Probing the Multiexcitonic Dynamics in CsPbI3 Nanocrystals across the Temperature-Induced Reversible Phase Transitions
(2023) In Advanced Energy Materials 13(30).- Abstract
CsPbI3 nanocrystals (CPI NCs) have become a trending research topic due to their impressive potential in functional optoelectronic devices and optical gain applications. Their optical responses are governed by carrier dynamics, which is greatly influenced by temperature and corresponding phase structure due to the effects of inherently electron-phonon coupling. Notably, CPI NCs have been identified to adopt an unexpectedly stable cubic phase from room temperature to liquid helium temperature. Here, using in situ cryogenic electron diffraction measurements, it is unambiguously demonstrated that CPI NCs undergo consecutive cubic-tetragonal-orthorhombic phase transitions from 298 to 100 K. The corresponding temperature-dependent... (More)
CsPbI3 nanocrystals (CPI NCs) have become a trending research topic due to their impressive potential in functional optoelectronic devices and optical gain applications. Their optical responses are governed by carrier dynamics, which is greatly influenced by temperature and corresponding phase structure due to the effects of inherently electron-phonon coupling. Notably, CPI NCs have been identified to adopt an unexpectedly stable cubic phase from room temperature to liquid helium temperature. Here, using in situ cryogenic electron diffraction measurements, it is unambiguously demonstrated that CPI NCs undergo consecutive cubic-tetragonal-orthorhombic phase transitions from 298 to 100 K. The corresponding temperature-dependent multiexcitonic dynamics are investigated in each phase by combining time-resolved photoluminescence and transient absorption spectroscopy. In addition to the temperature dependency, the lifetime of both excitons and biexcitons evidently depends on the phase structures of the CPI NCs, highlighting the crucial effect of crystal structure on the carrier dynamics. Moreover, the biexciton binding energy increases with higher crystal symmetry due to the decrease of the dielectric constant. The findings shed light on the structural phase transition and its relationship to the carrier dynamics in all-inorganic perovskite NCs, which provides critical insight into the structure-performance relationship in CPI NCs for promising applications in optoelectronic devices.
(Less)
- author
- Liu, Siyu ; Geng, Huifang ; Geng, Huaxiu ; Huang, Zhuanzhuan ; Deng, Shibin ; Shen, Xi ; Yu, Richeng ; Zheng, Kaibo LU ; Canton, Sophie E. and Fu, Xuewen
- organization
- publishing date
- 2023-08-11
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- biexcitons, cryogenic electron diffraction, CsPbI3 perovskite nanocrystals, multiexcitonic dynamics, phase transitions
- in
- Advanced Energy Materials
- volume
- 13
- issue
- 30
- article number
- 2301097
- publisher
- Wiley-Blackwell
- external identifiers
-
- scopus:85163011282
- ISSN
- 1614-6832
- DOI
- 10.1002/aenm.202301097
- language
- English
- LU publication?
- yes
- id
- 2e5a9b8f-d1e5-4902-b0a0-6baf85bafb6b
- date added to LUP
- 2023-10-09 13:46:16
- date last changed
- 2023-10-13 11:52:13
@article{2e5a9b8f-d1e5-4902-b0a0-6baf85bafb6b,
abstract = {{<p>CsPbI<sub>3</sub> nanocrystals (CPI NCs) have become a trending research topic due to their impressive potential in functional optoelectronic devices and optical gain applications. Their optical responses are governed by carrier dynamics, which is greatly influenced by temperature and corresponding phase structure due to the effects of inherently electron-phonon coupling. Notably, CPI NCs have been identified to adopt an unexpectedly stable cubic phase from room temperature to liquid helium temperature. Here, using in situ cryogenic electron diffraction measurements, it is unambiguously demonstrated that CPI NCs undergo consecutive cubic-tetragonal-orthorhombic phase transitions from 298 to 100 K. The corresponding temperature-dependent multiexcitonic dynamics are investigated in each phase by combining time-resolved photoluminescence and transient absorption spectroscopy. In addition to the temperature dependency, the lifetime of both excitons and biexcitons evidently depends on the phase structures of the CPI NCs, highlighting the crucial effect of crystal structure on the carrier dynamics. Moreover, the biexciton binding energy increases with higher crystal symmetry due to the decrease of the dielectric constant. The findings shed light on the structural phase transition and its relationship to the carrier dynamics in all-inorganic perovskite NCs, which provides critical insight into the structure-performance relationship in CPI NCs for promising applications in optoelectronic devices.</p>}},
author = {{Liu, Siyu and Geng, Huifang and Geng, Huaxiu and Huang, Zhuanzhuan and Deng, Shibin and Shen, Xi and Yu, Richeng and Zheng, Kaibo and Canton, Sophie E. and Fu, Xuewen}},
issn = {{1614-6832}},
keywords = {{biexcitons; cryogenic electron diffraction; CsPbI3 perovskite nanocrystals; multiexcitonic dynamics; phase transitions}},
language = {{eng}},
month = {{08}},
number = {{30}},
publisher = {{Wiley-Blackwell}},
series = {{Advanced Energy Materials}},
title = {{Probing the Multiexcitonic Dynamics in CsPbI<sub>3</sub> Nanocrystals across the Temperature-Induced Reversible Phase Transitions}},
url = {{http://dx.doi.org/10.1002/aenm.202301097}},
doi = {{10.1002/aenm.202301097}},
volume = {{13}},
year = {{2023}},
}