Luminescence characteristics of Y2-x-yBixEuyMgTiO6 phosphors

Abstract

BackgroundDouble perovskites have become a research hotspot in recent years due to their flexible structure, easy doping, and good thermal stability. Photoluminescence (PL) of rare-earth-doped double perovskite materials has been frequently reported, but few studies on thermoluminescence (TL) have been conducted.PurposeThis study aims to investigate the TL characteristics of Y2-x-yBixEuyMgTiO6 (0≤x<1, 0≤y<1) phosphors.MethodBi3+ and Eu3+ co-doped Y2MgTiO6 samples were synthesized by a high-temperature solid phase method, and the X-ray diffraction (XRD), PL, and TL of the samples were measured.ResultsXRD analysis results show that the crystal structures of all samples are monoclinic P21/n, and Bi3+ and Eu3+ are doped into Y2MgTiO6 by substituting Y3+. The PL results show that Y1.79Bi0.01Eu0.20MgTiO6 has a strong red emission near 620 nm (corresponding to the 5D0→7F2 transition of Eu3+), which is accompanied by a long afterglow. The TL curves of the samples doped with different concentrations of Bi and Eu ions show that Y1.79Bi0.01Eu0.20MgTiO6 has the highest TL sensitivity, and the samples exhibits two significant TL peaks near 510 K and 610 K. The TL spectrum is more abundant than the fluorescence spectrum, and the 5D0→7FJ (J =1,2,3,4) transition of Eu3+ can be observed. The TL intensity of the sample has a good linear relationship with the irradiation dose in the range of 2~1 000 Gy. The TL kinetic parameters of the samples are analyzed using two methods under different preheating temperatures (Tm and Tstop) and glow curve deconvolution. The analysis results show that the depth of the TL trap in the sample extends from 0.80 eV to 1.40 eV.ConclusionsThe results of this study indicate that the TL spectrum is richer than the PL spectrum and that Y1.79Bi0.01Eu0.20MgTiO6 may be used as TL dosimeter material for large dose detection.

Keywords

• y2mgtio6
• rare-earth doping
• photoluminescence
• thermoluminescence
• activation energy