Optical properties and energy transfer of Tm3+ single-doped and Tm3+-Tb3+ co-doped transparent glass-ceramics containing NaGd(MoO4)2 single phase

Tm³⁺ single-doped and Tm³⁺-Tb³⁺ co-doped SiO₂–B₂O₃–Na₂O–ZnO–MoO₃-Gd₂O₃ glasses were successfully prepared by the melt-quenching process. X-ray diffraction and transmittance measurements were used to determine that the optimal heat treatment regime consisted of crystallization at 620 °C for 5 h and transparent glass-ceramics containing the NaGd(MoO₄)₂ single phase were obtained. The characterization results by SEM confirmed that the size of the crystals precipitated in the glass matrix was on the nanometer level. The effects of different contents of Tm2O3 on the luminescent properties of glass-ceramics in this system were explored. The results showed that the emission peak at 453 nm (¹D₂→³F₄) had the highest intensity when Tm₂O₃ was doped with 0.5 mol% under the wavelength at 359 nm excitation. In addition, with the gradual increase of Tb₂O₃ contents, the luminescence colour of the Tm₂O₃–Tb₂O₃ co-doped glass-ceramics gradually shifted from blue to green. This indicates its potential application in blue-green light display technologies and various other areas. The experimental results of the water resistance stability of the samples show that the co-doped glass-ceramic still has good luminescence stability after being immersed in water, which provides further favourable support for its application.