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Abstract BackgroundResearch into perovskite nanocrystals (PNCs) has uncovered interesting properties compared to their bulk counterparts, including tunable optical properties due to size‐dependent quantum confinement effect (QCE). More recently, smaller PNCs with even stronger QCE have been discovered, such as perovskite magic sized clusters (PMSCs) and ligand passivated PbX2metal halide molecular clusters (MHMCs) analogous to perovskites. ObjectiveThis review aims to present recent data comparing and contrasting the optical and structural properties of PQDs, PMSCs, and MHMCs, where CsPbBr3PQDs have first excitonic absorption around 520 nm, the corresponding PMSCS have absorption around 420 nm, and ligand passivated MHMCs absorb around 400 nm. ResultsCompared to normal perovskite quantum dots (PQDs), these clusters exhibit both a much bluer optical absorption and emission and larger surface‐to‐volume (S/V) ratio. Due to their larger S/V ratio, the clusters tend to have more surface defects that require more effective passivation for stability. ConclusionRecent study of novel clusters has led to better understanding of their properties. The sharper optical bands of clusters indicate relatively narrow or single size distribution, which, in conjunction with their blue absorption and emission, makes them potentially attractive for applications in fields such as blue single photon emission.
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This content will become publicly available on June 11, 2026
Narrow Blue Emission from Cadmium Phosphide Clusters Enhanced through Phosphinate Ligation
The atomic precision of magic-sized clusters offers a route toward narrow emission by eliminating heterogeneous broadening. Herein, we report ultranarrow 467 nm blue emission from cadmium phosphide clusters with a 96 meV line width and as high as 26% photoluminescence quantum yield (PLQY) enabled by tightly bound, bidentate phosphinate ligands. They are obtained through postsynthetic ligand exchange from oleate-capped clusters. The phosphinate maintains the bidentate coordination motif, which does not disturb the metastability of the material but does induce a change in the surface dipole, causing a bathochromic shift in the emission from 457 to 467 nm, which is an optimal wavelength for blue emission. We find that the structure of the ligand tail can heavily influence PLQY and other aspects of the charge carrier dynamics. The ligand exchange protocol can be applied to the related cadmium arsenide clusters, resulting in a narrow 550 nm green emission with a 9% PLQY.
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- Award ID(s):
- 2107237
- PAR ID:
- 10621345
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- Nano Letters
- Volume:
- 25
- Issue:
- 23
- ISSN:
- 1530-6984
- Page Range / eLocation ID:
- 9410 to 9416
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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