Abstract
We have synthesized the first reported example of quantum confined high entropy (HE) nanoparticles, using the lanthanide oxysulfide, Ln2SO2, system as the host phase for a equimolar mixture of Pr, Nd, Gd, Dy and Er. A uniform HE phase was achieved via the simultaneous thermolysis of a mixture of lanthanide dithiocarbamate precursors in solution. This was confirmed by powder X-ray diffraction and high-resolution scanning transmission electron microscopy, with energy dispersive X-ray spectroscopic mapping confirming the uniform distribution of the lanthanides throughout the particles. The nanoparticle dispersion displayed a significant blue shift in the absorption and photoluminescence spectra relative to our previously reported bulk sample with the same composition, with an absorption edge at 330 nm and a λmax at 410 nm compared to the absorption edge at 500 nm and a λmax at 450 nm in the bulk, which is indicative of quantum confinement. We support this postulate with experimental and theoretical analysis of the band gap energy as a function of strain and surface effects (ligand binding) and calculation of the Bohr exciton radius for the end member compounds.
Original language | English |
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Pages (from-to) | 8045–8051 |
Journal | Nano Letters |
Early online date | 4 Oct 2022 |
DOIs | |
Publication status | Published - 26 Oct 2022 |
Research Beacons, Institutes and Platforms
- Photon Science Institute
- Henry Royce Institute