Dual-Response Photoluminescence of Rare Earth-Based Halide Double Perovskite

Sb3+-doped rare-earth halide double perovskites (REDPs) have emerged as a novel class of optical and optoelectronic materials for diverse applications because of the enhanced optical properties induced by Sb3+ doping. However, the responsive luminescence features of Sb3+-doped REDPs, especially dual and multi-responsive luminescence, are rarely discovered. Herein, we show that Sb3+-doped Cs2NaScCl6 with blue and yellow-green emission centers exhibits both the excitation wavelength and temperature-responsive luminescence. Specifically, the dual emission centers of Sb3+-doped Cs2NaScCl6 exhibit reverse responses to temperature, changing the emission color of Sb3+-doped Cs2NaScCl6 as the temperature increases from 77 to 440 K. Our studies show that the observed dual-response luminescence should be attributed to the Sb3+ doping-enhanced responsive luminescence of pristine Cs2NaScCl6. The dual-response luminescence enables facile luminescence tuning of Sb3+-doped Cs2NaScCl6 with the assistance of co-doping with Tb3+ and Mn2+ and gives Sb3+-doped Cs2NaScCl6 potential for applications including information encryption, anti-counterfeiting, light-emitting diodes, and temperature sensing.