Relatively Bright Intraband 5 μm Photoluminescence from HgSe/CdS Quantum Dot Films after Lead Halide Treatment
The 5 μm intraband photoluminescence (PL) from 200 nm thin films of n-doped mercury selenide/cadmium sulfide (HgSe/CdS) core/shell colloidal quantum dots reaches 0.2% apparent external efficiency, after solid-state ligand exchange with a solution of lead iodide (PbI<sub>2</sub>) and annealing at 140 °C. The PbI<sub>2</sub> treatment removes 95% of the C-H vibration absorption, but the PL increase is correlated with improved n-doping and not with organic ligand removal. The integrated emission intensity increases only by 20% upon cooling from 423 to 85 K. This suggests that multiphonon relaxation is not limiting the PL and that brighter emission should still be possible. PbI<sub>2</sub> treatment gave the brightest films, but PbBr<sub>2</sub> and PbCl<sub>2</sub> have similar effects.
Authors
- Augustin Caillas (ORCID: https://orcid.org/0009-0007-9075-9449)
- Rounak Naphade (ORCID: https://orcid.org/0000-0002-3504-8552)
- Philippe Guyot‐Sionnest (ORCID: https://orcid.org/0000-0003-0178-6255)
Institutions
- University of Chicago (US)
Publication Details
- Journal
- The Journal of Physical Chemistry Letters
- Published
- 2025-06-06
- DOI
- https://doi.org/10.1021/acs.jpclett.5c01021
- Primary Topic
- Quantum Dots Synthesis And Properties
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Basic Energy Sciences
- Air Force Research Laboratory