Novel persistent phosphors Eu2+ - doped Sr5SiO4Cl6 with codopants Cr3+ and Sc3+ in high temperature application

New cyan long persistent luminescence (LPL) phosphors Sr5SiO4Cl6:Eu2+, Cr3+/Sc3+ (SSC: Eu2+, Cr3+/Sc3+) have been prepared. The LPL behaviors of the SSC are greatly enhanced through incorporating Cr3+ and Sc3+ ions as trap centers. The fluorescence and phosphorescence spectra of SSC:Eu2+, Cr3+/Sc3+ both show an asymmetric wide emission band at 446 nm, which is attributed to the 4f65 d1→4f7 transitions of Eu2+ions in two different Sr2+ sites. The LPL of the SSC:0.03Eu2+, 0.03Cr3+ can remain 11760 s above the identifiable intensity level (0.32 mcd⋅m−2) after 10 min of excitation (for SSC:0.05Eu2+, 0.05Sc3+, 4080s). In addition, the temperature-dependent afterglow decay curves also show good afterglow initial brightness at 443 K for SSC:0.03Eu2+, 0.03Cr3+ (for SSC:0.05Eu2+, 0.05Sc3+, 343 K). This research provides new blue LPL phosphors with potential applications in high temperature environment.