The CaSO4:Eu–Ag composite material: Thermo-photoluminescence study

The CaSO₄:Eu powder composites with and without silver nanoparticles (NP) with selected grain size were analysed by thermoluminescence (TL), photoluminescence (PL) and time-resolved spectroscopy. Both Eu²⁺ and Eu³⁺ species are present. The former was identified by the emission around 380 nm and the latter by its typical ⁵D₀–⁷F_J transitions and two sites were identified. The addition of silver as nanoparticles enhances the TL signal (240 °C), which is adequate for dosimetry, and has quenching effect on the PL properties, because the most intense luminescence comes from the sample without silver and the lifetimes of the ionic species are not sensitive to the presence of Ag(NP). - Highlights: • The Ag(NP) system enhances the number of defects and then the TL signal. • The remaining TL signal is at 240 °C, adequate for dosimetry. • The Ag(NP) system suppresses the PL signal of both Eu^2+,3+ species. • The Ag(NP) system has negligible influence on the emitting level lifetimes. • One let the hypothesis that the Ag(NP) system only hides the luminescent ions