In Situ Confined Growth of Perovskite Nanocrystals within a Zirconium-Based Metal-Organic Framework via a Precoordination Strategy toward Stable White Light-Emitting Diodes.

Metal halide perovskite nanocrystals (PeNCs) have garnered significant interest for next-generation optoelectronics due to their exceptional optical properties, yet their practical application in white light-emitting diodes (WLEDs) is severely hampered by intrinsic instability and efficiency losses. While encapsulation within metal-organic frameworks (MOFs) has emerged as a promising strategy to enhance stability, conventional methods that confine preformed PeNCs within MOF pores often suffer from issues such as nanocrystal leaching, lack of precise spatial localization, and compromised structural characterization. To address these challenges, this work introduces a novel precoordination and in situ conversion strategy. We synthesized a stable zirconium-based MOF (Zr-bpydc) with nitrogen coordination sites to immobilize lead halide precursors. Subsequently, it was transformed into a highly pure PeNC phase within the microporous scaffold, resulting in the formation of the CsPbBr3@Zr-bpydc composite. The green-emitting CsPbBr3@Zr-bpydc composites and commercial blue (BaMgAl10O17:Eu2+) and red phosphors (K2SiF6:Mn4+) dispersed in commercial UV-chip (370 nm) WLEDs displayed excellent-quality white light with high color purity, relative CCT (8912 K), and high CRI (91.5), which highlights their potential in solid-state lighting systems.