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Zero-dimensional lead-free metal halides Cs3Cu2X5 (X = Cl, Br, and I) have attracted much attention in recent years due to their unique structure, photoelectric properties and environment-friendly nature; unfortunately they are sensitive to humidity. Herein, Cs3Cu2I5 nanocrystals (NCs) were successfully precipitated in situ within glass using the methods of melt quenching and heat treatment (Cs3Cu2I5 glass ceramic). The optical characterization and morphological characterization provide evidence for the successful in situ precipitation of the Cs3Cu2I5 glass ceramic, and the photoluminescence quantum yield (PLQY) is as high as 63.3%. The water stability of Cs3Cu2I5 NCs is greatly improved due to the inorganic glass matrix, and the fluorescence intensity remains largely unchanged for 30 days. The Cs3Cu2I5 glass ceramic endows Cs3Cu2I5 NCs with a wider range of application areas. Finally, by constructing an X-ray imaging system using Cs3Cu2I5 glass ceramics, springs in opaque samples were observed to be visible, demonstrating the great potential of Cs3Cu2I5 glass ceramics with long-term stability for X-ray detection imaging. [ABSTRACT FROM AUTHOR]

Silicon (Si) photodetectors (PDs) have attracted more attention due to their wide applications, but are limited by their extremely weak ultraviolet (UV) photo‐response. Herein, Dy3+‐CsPbCl2Br1 nanocrystals glass (Dy3+‐CPCB NCsG) is synthesized in borosilicate glass by traditional melt‐quenching. The doping of Dy3+ exceedingly improves the PL intensity of CsPbCl2Br1 nanocrystals glass (CPCB NCsG) with enhancing photoluminescence quantum yield from 8.0% to 30.2%, ascribed to the improved crystallinity and reduced defects. Meanwhile, the stability of CPCB NCsG exposed to air, light, and high temperature is largely boosted. After integrating with Dy3+‐CPCB NCsG, the responsivity, external quantum efficiency, detectivity, and stability of Si PDs are significantly enhanced. The responsivity (R) of Si PDs‐5% Dy3+‐CPCB NCsG is 0.006 A W−1 at 320 nm, which is sixfold higher than that of bare Si PDs. This work develops a blue Dy3+‐CPCB NCsG, which has great potential as a new luminescent material for the next generation of Si PDs. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (Au NPs) doped monolithic and transparent sodium borosilicate glass has been synthesized by both sol-gel and atmosphere control heat treatment methods. Fourier transform infrared (FTIR) spectra in the wavenumber range of 400 to 4000 [cm.sup.-1] were applied to collect variation information of surface groups of the samples in the sintering process. The microstructure of Au NPs in the glass was characterized by means of X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and high-resolution TEM (HRTEM). Meanwhile, the linear optical properties of the glass were analyzed by UV-vis spectrometer between the wavelength of 300 and 1000 nm, and a broad absorption band around 600 nm was observed. The third-order nonlinear optical properties of the glass were investigated by using Z-scan technique at the wavelength of 800 nm, pulse duration of 190 fs, and repetition rate of 20 Hz. The glass showed saturable absorption and self-focusing non-linear refraction, and the optical nonlinear susceptibility [X.sup.(3)] was estimated to be 1.7 x [10.sup.-14] esu, with the single-pulse energy of [micro]J. Keywords Au nanoparticles * Sol-gel * Sodium borosilicate glass * Third-order nonlinearity, Introduction To meet the increasing demand of information, new optical and optoelectronic technologies are required, and the ultrafast all-optical switches are considered to play an important role in the next [...]

