Controlled synthesis of highly stable lead-free bismuth halide perovskite nanocrystals : tructures and photophysics
(2023) In SCIENCE CHINA Materials 66(5). p.2079-2089- Abstract
Recently, cesium bismuth halide perovskites have emerged as potential substitutes to their counterparts, cesium lead halide perovskites, owing to their low toxicity. However, the photophysics of cesium-bismuth halides nanocrystals (NCs) have not yet been fully rationalized because their structures remain highly debated. The ultraviolet-visible (UV-vis) absorption along with other photophysical properties such as the nature and lifetime of the excited states vary considerably across the previous reports. Here, we successfully synthesize pure Cs3BiBr6 and Cs3Bi2Br9 NCs via a modified hot-injection method, where the structure can be easily controlled by tuning the reaction temperature.... (More)
Recently, cesium bismuth halide perovskites have emerged as potential substitutes to their counterparts, cesium lead halide perovskites, owing to their low toxicity. However, the photophysics of cesium-bismuth halides nanocrystals (NCs) have not yet been fully rationalized because their structures remain highly debated. The ultraviolet-visible (UV-vis) absorption along with other photophysical properties such as the nature and lifetime of the excited states vary considerably across the previous reports. Here, we successfully synthesize pure Cs3BiBr6 and Cs3Bi2Br9 NCs via a modified hot-injection method, where the structure can be easily controlled by tuning the reaction temperature. The UV-vis absorption spectrum of the pure Cs3Bi2Br9 NCs features two characteristic peaks originating from the absorption of the first exciton and second exciton, respectively, which ultimately clarifies the debate in the previous reports. Using femtosecond transient absorption spectroscopy, we systematically investigate the excited state dynamics of the Cs3Bi2Br9 NCs and reveal that the photoexcited carriers undergo a self-trapping process within 3 ps after excitation. More intriguingly, the Cs3Bi2Br9 NCs prepared by this method show much better photostability than those prepared by the ligand-assisted reprecipitation process. Photodetectors based on these Cs3Bi2Br9 NCs show a sensitive light response, demonstrating the definite potential for breakthrough optoelectronic applications. [Figure not available: see fulltext.].
(Less)
- author
- organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- bismuth perovskites, hot injection, lead-free perovskites, nanocrystals, photostability
- in
- SCIENCE CHINA Materials
- volume
- 66
- issue
- 5
- pages
- 2079 - 2089
- publisher
- Science in China Press
- external identifiers
-
- scopus:85145919994
- ISSN
- 2095-8226
- DOI
- 10.1007/s40843-022-2299-6
- language
- English
- LU publication?
- yes
- id
- 18dee2bb-5e66-43ce-a206-7841a104419d
- date added to LUP
- 2023-02-17 10:06:11
- date last changed
- 2023-12-02 20:16:24
@article{18dee2bb-5e66-43ce-a206-7841a104419d, abstract = {{<p>Recently, cesium bismuth halide perovskites have emerged as potential substitutes to their counterparts, cesium lead halide perovskites, owing to their low toxicity. However, the photophysics of cesium-bismuth halides nanocrystals (NCs) have not yet been fully rationalized because their structures remain highly debated. The ultraviolet-visible (UV-vis) absorption along with other photophysical properties such as the nature and lifetime of the excited states vary considerably across the previous reports. Here, we successfully synthesize pure Cs<sub>3</sub>BiBr<sub>6</sub> and Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub> NCs via a modified hot-injection method, where the structure can be easily controlled by tuning the reaction temperature. The UV-vis absorption spectrum of the pure Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub> NCs features two characteristic peaks originating from the absorption of the first exciton and second exciton, respectively, which ultimately clarifies the debate in the previous reports. Using femtosecond transient absorption spectroscopy, we systematically investigate the excited state dynamics of the Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub> NCs and reveal that the photoexcited carriers undergo a self-trapping process within 3 ps after excitation. More intriguingly, the Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub> NCs prepared by this method show much better photostability than those prepared by the ligand-assisted reprecipitation process. Photodetectors based on these Cs<sub>3</sub>Bi<sub>2</sub>Br<sub>9</sub> NCs show a sensitive light response, demonstrating the definite potential for breakthrough optoelectronic applications. [Figure not available: see fulltext.].</p>}}, author = {{Geng, Huifang and Huang, Zhuanzhuan and Geng, Huaxiu and Liu, Siyu and Naumova, Maria A. and Salvia, Raffaele and Chen, Siqi and Wei, Junli and Zhang, Lifu and Zou, Xianshao and Lin, Weihua and Cai, Xinyi and Yuan, Mingjian and Hu, Zhenpeng and Shen, Xi and Yu, Richeng and Zheng, Kaibo and Canton, Sophie E. and Fu, Xuewen}}, issn = {{2095-8226}}, keywords = {{bismuth perovskites; hot injection; lead-free perovskites; nanocrystals; photostability}}, language = {{eng}}, number = {{5}}, pages = {{2079--2089}}, publisher = {{Science in China Press}}, series = {{SCIENCE CHINA Materials}}, title = {{Controlled synthesis of highly stable lead-free bismuth halide perovskite nanocrystals : tructures and photophysics}}, url = {{http://dx.doi.org/10.1007/s40843-022-2299-6}}, doi = {{10.1007/s40843-022-2299-6}}, volume = {{66}}, year = {{2023}}, }