Review Study of Some Sillen Structure Chloride Phosphor Materials

Silicates and halides have long been recognized as effective luminescent materials, each with distinct advantages and disadvantages. Silicates are stable but require higher synthesis temperatures, while halides are more suitable for applications like optically stimulated luminescence and scintillation due to their lower melting points and the importance of defects and colour centres. However, most halides, except for fluorides, are quite hygroscopic, which can affect their stability in ambient conditions and necessitate protective measures. Sillen structure lattices present a promising alternative, as they can be synthesized at significantly lower temperatures than silicates and are less hygroscopic than their halide counterparts. Despite their potential, research on sillen structure has not been as extensive as that on silicates and halides. This review aims to summarize existing studies on the synthesis, crystal structures, and luminescence of various Sillen structure chloride phases, encouraging further research in this area.