A Water-Free In Situ HF Treatment for Ultrabright InP Quantum Dots
© 2022 The Authors. Published by American Chemical Society.
Veröffentlicht in: | Chemistry of materials : a publication of the American Chemical Society. - 1998. - 34(2022), 22 vom: 22. Nov., Seite 10093-10103 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2022
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Zugriff auf das übergeordnete Werk: | Chemistry of materials : a publication of the American Chemical Society |
Schlagworte: | Journal Article |
Zusammenfassung: | © 2022 The Authors. Published by American Chemical Society. Indium phosphide quantum dots are the main alternative for toxic and restricted Cd-based quantum dots for lighting and display applications, but in the absence of protecting ZnSe and/or ZnS shells, InP quantum dots suffer from low photoluminescence quantum yields. Traditionally, HF treatments have been used to improve the quantum yield of InP to ∼50%, but these treatments are dangerous and not well understood. Here, we develop a postsynthetic treatment that forms HF in situ from benzoyl fluoride, which can be used to strongly increase the quantum yield of InP core-only quantum dots. This treatment is water-free and can be performed safely. Simultaneous addition of the z-type ligand ZnCl2 increases the photoluminescence quantum yield up to 85%. Structural analysis via XPS as well as solid state and solution NMR measurements shows that the in situ generated HF leads to a surface passivation by indium fluoride z-type ligands and removes polyphosphates, but not PO3 and PO4 species from the InP surface. With DFT calculations it is shown that InP QDs can be trap-free even when PO3 and PO4 species are present on the surface. These results show that both polyphosphate removal and z-type passivation are necessary to obtain high quantum yields in InP core-only quantum dots. They further show that core-only InP QDs can achieve photoluminescence quantum yields rivalling those of InP/ZnSe/ZnS core/shell/shell QDs and the best core-only II-VI QDs |
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Beschreibung: | Date Revised 29.11.2022 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 0897-4756 |
DOI: | 10.1021/acs.chemmater.2c02800 |