Doubly Stabilized Perovskite Nanocrystal Luminescence Downconverters

TL;DR

This paper presents a ligand-assisted copolymer nanoreactor synthesis method that produces highly stable perovskite nanocrystals with high quantum yields, suitable for use as stable luminescent downconverters in optoelectronic devices.

Contribution

The work introduces a double protection system combining polymer micelles and ligands to significantly enhance perovskite nanocrystal stability while maintaining high optical performance.

Findings

Achieved quantum yields up to 95% in stable perovskite NCs.

Demonstrated successful integration of NCs as downconverters on blue LEDs.

Enhanced resistance of NCs to water, heat, and UV light degradation.

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.