Photostimulated and persistent luminescence of samarium ions in BaFCl

Storage phosphors with efficient photostimulated luminescence (PSL) and/or persistent luminescence (PersL) are in great demand for a range of applications. In this paper, PSL, PersL and thermoluminescence (TL) of samarium ions doped in a macroscopic and sub-micron crystals of BaFCl are reported, and it is demonstrated that the co-precipitated BaFCl:Sm³⁺ sub-micron crystals become an efficient photostimulable X-ray storage phosphor upon annealing in the temperature range of 200–500 °C. The dependence of storage phosphor properties on annealing temperature was investigated and it was found that the X-irradiated co-precipitated BaFCl:Sm³⁺ crystallites (~400 nm size) showed maximum PSL and PersL from both Sm²⁺ and Sm³⁺ ions when annealed at 500 °C for 4 h. From a comparison with data for the macroscopic crystal (~3 mm) and ball-milled nanopowders (~30 nm), it also followed that PSL and PersL in the BaFCl:Sm system is affected by the crystal size. TL from Sm²⁺ of the macroscopic crystal is compared with the TL of sub-micron powders annealed at different temperatures.