Thermally stable deep-red emitting Sr2GdTaO6:Mn4+ double perovskites for indoor plant growth LEDs

Indoor artificial cultivation of plants is a novel technology applied to agriculture, and the emission band of luminescent materials can be matched with the needs of plants to promote plant growth. In this contribution, novel Mn4+ doped Sr2GdTaO6 (SGTO) deep-red phosphor was synthesized. This material was characterized, in detail, by X-ray diffractometer, SEM, and photoluminescence emission spectra. Sr2GdTaO6:Mn4+ (SGTO:Mn4+) can be effectively excited by near-ultraviolet (NUV) light, and the broadband emission of deep-red light matches the absorption band of plant phytochromes PR and PFR. The optimum doping concentration of Mn4+ in SGTO was 0.6 mol%, and the concentration quenching mechanism was attributed to dipole-quadrupole (d-q) electric interaction. The photoluminescence emission intensity of SGTO:0.006Mn4+ at 423 K is 80.6% of that at room temperature and the internal quantum efficiency of SGTO:0.006Mn4+ is 36.09%. Finally, the performance of the commercial 440 nm light-emitting diode chip/SGTO:0.006Mn4+ encapsulated light-emitting diode device was stable and can meet the needs of plants for the blue and red light. The results showed that SGTO:0.006Mn4+ deep-red phosphor is expected to be a phosphor suitable for indoor plant growth lighting. (c) 2021 Elsevier Ltd. All rights reserved.

Automated summary

In this study, a novel deep-red phosphor SGTO:Mn4+ was synthesized, which can be effectively excited by near-ultraviolet light and emit deep-red light that matches the absorption band of plant phytochromes. The results indicate that SGTO:0.006Mn4+ is a suitable phosphor for indoor plant growth lighting.