Spatially resolved fluorescence of caesium lead halide perovskite supercrystals reveals quasi-atomic behavior of nanocrystals
arXiv:2109.05502 · doi:10.1038/s41467-022-28486-3
Abstract
We correlate spatially resolved fluorescence (-lifetime) measurements with X-ray nanodiffraction to reveal surface defects in supercrystals of self-assembled caesium lead halide perovskite nanocrystals and study their effect on the fluorescence properties. Upon comparison with density functional modelling, we show that a loss in structural coherence, an increasing atomic misalignment between adjacent nanocrystals, and growing compressive strain near the surface of the supercrystal are responsible for the observed fluorescence blueshift and decreased fluorescence lifetimes. Such surface defect-related optical properties extend the frequently assumed analogy between atoms and nanocrystals as so-called quasi-atoms. Our results emphasize the importance of minimizing strain during the self-assembly of perovskite nanocrystals into supercrystals for lighting application such as superfluorescent emitters.
arXiv comment61 pages, 34 figures
References in corpus (10)
- CP2K: An Electronic Structure and Molecular Dynamics Software Package -- Quickstep: Efficient and Accurate Electronic Structure Calculations
- Extraordinary room-temperature photoluminescence in WS2 monolayers
- Superfluorescence from Lead Halide Perovskite Quantum Dot Superlattices
- Efficient solution of Poisson's equation with free boundary conditions
- Quasicrystalline Nanocrystal Superlattice with Partial Matching Rules
- Superabsorption of light via quantum engineering
- Temporal Evolution of Self-Assembled Lead Halide Perovskite Nanocrystal Superlattices: Effects on Photoluminescence and Energy Transfer
- Quantifying Angular Correlations between the Atomic Lattice and Superlattice of Nanocrystals Assembled with Directional Linking
- Spatially resolved fluorescence of caesium lead halide perovskite supercrystals reveals quasi-atomic behavior of nanocrystals
- Edge optical scattering of two-dimensional materials