Phosphor in glasses with Pb-free silicate glass powders as robust color-converting materials for white LED applications

Phosphor-in-glass (PiG) typed robust color converters were fabricated using Pb-free silicate glasses for high-power white LED applications. SiO₂-B₂O₃-RO(R=Ba,Zn) glass powder showed good sintering behavior and high visible transparency under the sintering condition of 750?°C for 30?min without noticeable interaction with phosphors. By simply changing the thickness of the PiG plate or mixing ratio of glass to Y₃Al₅O₁₂:Ce³⁺ phosphor, CIE chromaticity coordinates of the LED can be easily controlled. Enhanced thermal quenching property of PiG compared to phosphor with conventional silicone resin suggests its prominent feasibility for high-power/high-brightness white LEDs.     

Effects of electron irradiation on the properties of GZO films deposited with RF magnetron sputtering

Transparent conductive GZO films were deposited on polycarbonate substrates by electron beam assisted radio frequency (RF) magnetron sputtering and then the influence of electron irradiation on the structural, optical and electrical properties of GZO films was investigated by using X-ray diffractometry, UV-vis spectrophotometry, four point probes, atomic force microscopy and UV photoelectron spectroscopy. Sputtering power was kept constant at 3 W/cm² during deposition, while electron irradiation energy varied from 450 to 900 eV.Electron irradiated GZO films show larger grain sizes than those of films prepared without electron irradiation, and films irradiated at 900 eV show higher optical transmittance in the visible wavelength region and lower sheet resistance (120 Ω/□) than other films. The work-function is also increased with electron irradiation energy. The highest work-function of 4.4 eV was observed in films that were electron irradiated at 900 eV.     

Influence of silver nanoclusters on formation of PbS quantum dots in glasses

Heat-treatment was used to precipitate PbS quantum dots (QDs) in silicate glasses doped with different amounts of Ag₂O, and the influence of Ag₂O on QDs was investigated. Under given heat-treatment conditions, the absorption coefficients and photoluminescence intensities of PbS QDs increased with the addition of Ag₂O. Ag clusters formed by thermal treatment nucleated formation of PbS QDs in glasses.     

Compositional dependences on the mechanism of upconversion in Nd3+/Tm3+ co-doped chalcohalide glasses

Mechanisms of the compositional dependence of blue emission from Nd³⁺/Tm³⁺ co-doped Ge–Ga–S–CsBr chalcohalide glasses were investigated. The blue upconversion emissions (centered at 475 nm) due to the Tm³⁺: ¹G₄ → ³H₆ transition decreased as the CsBr/Ga ratio in glasses while the other upconversion emissions from the Nd³⁺ ions increased. Changes in the local environment of rare-earth ions incurred by the CsBr addition significantly increased the excited state absorption within Nd³⁺ ions. This resulted in the decrease in the Nd³⁺ → Tm³⁺ energy transfer rates that led to the large decrease in blue upconversion emission.     

H2O influence evaluating and mid-IR fluorescence quenching in Tm3+-doped GeGaSCsI chalcohalide glasses

This work presents a detailed study on near-infrared and mid-infrared fluorescence emissions with five sets of Tm³⁺-doped 75GeS₂–15Ga₂S₃–10CsI chalcohalide glass. They are prepared in normal or water drying process. Based on the diffusion-limited relaxation calculation, a detailed investigation is put forward to obtain efficient near-infrared or mid-infrared fluorescence emissions of Tm³⁺ on the effect of H₂O on the Tm³⁺ fluorescence. Detailed investigations are given to the interacted energy transferring processes between rare-earth, impurities and vibrating phonons with the appearance of fluorescence quenching, along with Tm³⁺, H₂O concentrations varying and energy gaps forming. The radioactive properties are analyzed using compensated diffusion-limited relaxation calculation method, and the near-IR and mid-IR fluorescence properties are evaluated in detail with experimental and theoretical analysis.     

Optical properties of PbSe quantum dots doped in borosilicate glass

PbSe quantum dots (QDs) were synthesized in borosilicate glass and their optical properties were investigated. The typical quantum confinement effects were clearly observed from the absorption when the average radii of the QDs changed from 1.7 to 3.1 nm. Photoluminescence from PbSe QDs was achieved in 1.1–2.2 μm wavelength region that covers the entire fiber-optic telecommunication window. Borosilicate glasses containing controlled size of PbSe QDs provide potentials for the fiber-optic amplifiers.     

Radial Fourier multipliers in high dimensions

Given a fixed p≠2, we prove a simple and effective characterization of all radial multipliers of FL^p( mathbbR^d ) mathcal{F}{L^p}left( {{mathbb{R}^d}} right) , provided that the dimension d is sufficiently large. The method also yields new L ^q space-time regularity results for solutions of the wave equation in high dimensions.     

Highly Selective Detection of Al3+ by Carboxamide-Based Fluorescent Chemosensor

We designed a carboxamide-based fluorescent chemosensor HTPQ ((E)-2-(((8-hydroxy-2,3,6,7-tetrahydro-1H,5H-pyrido[3,2,1-ij]quinolin-9-yl)methylene)amino)thiophene-3-carboxamide) for detecting Al³⁺. HTPQ could probe Al³⁺ by fluorescence enhancement. Limit of detection for Al³⁺ toward HTPQ was 1.4 μM. Binding of HTPQ to Al³⁺ was determined to be a 1:1 ratio with the analysis of Job plot and ESI-mass. In addition, HTPQ was able to detect Al³⁺ using the test strip by fluorescent variation. The sensing process of Al³⁺ by HTPQ was presented by UV–vis titration, ESI–MS, Job plot, ¹H NMR titration and DFT calculation.