Boosting the thermal stability of A2InTaO6:Cr3+(A = Ca, Sr, Ba) NIR emitters via component regulation

Broadband near-infrared (NIR) light-emitting diodes (LED) with excellent efficiency, and thermal stability are vital light sources for NIR spectroscopic techniques. Nevertheless, there are currently some drawbacks to oxide NIR phosphors, including poor thermal stability. This work has successfully synthesized a series of double perovskite A2InTaO6 (A = Ca, Sr, Ba) phosphors by a conventional high-temperature solid-state method. Using component regulation, the NIR emission peaks span from 866 to 928 nm with a full-width at half maximum (FWHM) of 192 nm. The photoluminescence quantum yield (PLQY) is improved by 23.5%. Moreover, upon 495 nm excitation, the fluorescence intensity of Ba2InTaO6: Cr3+ at 373 K maintains 72.4% of the initial value at 298 K. Eventually, the ideal phosphor has been fabricated into an NIR-emitting LED and demonstrated its benefits in the night vision application.