Efficient lifetime-based optical thermometry using BaLaZnSbO6:Mn4+red-emitting phosphors

In this study, a series of Mn-doped BaLaZnSbO6 (BLZSO:Mn4+) phosphors were synthesized by solid-state re-action method. Under 355 nm excitation, the BLZSO:Mn4+ phosphors exhibited a red emission with the peak centered at 697 nm, which was attributed to the 2Eg & RARR; 4A2g characteristic transition of Mn4+ ions. The optimal doping concentration of Mn4+ was found to be 0.6% and the concentration quenching mechanism was attributed to dipole-dipole interaction. Moreover, the structural information, crystal field strength, color purity and thermal stability were studied in detail. Additionally, the temperature-dependent lifetime of Mn4+ ions was monitored in the temperature range of 13-473 K and the maximum Sr value was obtained to be as high as 1.87 K-1. This work reveals that the BLZSO:Mn4+ phosphors have potential in the field of optical thermometer.