Charge Carrier Diffusion Dynamics in Multisized Quaternary Alkylammonium-Capped CsPbBr3 Perovskite Nanocrystal Solids
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389021%3A_____%2F21%3A00555266" target="_blank" >RIV/61389021:_____/21:00555266 - isvavai.cz</a>
Result on the web
<a href="https://pubs.acs.org/doi/pdf/10.1021/acsami.1c11676" target="_blank" >https://pubs.acs.org/doi/pdf/10.1021/acsami.1c11676</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/acsami.1c11676" target="_blank" >10.1021/acsami.1c11676</a>
Alternative languages
Result language
angličtina
Original language name
Charge Carrier Diffusion Dynamics in Multisized Quaternary Alkylammonium-Capped CsPbBr3 Perovskite Nanocrystal Solids
Original language description
CsPbBr3 quantum dots (QDs) are promising candidates for optoelectronic devices. The substitution of oleic acid ( OA) and oleylamine ( OLA) capping agents with a quaternary alkylammonium such as di-dodecyl dimethyl ammonium bromide (DDAB) has shown an increase in external quantum efficiency (EQE) from 0.19% (OA/OLA) to 13.4% (DDAB) in LED devices. The device performance significantly depends on both the diffusion length and the mobility of photoexcited charge carriers in QD solids. Therefore, we investigated the charge carrier transport dynamics in DDAB-capped CsPbBr3 QD solids by constructing a bi-sized QD mixture film. Charge carrier diffusion can be monitored by quantitatively varying the ratio between two sizes of QDs, which varies the mean free path of the carriers in each QD cluster. Excited-state dynamics of the QD solids obtained from ultrafast transient absorption spectroscopy reveals that the photogenerated electrons and holes are difficult to diffuse among small-sized QDs (4 nm) due to the strong quantum confinement. On the other hand, both photoinduced electrons and holes in large-sized QDs (10 nm) would diffuse toward the interface with the small-sized QDs, followed by a recombination process. Combining the carrier diffusion study with a Monte Carlo simulation on the QD assembly in the mixture films, we can calculate the diffusion lengths of charge carriers to be similar to 239 +/- 16 nm in 10 nm CsPbBr3 QDs and the mobility values of electrons and holes to be 2.1 (+/- 0.1) and 0.69 (+/- 0.03) cm(2)/V s, respectively. Both parameters indicate an efficient charge carrier transport in DDAB-capped QD films, which rationalized the perfect performance of their LED device application.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
20501 - Materials engineering
Result continuities
Project
<a href="/en/project/EF16_026%2F0008390" target="_blank" >EF16_026/0008390: Partnership for excellence in superprecise optics</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2021
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
ACS Applied Materials and Interfaces
ISSN
1944-8244
e-ISSN
1944-8252
Volume of the periodical
13
Issue of the periodical within the volume
37
Country of publishing house
US - UNITED STATES
Number of pages
9
Pages from-to
44742-44750
UT code for WoS article
000700877100087
EID of the result in the Scopus database
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