Role of Inter-Particle Connectivity in the Photo-Carrier Cooling Dynamics in Perovskite Quantum Dot Solids

Intraband carrier relaxation in quantum dots (QDs) has been a subject of extensive spectroscopic investigation for several decades, and have been used to optimize the efficiency of opto-electronic processes. In the past few years, metal halide perovskites-based QDs have been shown to exhibit slow ho...

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Detalles Bibliográficos
Autores: Tiede, David O., Koch, Katherine A., Romero-Pérez, Carlos, Ucer, K. Burak, Calvo, Mauricio E., Galisteo-López, Juan F., Míguez, Hernán, Srimath Kandada, Ajay Ram
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2024
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/374211
Acceso en línea:http://hdl.handle.net/10261/374211
https://api.elsevier.com/content/abstract/scopus_id/85205099663
Access Level:acceso abierto
Palabra clave:Quantum dots
Carrier cooling
Perovskites
Photo-excitation dynamics
Descripción
Sumario:Intraband carrier relaxation in quantum dots (QDs) has been a subject of extensive spectroscopic investigation for several decades, and have been used to optimize the efficiency of opto-electronic processes. In the past few years, metal halide perovskites-based QDs have been shown to exhibit slow hot-carrier cooling characteristics that are desirable for photo-energy harvesting technologies. While several mechanisms are proposed to rationalize the retardation of the cooling dynamics, including hot-phonon bottleneck and polaronic effects, the role of inter-particle connectivity in these dynamics is largely ignored. Here, an in-depth study of photo-excitation dynamics and carrier cooling on perovskite QD solids with varying degrees of inter-dot coupling is presented. It is observed that inter-particle connectivity has deterministic effects on the many-body interactions that are relevant for carrier cooling. These include carrier–carrier interactions that result in Auger-reheating of the carriers, and lattice characteristics that subsequently affect the phonon-assisted cooling dynamics. This spectroscopic study of ultrafast carrier dynamics in perovskite QD solids establishes inter-dot separation as a critical material design parameter for the optimization of photo-generated carrier temperature, which fundamentally determines the luminescence characteristics and thus the opto-electronic quality of the material.