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Ag₂ZnSnS₄-ZnS core-shell colloidal quantum dots: a near-infrared luminescent material based on environmentally friendly elements.

ABSTRACT: Low cost, multinary colloidal quantum dots (QDs) based on environmentally friendly elements, with bright, narrow-width, tunable near-infrared (NIR) luminescence are promising alternatives to Cd and Pb chalcogenide QDs for in vivo bio-imaging, LED and sensing applications. Herein, we demonstrate Pb/Cd free solution-processed colloidal luminescent Ag₂ZnSnS₄-ZnS (AZTS-ZnS) core-shell QDs with precise control over the ZnS shell thickness and thereby its optical properties. Unlike indium based multinary (I-III-VI group) core-shell QDs these nanocrystals show a narrow photoluminescence (PL) full width at half maximum (fwhm) of 105-110 meV in the first NIR window. By monitoring the starting AZTS core size, we achieve tunable emission over a small NIR window in these QDs with the best PL quantum yield (PLQY) of 17.4%.

SUBMITTER: Saha A

PROVIDER: S-EPMC8101413 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Ag2ZnSnS4-ZnS core-shell colloidal quantum dots: a near-infrared luminescent material based on environmentally friendly elements.

Saha Avijit A Konstantatos Gerasimos G

Journal of materials chemistry. C 20210406 17

Low cost, multinary colloidal quantum dots (QDs) based on environmentally friendly elements, with bright, narrow-width, tunable near-infrared (NIR) luminescence are promising alternatives to Cd and Pb chalcogenide QDs for in vivo bio-imaging, LED and sensing applications. Herein, we demonstrate Pb/Cd free solution-processed colloidal luminescent Ag2ZnSnS4-ZnS (AZTS-ZnS) core-shell QDs with precise control over the ZnS shell thickness and thereby its optical propertie ...[more]

PMID: 33996096

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