Environmentally stable luminescent perovskite nanocrystals passivated and encapsulated by siloxane hybrids enabling reliable color-converted organic light-emitting diodes

Abstract

Organic-inorganic hybrid perovskite nanocrystals (PNCs), have superior optical properties that meet the high color standard of Rec. 2020, but poor environmental instability, which impedes their practical applications as light emitters in displays. Here, we report exceptionally stable PNC-incorporated color-converting material that, and that maintains its luminescence in various harsh environments. Our main approach is to use two kinds of siloxane hybrid materials: a passivating ligand on the surface of PNCs (M-PNC) and an encapsulating matrix (MP-SH); they induce significantly improved stability against moisture, oxygen, and light. The MP-SH film (M-PNC encapsulated by siloxane hybrid) was stable for 100 d in water, air at 85 degrees C with 85% relative humidity, various polar solvents, and continuous blue light irradiation without any additional protecting layer. Furthermore, we investigate reversible optical property healing characteristics that are induced by water-induced defect passivation mechanism, suppressing non-radiative recombination in perovskite crystals. We demonstrate a color-converted organic light-emitting diode that uses MP-SH and that has excellent optical characteristics and operating reliability. This approach to increasing the environmental stability of PNCs provides great potential toward commercialization of PNCs for use in stable color-converting layers of displays.