[en] Persistent luminescence (PeL) was obtained from glasses with the composition (75NaPO₃-25CaF₂) (in mol%) by adding PeL microparticles SrAl₂O₄:Eu²⁺,Dy³⁺ in the melts using the direct doping method. The glasses exhibit a strong PeL although they crystallize upon quenching. The crystallization was related to the poor thermal stability of the glass, and also to the extensive loss of fluorine during the glass preparation. The use of quartz crucibles and the long process time used to prepare glasses using the direct doping method are responsible for the fluorine losses.

[en] Strong persistent luminescence (PeL) from silica bodies was obtained, for the first time, by sintering silica powder mixed with PeL SrAl₂O₄:Eu²⁺,Dy³⁺ microparticles (MPs). We show that it is not possible to prepare transparent PeL silica glass due to the decomposition of the MPs, which occurs already at 1450 °C. The MPs decomposition was associated with the precipitation of Sr₃Al₁₀SiO₂₀ phase when sintering up to 1650 °C and of SrAl₂Si₂O₈ when sintering between 1650 and 1750 °C. Cristobalite was found to also precipitate when sintering for 10 min but has no impact on the PeL of the bodies.