Study On The Structure And The Luminescent Properties Of The Rare Earth-doped B₂O₃-ZnO-BaO-SiO₂-Al₂O₃ Glasses

Due to its good luminescence performance, rare earth doped luminescent glass can be a very good alternative to the traditional phosphor to make LED encapsulation shell. In these work, TiO₂, Eu₂O₃ and Ag/Eu₂O₃ doped B₂O₃-ZnO-BaO-SiO₂-Al₂O₃ glasses were prepared by the technique of oxide high-temperature melting, the influence of these three-group on the structure, crystallization capacity, micro-morphology and luminescent properties of the glasses were studied. The main contents are as follows:?1? TiO₂ doped B₂O₃-ZnO-BaO-SiO₂-Al₂O₃ glasses were prepared by the technique of oxide high-temperature melting, FTIR spectra showed that with the addition of TiO₂, [BO3] gradually transforms into [BO4] and the network structure of glasses were enhanced. When TiO₂ content exceeds 7 mol%, as the network intermediate, TiO₂ begins to enter into the glass network as [TiO4]. DTA and XRD displayed that TiO₂, as the nucleating agent, can significantly reduce the crystallization temperature, enhance the crystallization tendency and promote the precipitation of rutile phase in the glass.?2? Eu₂O₃ doped B₂O₃-ZnO-BaO-SiO₂-Al₂O₃ glasses were prepared by the technique of oxide high-temperature melting, FTIR spectra showed that with the low addition of Eu₂O₃, [BO3] gradually transforms into [BO4] and the network structure of glasses were enhanced. When Eu₂O₃ content reaches 7 mol%, [BO4] transforms into [BO3], which makes the structure of glasses become unstable. DTA and XRD display that Eu₂O₃ can significantly increase the Tg and Tc of the glasses, but to some extent, it can enhance the crystallization ability of glass and affect the precipitation of Zn4B6O13 phase in the glass. Photoluminescence Spectrum of the glasses match the character emission peaks and characte excitation peaks of Eu3+ ion, and the quenching concentration is 5 mol%, When the excitation wavelength is 396 nm, it has a quite strong red emission, when it is annealed at 730 oC for 10 h, the luminous intensity is 2.3 times than that without annealing.?3? Selection of 5 mol% Eu₂O₃ doping system with the best luminous performance, Ag/Eu₂O₃ doped B₂O₃-ZnO-BaO-SiO₂-Al₂O₃ glasses were prepared by the technique of oxide high-temperature melting, the SEM shows that the particle size of Ag NPs is 50-100 nm, Photoluminescence Spectrum of the glasses also match the character emission peaks and characte excitation peaks of Eu3+ ion, When the excitation wavelength is 466 nm, it has an obvious fluorescence enhancement effect, becacuse of the Surface Plasmon Resonance of Ag NPs.