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Controlled nucleation and slow growth endow blue emitting CsPbX3 nanocrystals (NCs) with bright photoluminescence (PL), which is crucial needed in luminescent devices. In this paper, a low‐temperature injection synthesis method is developed to control nucleation and the growth process by decreasing the reaction rate of ions, thereby controlling the morphologies of CsPbX3 NCs in clusters, nanorods (NRs), nanoplates (NPLs), and nanocubes by adjusting precursors, ligands, and injection parameters. CsPbX3 NCs exhibit excellent PL properties such as high quantum confinement effect. The PL peak wavelengths of CsPbBr3 NPLs and NRs are at 451 and 467 nm, respectively, in which their full width at half maximum (FWHM) of PL spectra is 22 and 12 nm, while their PL efficiencies are 65 and 74%, respectively. The method is further used to create CsPbI3 and CsPbCl3. CsPbI3 NPLs and NRs reveal PL peaks at 590 and 600 nm and PL efficiencies of 56% and 60%, respectively. These NCs exhibit excellent stability against ultraviolet light irradiation. A color conversion layer for white light‐emitting diodes is fabricated using these highly bright NCs. A Commission Internationale d'Eclairage color coordinate of (0.31,0.33) is located at the white light region specified by Rec.2020 standard, and the color temperature reaches 6189 K. [ABSTRACT FROM AUTHOR]

Infrared (IR) emitted Quantum Dots (QDs) are fascinating materials with the unique feature of energy levels engineering based on ligand exchange. In this work, the ligand of QDs is modified to form the charge transport layer of IR light‐emitting diodes (LEDs). The corresponding IRLEDs fabricated with all QDs materials can obtain electroluminescence (EL) peak of 1200 nm, including the wide full width at half maximum (FWHM), and an EQE of 4.5%. [ABSTRACT FROM AUTHOR]

CsPbBr 3 @Cs 4 PbBr 6 hexagonal NCs with a bright photoluminescence (PL) peak of 456 nm are created through the dissolution-recrystallization of CsPbBr 3 nanoplatelets. Small CsPbBr 3 nanocrystals are encapsulated in hexagonal Cs 4 PbBr 6 during recrystallization to form a core-shell structure and keep high brightness and stability. The recrystallization kinetics is systematically investigated to explore the roles of methyl acetate, oleylamine, and n-hexane. Result further indicates that core/shell NCs remained high PL under a variety of harsh conditions (e.g., light irradiation and heat treatment) because of Cs 4 PbX 6 shell and the controlling of recrystallization. Their initial PL intensity is remained after 4 months of storage under ambient conditions and continuous exposure to UV lamp for 180 min. The bright PL is also maintained even treatment at 120 °C. To indicate the universality of this synthesis method, CsPbX 3 @Cs 4 PbX 6 hexagonal NCs with different emission colors are fabricated by changing temperature, solvent viscosity, and precursors (e,g, oleylamine and halogens). These core-shell samples reveal bright and stable green, orange, and red PL. Because of its high stability, the core/shell NCs are dispersed in flexible films to create diverse patterns. The films also exhibit high brightness and excellent stability. This strategy opens a novel avenue for the application of perovskite nanomaterials in the display field., (© 2024 Wiley‐VCH GmbH.)