A soft-glass matrix composite with preservation of blue persistent luminescence

Abstract

Materials with Persistent Luminescence (PeL) are generally produced as powder and must be embedded in solid materials to enable practical applications, such as overnight signaling. PeL phosphors can be embedded in glass to increase the luminescence intensity; however, the incorporation of the phosphor in the molten glass often results in glass crystallization and/or dissolution of the PeL crystals, which compromises the overall afterglow response. Hence, in this work, a soft-glass matrix composite (SGMC) doped with commercial Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺ (SMSO) was obtained by direct incorporation at liquidus temperature. The process resulted in a homogeneous dispersion of the blue-emitting SMSO particles, as indicated by microtomography analysis. The interaction between the glass and PeL crystal was explored by using Raman and energy-dispersive X-ray elemental mapping, which indicated the absence of significant interaction between the host and particles. The thermoluminescence analysis presented a 20 °C band shift of the main emission, although the afterglow profiles remained unaltered. Therefore, a SGMC was obtained under mild conditions and temperatures, preserving the SMSO particles within the glass matrix and their afterglow performance. The direct incorporation method guided by the complete thermal profile of the soft-glass matrix can improve the incorporation of crystalline materials into molten glasses.