Objetivo del estudio:
- Sintetizar y caracterizar haluros HLDP nuevos más allá de los elementos tradicionales del grupo principal.
- Investigar la sintonizabilidad de las brechas de banda óptica en estos nuevos materiales.
- Para explorar las propiedades magnéticas de haluros de HLDP seleccionados.
Principales métodos:
- Síntesis de ocho nuevos haluros de HLDP de la familia A2 MI MIII X8.
- Caracterización de las brechas de banda óptica (1,55 2,05 eV) a través de la espectroscopia.
- Mediciones de la susceptibilidad magnética de compuestos específicos que contienen Ru (III) y Mo (III).
Principales resultados:
- Se han sintetizado con éxito ocho nuevos haluros de HLDP utilizando varios espaciadores orgánicos (PPDA, 1,4-BDA, 1,3-PDA) y iones metálicos (Cu, Ag, Ru, Mo).
- Se ha demostrado que las brechas de banda óptica sintonizables oscilan entre 1,55 y 2,05 eV, dependiendo de la composición de la capa, pero en gran medida independientes del espaciador orgánico.
- Los estudios magnéticos no revelaron transiciones de orden magnético; Mo(III) exhibió un comportamiento de Curie-Weiss, mientras que Ru(III) mostró desviaciones de la teoría de Kotani.
Conclusiones:
- Los haluros HLDP reportados amplían el paisaje de composición de estos materiales, incorporando metales de transición como Ru y Mo.
- Las propiedades ópticas ajustables hacen que estos nuevos HLDP sean prometedores para aplicaciones optoelectrónicas.
- Los distintos comportamientos magnéticos de Mo{III} y Ru{III} en estas estructuras merecen una mayor investigación.
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