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All‐inorganic CsPbX3 (X = Cl, Br, and I) perovskite nanocrystals (NCs) have great application prospects in many fields due to their excellent photoelectric properties. However, CsPbX3 NCs are extremely sensitive to water, heat, light, and oxygen, which leads to dramatic photoluminescence quenching and seriously restricts their future commercial applications. Herein, a novel, simple one‐step solution strategy for synthesizing high‐quality CsPbBr3 NCs was reported. By the combination of the hot‐injection process with the mesoporous template confinement effect of the KIT‐6 matrix, the space‐confined growth of NCs was precisely achieved. The CsPbBr3 NCs encapsulated by KIT‐6 (CsPbBr3@KIT‐6 composite) exhibited a uniform size, a high photoluminescence quantum yield (PLQY) of up to 82%, and a narrow full width at half‐maximum (FWHM) of 24 nm. Most importantly, CsPbBr3@KIT‐6 powder composites had dramatically enhanced light, thermal and water stability in comparison with colloidal CsPbBr3 NCs due to the dual protection of organic ligands and matrix templates. Ultimately, a white light‐emitting diode (LED) device was successfully fabricated by encapsulating a mixture of green‐emitting CsPbBr3@KIT‐6 composite and red‐emitting K2SiF6:Mn4+ phosphor onto a blue‐emitting InGaN LED chip. A color coordinate of (0.327, 0.337) and a wide color gamut of 128% NTSC well demonstrate their potential applications in lighting and display. [ABSTRACT FROM AUTHOR]

Glutathione (GSH) is generally used as an effective and sensitive tumor marker because its abnormal levels are associated with high free radical level in tumor. In this work, GSH could be easily detected by a kind of designed Eu‐based metal–organic frameworks (Eu‐MOFs, named Eu(DTBA)) fluorescent sensor. Due to the "antenna effect" of 4,4′‐dithiobenzoic acid (4,4′‐DTBA) ligands on Eu3+, Eu(DTBA) emits the strong characteristic red light of Eu3+ under ultraviolet excitation. Moreover, the emission intensity strongly depends on GSH concentrations. Thus, Eu(DTBA) can serve as a turn‐off fluorescent switch of GSH because its framework structure can easily be destroyed by GSH that leads to the fluorescence quenching. Remarkably, during sensing GSH, Eu(DTBA) has shown many appealing performances, such as broad a response window (0–20 mM), fast response (3 min), high sensitivity (LOD = 0.35 µM), and excellent anti‐interference ability. The real bioimaging application has demonstrated that the reported Eu(DTBA) can be used as an excellent bioimaging agent to successfully distinguish tumor cells from normal cells in clinical diagnosis. [ABSTRACT FROM AUTHOR]

Eu2+-doped AlN-polytypoids (8H, 15R, 12H, and 21R) were successfully synthesized by nitrogen-gas-pressure sintering. The phosphors show intense blue emissions under the electron beam excitation. All the polytypoid phosphors exhibit relatively a smaller degradation in luminance and a higher thermal stability in comparison to the oxide counterparts. Among the polytypoids, 12H has no luminance saturation, and shows a brightness of 40 cd/m2 at 3 kV and 100 μA. These results indicate that Eu2+-doped AlN-polytypoids could also be used as blue phosphors for FEDs. [ABSTRACT FROM AUTHOR]