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Perovskite CsPbX3 (X = Cl, Br, I) nanocrystals with advantages of high quantum yield, narrow emission peaks, and tunable fluorescence are considered as the next generation of light‐emitting sources. However, fluorescence degradation due to the poor stability of perovskite nanocrystals in moisture, high temperature, and illumination remains one of the greatest challenges in their further development. In this work, a fully dense coating strategy is proposed to improve the overall stability of perovskite nanocrystals, especially under high‐density laser irradiation. A mesoporous silica SiO2 layer is introduced to construct a stable coating for isolating the perovskite from external environment. To eliminate the pores of the CsPbX3@SiO2, an inorganic glass is also employed via solution‐combustion technique to generate a fully compact encapsulation for further stability promotion. The as‐prepared nanocrystal‐in‐glass composite exhibits efficient and stable fluorescence performance in luminous efficiency, chromaticity, and long‐term reliability in the conditions of thermal shock, humidity, and blue laser irradiation. With the integration of red/green/blue emitting nanocrystals, the color gamut of the white laser lighting source covers 134% of the National Television Standards Committee standard, providing exciting opportunity for high performance laser‐driven white light generation. [ABSTRACT FROM AUTHOR]

Rational design and fabrication of multicolor fluorescent sources represent one of the significant challenges in the development of high‐performance solid‐state lighting, tunable coherent lasing, and full‐color display technologies. However, generation of simultaneous multicolor emission, especially white light generation with a wide color gamut is usually beyond the ability of a single material. Heterogeneous structures made by combinations of red, green, and blue emission building blocks are bulky, inefficient, complicated, and costly. Here reported is a bottom‐up strategy to generate simultaneous multicolor emission with continuous tunability in a single monolithic material based on the "nanocrystals‐in‐glass composite" (NGC) architecture. In this approach, a self‐sustained low‐temperature solution combustion process enables homogeneous solvent dispersion and eventually stable immobilization of multiple nanocrystals in transparent matrix. With transparency of up to 80%, further demonstrated is drawing of fiber from the melt of these combustion‐processed NGC materials. The optical spectra of the as‐drawn glass fiber can be precisely tuned and clustering is effectively suppressed. Moreover, the NGC materials exhibit remarkable anti‐thermal quenching behavior at temperatures of up to 200 °C. The bottom‐up strategy for NGC provides a versatile platform for the fabrication of high‐performance multifunctional fiber‐based devices for advanced applications in lasers, illumination, displaying, and biophotonics. [ABSTRACT FROM AUTHOR]

• Monodisperse Cu 3 P nanoplates in situ grown on reduced graphene oxide (rGO). • Cu 3 P/rGO composite possessed a good overpotential for HER. • A low overpotentials of 144 mV at current density of 10 mA cm−2 was obtained. The monodisperse Cu 3 P nanoplate/reduced graphene oxide (rGO) composite was obtained by in situ growing Cu 3 P on the surface of rGO via the hydrophobic interaction in the colloidal solution. The monodisperse Cu 3 P nanoplates is about 55 nm due to the modification of hexadecylamine. The composite structure not only offered more catalytic active sites by Cu 3 P nanoplates, but also facilitated rapid electron transfer due to rGO for water splitting. The Cu 3 P/rGO showed a high hydrogen evolution reaction efficiency, which yielded low overpotentials of 144 mV at current density of 10 mA cm−2. [ABSTRACT FROM AUTHOR]

Conventional near-infrared luminescent phosphors activated by transition metal elements or rare earth activators were already widely reported. In this work, we develop a self-activated near-infrared luminescent phosphor with a typical double perovskite structure, which exhibits an emission at 650–750 nm under excitation at 365 nm. The origin of the desired luminescence in (Ca,Sr)LaMgTaO 6 compounds is attributed to the oxygen vacancies defects, oxygen interstitial defects and substitution defects and antioccupation defects. Thermal quenching of photoluminescence is undesirable with an integrated emission loss of 30–50% at 150 °C, which needs to be improved. This new series of near-infrared luminescent materials have potential applications in agricultural cultivations and bio-imaging materials. More importantly, we demonstrate a strategy by self-activation to realize near-infrared light. [ABSTRACT FROM AUTHOR]

Ce3+–Tb3+–Eu3+ triply doped Ba3KPO4(SO4)2 phosphors were synthesized and extensively studied. The luminescence properties, concentration effect and energy transfer (ET) mechanism of phosphors were studied in detail using the photoluminescence spectra and decay curves. The luminescent color of Ce3+–Tb3+–Eu3+ triply doped Ba3KPO4(SO4)2 phosphors can be tuned by adjusting the ET between different dopants. Spectroscopy studies demonstrate that Tb3+ acts as a bridge via Ce3+–Tb3+–Eu3+ ET in Ba3KPO4(SO4)2. The combined effects of energy-transfer on the emission color of Ce3+–Tb3+–Eu3+ show that the newly synthesized Ba3KPO4(SO4)2:Ce3+/Tb3+/Eu3+ phosphors can be used as a potential color converter with a large color gamut. [ABSTRACT FROM AUTHOR]