High efficient lead halide perovskites with wide-color gamut properties have emerged as new candidates for backlight displays. However, the toxicity of lead and the instability of halide perovskites greatly limit their practical applications. Herein, the luminescent powders of [(CH3)4N]2MnBr4 and [(CH3)4N]MnBr3 were synthesized via a simple yet robust solvent evaporation method. [(CH3)4N]2MnBr4 with tetrahedral coordination Mn2+ and [(CH3)4N]MnBr3 with octahedral coordination Mn2+ show green at 517 nm and red emission peaks at 620 nm, respectively, originating from the 4T1-6A1 transition of Mn2+. To enhance optical of manganese halide via effective alloying, Zn2+-doped [(CH3)4N]2MnBr4 was successfully prepared, and the quantum efficiency of [(CH3)4N]2Mn0.6Zn0.4Br4 was as high as 65%. Furthermore, [(CH3)4N]2Mn0.6Zn0.4Br4 exhibits better optical and thermal stability compared to [(CH3)4N]2MnBr4. [(CH3)4N]2Mn0.6Zn0.4Br4@CsPbBr1.2I1.8 light conversion films with different green-to-red ratios are placed in backlight display devices, and their color gamut exceeds 106% of the National Television Standards Committee (NTSC) 1953 standard, which is superior to the currently reported Mn-based perovskite. This work broadly shows that the [(CH3)4N]2Mn0.6Zn0.4Br4 will provide effective route to fabricate stable and high-performance lead-free liquid crystal displays. [ABSTRACT FROM AUTHOR]

Solid‐state white lighting applications with high brightness, low power consumption and long operating life have gradually dominated the modern industrial illumination market. For applications in white light‐emitting diodes (WLEDs) and white‐lighting laser diodes (WLDs), Phosphor‐in‐Glass (PiG), owing to its facile process, high efficiency and excellent chromaticity tunability, stands out as an optimal choice among various types of color converters. Currently, research in yellow‐emitting Y3Al5O12:Ce3+ (YAG: Ce) phosphors combined with different glass system has reached a mature stage and the poor illumination is a major bottleneck. Moreover, to realize high‐quality white lighting, exploiting full‐color PiGs is of great importance for its commercialization. Herein, the multicolour PiGs their successfully obtained by deliberately matching different color‐emitting phosphors with the glass matrix. Glass composition selection rules for specific phosphors their proposed based on investigations of glass protection mechanism and the corrosion reaction between phosphors and glass matrix. In addition, an astonishing YAG: Ce PiG phenomenon (zero thermal quenching) is founded and discussed. As for practical applications, high‐quality 5‐W chip‐on‐board (COB) WLEDs their constructed by utilizing simple matches of colorful PiGs. Assembled WLDs modules also rendered a high‐efficiency and stable lighting source. These results dramatically inspire the development of high‐quality solid‐state white lighting applications. [ABSTRACT FROM AUTHOR]

Phosphor‐in‐glass (PiG) film has been proposed as an ideal color converter in laser diodes (LDs) lighting for its advantages of outstanding thermal conductivity (TC) and superior efficiency. Herein, yellow‐emitting Y1.31Ce0.09Gd1.6Al5O12 (Ce: GdYAG)‐PiG composite films are successfully elaborated through a practical blade‐coating approach. Systematical studies are performed on its microstructure, thermal stability, and luminescence performance pumped by LDs. Noteworthy, the highest internal quantum efficiency of film (94.2%) retains 97.1% of the raw phosphors (97%). Particularly, by further introducing micrometer BN with high TC as light scattering center to enhance heat dissipation and increase porosity, the thermal and optical properties of the sample are greatly improved. The luminescence intensity of the sample at 423 K is increased to 1.8 times that at 298 K. The thermal diffusion (TD) and TC of the sample are increased from 1.571 to 4.227 mm2 s−1 and 6.4 to 13.0 W m−1 K−1, respectively. At the same time, the maximum saturation threshold under laser irradiation of Ce: GdYAG + micrometer BN composite film is raised from 3.12 to 5.42 W mm−2 and 260.6 to 354.1 lm, respectively. The combination of excellent optical and thermal performances, coupled with facile and low‐cost synthetic strategy, could push forward the practical application in solid‐state laser lighting. [ABSTRACT FROM AUTHOR]