Rare-earth-free Mn4+-doped double perovskite structure phosphor for near ultraviolet excitation of WLED and plant cultivation

●Novel red-emitting Mn4+ doped double perovskite structure phosphors were successfully synthesized for the first time.●The phosphors possess a strong red emission and broad excitation matched well with commercial n-UV chips.●The phosphors show high quantum efficiency and good luminescence thermal stability. Phosphor covered light-emitting diodes (PC-LEDs) are wide applied to diverse fields due to its great advantages compared with the traditional light source. Therefrom, we report new rare-earth-free red-emitting Mn4+ doped Ca2InSbO6 and Sr2InSbO6 phosphors with excellent photoluminescence performance by the solid phase synthesis route. The resultant samples possess broad excitation band that is able to match well with current commercial near-ultraviolet (n-UV) chips and exhibit strong red emission at the excitation of n-UV light. Importantly, the quantum efficiency of the Mn4+-doped Sr2InSbO6 phosphor is measured to be 55.93%. Simultaneously, the quenching temperature of two phosphors is 403 and 438 K. Finally, the LED devices with strong white light are got and provided with low correlated color temperature (CCT) and good color-rendering index (CRI) values. And the emission spectrum overlaps with absorption curve of phytochrome protein Pfr. These results indicate the obtained sample can be a candidate for WLEDs and plant cultivation.