Stabilized CsPbBr₃ quantum dots in flower-like LYH matrix for high-performance white light-emitting diodes

Perovskite quantum dots (QDs) possess remarkable luminescent properties, making them highly promising for optoelectronic devices. However, their industrial applications are limited due to their poor stability in various environmental conditions. In this study, we present a novel approach to fabricate stabilized CsPbBr₃ QDs by incorporating them into a three-dimensional layered yttrium hydroxide (3D-LYH) matrix using a thermal injection method. The resulting 3D-LYH-CsPbBr₃ composites exhibit an impressive solid photoluminescence quantum yield (PLQY) of 84.34%. Additionally, it demonstrates excellent stability, retaining 65.64% of its initial PLQY even after 120 days of storage in a humid environment. Moreover, the composites exhibit a marginal decrease of only 20% in PL strength after undergoing four heating–cooling cycles ranging from 25 to 100 °C. This enhanced stability is attributed to the unique flower-like structure of the 3D-LYH matrix, which effectively stabilizes the CsPbBr₃ QDs. Furthermore, we successfully obtained white light-emitting diodes by spin-coating the 3D-LYH-CsPbBr₃ composites. The resulting white light achieves color coordinates of (0.310, 0.321) and a correlated color temperature of 6750 K. These advancements highlight the potential of LYH-based composite luminescent materials for applications in display and lighting devices.