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The MgO–Ga2O3–SiO2 glasses and glass‐ceramics samples doped with Eu2+/Mn2+/Er3+ and heated in reductive atmosphere were prepared by the sol–gel method. The structure, morphology and the luminescence properties were studied using X‐ray diffraction, high‐resolution transmission electron microscope, fluorescence spectra, and up‐conversion emission. The luminescence characteristics of doped ions could be influenced by temperature and matrix component. The characteristic emission of Mn2+, Eu2+ and Er3+ were seen and the energy transfer efficiency from Eu2+ to Mn2+ was enhanced as Mn2+ concentration was increased. In addition, the two‐photon process was determined for the Er3+‐doped samples. [ABSTRACT FROM AUTHOR]

The BaZrxSi3O7+2x:Eu2+/Eu3+ (2%, molar ratio) phosphors were prepared with adding different amounts of zirconium dioxide (ZrO2) (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) by a self‐reduction method under air conditions. X‐ray diffraction, photoluminescence properties, thermal quenching properties and luminescent lifetimes of the prepared samples were systematically analyzed. In BaZrxSi3O7+2x:Eu2+/Eu3+, both the 4f → 5d transitions of Eu2+ and sharp emissions assigned to 5D0 → 7FJ (J = 0, 1, 2, 3, 4) transitions of Eu3+ were observed. In addition, the results also reveal that the amount of ZrO2 affects the crystal structure, the self‐reduction process and further influences the relative intensity of Eu2+/Eu3+ in all samples. Therefore, the diverse emission colors can be obtained and modulated by controlling the content of ZrO2. The highlight of this work is that the white light emission is observed, when x is 0.4, 0.6, 0.8 and 1, respectively. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, MAl2SixO2x+4:Eu2+/Eu3+ (Eu2+ + Eu3+ = 2%, molar ratio; M = Mg, Ca, Sr, Ba; x = 0, 0.5, 1, 1.5, 2) phosphors with different SiO2 concentrations (the ratio of SiO2 to MAl2O4 is n%, n = 0, 50, 100, 150, 200, respectively) were prepared by high‐temperature solid‐state reaction under atmospheric air conditions. Their structures and photoluminescent properties were systematically researched. The results indicate that Eu3+ ions have been reduced and Eu2+ ions are obtained in air through the self‐reduction mechanism. The alkaline earth metal ions and doping SiO2 strongly affect the crystalline phase and photoluminescent properties of samples, including microstructures, relative intensity of Eu2+ to Eu3+, location of emission lines/bands. It is interesting and important that the emission color and intensities of europium‐doped various phosphors which consist of aluminosilicate matrices prepared under atmospheric air conditions could be modulated by changing the kinds of alkaline earth metal and the content of SiO2. [ABSTRACT FROM AUTHOR]

The BaZr x Si 3 O 7+2x :Eu 2+ /Eu 3+ (2%, molar ratio) phosphors were prepared with adding different amounts of zirconium dioxide (ZrO 2 ) (x = 0, 0.2, 0.4, 0.6, 0.8, and 1) by a self-reduction method under air conditions. X-ray diffraction, photoluminescence properties, thermal quenching properties and luminescent lifetimes of the prepared samples were systematically analyzed. In BaZr x Si 3 O 7+2x :Eu 2+ /Eu 3+ , both the 4f → 5d transitions of Eu 2+ and sharp emissions assigned to 5 D 0 → 7 F J (J = 0, 1, 2, 3, 4) transitions of Eu 3+ were observed. In addition, the results also reveal that the amount of ZrO 2 affects the crystal structure, the self-reduction process and further influences the relative intensity of Eu 2+ /Eu 3+ in all samples. Therefore, the diverse emission colors can be obtained and modulated by controlling the content of ZrO 2 . The highlight of this work is that the white light emission is observed, when x is 0.4, 0.6, 0.8 and 1, respectively., (© 2018 John Wiley & Sons, Ltd.)

In this paper, MAl 2 Si x O 2x+4 :Eu 2+ /Eu 3+ (Eu 2+ + Eu 3+ = 2%, molar ratio; M = Mg, Ca, Sr, Ba; x = 0, 0.5, 1, 1.5, 2) phosphors with different SiO 2 concentrations (the ratio of SiO 2 to MAl 2 O 4 is n%, n = 0, 50, 100, 150, 200, respectively) were prepared by high-temperature solid-state reaction under atmospheric air conditions. Their structures and photoluminescent properties were systematically researched. The results indicate that Eu 3+ ions have been reduced and Eu 2+ ions are obtained in air through the self-reduction mechanism. The alkaline earth metal ions and doping SiO 2 strongly affect the crystalline phase and photoluminescent properties of samples, including microstructures, relative intensity of Eu 2+ to Eu 3+ , location of emission lines/bands. It is interesting and important that the emission color and intensities of europium-doped various phosphors which consist of aluminosilicate matrices prepared under atmospheric air conditions could be modulated by changing the kinds of alkaline earth metal and the content of SiO 2 ., (Copyright © 2017 John Wiley & Sons, Ltd.)