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arXiv · 2201.05472

Doubly Stabilized Perovskite Nanocrystal Luminescence Downconverters

Abstract

Halide perovskite nanocrystals (NCs) have emerged as a promising material for applications ranging from light-emitting diodes (LEDs) to solar cells and photodetectors. Still, several issues impede the realization of the nanocrystals' full potential, most notably their susceptibility to degradation from environmental stress. This work demonstrates highly stable perovskite nanocrystals (NCs) with quantum yields as high as 95 % by exploiting a ligand-assisted copolymer nanoreactor-based synthesis. The organic ligands thereby serve a dual function by enhancing the uptake of precursors and passivating the NCs. The polymer micelles and ligands thus form a double protection system, shielding the encapsulated NCs from water-, heat- and UV-light-induced degradation. We demonstrate the optoelectronic integrability by incorporating the perovskite NCs as spectrally pure downconverters on top of a deep-blue-emitting organic LED. These results establish a way of stabilizing perovskite NCs for optoelectronics while retaining their excellent optical properties.

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Qi Xue, Carola Lampe, Tassilo Naujoks, Kilian Frank, Moritz Gramlich, Markus Schoger, Willem Vanderlinden, Patrick Reisbeck, Bert Nickel, Wolfgang Brütting, Alexander Urban. 2022-01-13. Doubly Stabilized Perovskite Nanocrystal Luminescence Downconverters. https://arxiv.org/abs/2201.05472

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