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Measurement of ligand coverage on cadmium selenide nanocrystals and its influence on dielectric dependent photoluminescence intermittency
journal contribution
posted on 2023-06-09, 18:05 authored by Aidan Fisher, Mark Osborne, Iain Day, Guillermo Lucena AlcaldePhotoluminescent quantum dots are used in a range of applications that exploit the unique size tuneable emission, light harvesting and quantum efficient properties of these semiconductor nanocrystals. However, optical instabilities such as photoluminescence intermittency, the stochastic switching between bright, emitting states and dark states, can hinder quantum dot performance. Correlations between this blinking of emission and the dielectric properties of the nanoenvironment between the quantum dot interface and host medium, suggest surface ligands play a role in modulating on-off switching rates. Here we elucidate the nature of the cadmium selenide nanocrystal surface, by combining magic angle spinning NMR and x-ray photoelectron spectroscopy to determine ligand surface densities, with molecular dynamics simulation to assess net ligand filling at the nanocrystal interface. Results support a high ligand coverage and are consistent with photoluminescence intermittency measurements that indicate a dominant contribution from surface ligand to the dielectric properties of the local quantum dot environment.
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Publication status
- Published
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- Published version
Journal
Communications ChemistryISSN
2399-3669Publisher
Nature ResearchExternal DOI
Issue
63Volume
2Page range
1-9Department affiliated with
- Chemistry Publications
Full text available
- Yes
Peer reviewed?
- Yes
Legacy Posted Date
2019-06-17First Open Access (FOA) Date
2019-06-17First Compliant Deposit (FCD) Date
2019-06-14Usage metrics
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