Optical band gaps and spectroscopy properties of Bi m+/Eu n+/Yb3+ co-doped (m = 0, 2, 3; and n = 2, 3) zinc calcium silicate glasses

In this study, the indirect/direct optical band gaps and spectroscopy properties of Bi ^m+/Eu ⁿ⁺/Yb³⁺ co-doped (m = 0, 2, 3; and n = 2, 3) zinc calcium silicate glasses under different excitation wavelengths were investigated. Zinc calcium silicate glasses with the main compositions of SiO₂-ZnO-CaF₂-LaF₃-TiO₂ were prepared by the conventional melting method. EDS analysis was performed to determine the elemental composition existing in the zinc calcium silicate glasses. Visible (VIS)-, upconversion (UC)-, and near-infrared (NIR)-emission spectra of Bi ^m+/Eu ⁿ⁺/Yb³⁺ co-doped glasses were also investigated. Indirect optical band gaps and direct optical band gaps of Bi ^m+-, Eu ⁿ⁺- single-doped, and Bi ^m+-Eu ⁿ⁺ co-doped SiO₂-ZnO-CaF₂-LaF₃-TiO₂-Bi₂O₃-EuF₃-YbF₃ zinc calcium silicate glasses were calculated and analyzed. CIE 1931(x, y) color coordinates for VIS and UC emission spectra of Bi ^m+/Eu ⁿ⁺/Yb³⁺ co-doped glasses were determined. Besides, the mechanism of VIS-, UC-, NIR-emissions, and energy transfer (ET) processes between Bi ^m+ and Eu ⁿ⁺ ions were also proposed and discussed.

Regulated morphology/phase structure and enhanced fluorescence in YF3:Eu3+,Bi3+via a facile method

Using a facile method to regulate morphology/phase structure and significantly enhance the fluorescence in YF₃:Eu³⁺,Bi³⁺.