Luminescent properties of BaO-La₂O₃-B₂O₃ glasses with dopant

Abstract

The luminescent properties of glasses synthesized in air atmosphere by conventional high temperature process were studied. The emissions spectra of Eu²⁺ and Eu³⁺ were observed in BaO-La₂O₃-B₂O₃-Eu₂O₃ glasses. The results show that the broad emission peaks at 430 nm correspond to 5d→4f emission transition of Eu²⁺, the sharp emission peaks at 592, 616, 650 and 750 nm correspond to ⁵D₀→⁷F_j(j=1–4) emission transition of Eu³⁺, respectively, which indicates that the BaO-La₂O₃-B₂O₃-Eu₂O₃ glass can convert ultraviolet and green components of sunlight into blue and red light so as to increase the intensity of blue and red light, respectively. The luminescent intensity of Eu²⁺ increases with increasing the molar ratio of Tb³⁺ in BaO-La₂O₃-B₂O₃-Eu₂O₃-Tb₄O₇ glasses, whereas the luminescent intensity of Eu³⁺ decreases. So the luminescent intensity of Eu(III, II) is influenced by Tb³⁺. These phenomena can be explained by electron transfer mechanism: Eu³⁺ (4f⁶) + Tb³⁺ (4f⁸) → Eu²⁺ (4f⁷) + Tb⁴⁺ (4f⁷). Taking advantage of the luminescent properties of BaO-La₂O₃-B₂O₃-Eu₂O₃ glasses, light-conversion glass for agriculture can be produced.

Keywords

luminescent property / rare earth activated glass / light-conversion / BaO / La₂O₃ / B₂O₃ / Eu₂O₃