Near-Infrared-to-Visible Photon Upconversion with Efficiency Exceeding 21% Sensitized by InAs Quantum Dots.
J Am Chem Soc
; 146(26): 17618-17623, 2024 Jul 03.
Article
em En
| MEDLINE
| ID: mdl-38899905
ABSTRACT
Upconversion (UC) of incoherent near-infrared (NIR) photons to visible photons through sensitized triplet-triplet annihilation (TTA) shows great potential in solar energy harvesting, photocatalysis, and bioimaging. However, the efficiencies of NIR-to-visible TTA-UC systems lag considerably behind those of their visible-to-visible counterparts. Here, we report a novel NIR-to-yellow TTA-UC system with a record quantum yield (QY) of 21.1% (out of a 100% maximum) and a threshold intensity of 20.2 W/cm2 by using InAs-based colloidal quantum dots (QDs) as triplet photosensitizers. The key to success is the epitaxial growth of an ultrathin ZnSe shell on InAs QDs that passivates the surface defects without impeding triplet energy transfer (TET) from QDs to surface-bound tetracene. Transient absorption spectroscopy verifies efficient TET efficiency of more than 80%, along with sufficiently long triplet lifetime of tetracene molecules, leading to high-performance UC. Moreover, high UC QYs (>18%) remain when larger InAs-based QDsâof which the absorption peak is red-shifted by more than 50 nmâare used as sensitizers, indicating the great potential of InAs QDs to utilize NIR photons with lower energy.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Am Chem Soc
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China