Zero-thermal quenching luminescence and sensitization effect of Eu3+ in Ca3LiSbO6:Mn4+ red phosphor

Double perovskite Ca3LiSbO6:x%Mn4+, y%Eu3+ far-red emitting phosphors with zero-thermal quenching properties as well as the sensitization effect of Eu3+ ions were reported. The Ca3LiSbO6:0.4%Mn4+ phosphor showed an emission intensity of 109 % at 423 K compared with that at 298 K. In addition, the emission intensity of Ca3LiSbO6:0.8%Mn4+, 4%Eu3+samples can be enhanced to about 1.25 times that of Ca3LiSbO6:0.4%Mn4+ due to the sensitization of Eu3+ ions. Meanwhile, the Ca3LiSbO6:0.8%Mn4+, 4%Eu3+ phosphor showed an internal quantum efficiency (IQE) of 78.9 % as compared with that of Ca3LiSbO6:0.4%Mn4+ (60.7 %), and the external quantum efficiency (EQE) also enhanced from 52.8 % to 68.5 % at the same time. Under the excitation of 365 nm light, the Ca3LiSbO6:x%Mn4+, y%Eu3+ samples display an emission peak at 698 nm, which is appropriate for the absorption of plant pigments including chlorophyll a, b and phytochrome of PFR. The result indicates that the Ca3LiSbO6:x%Mn4+, y%Eu3+ phosphors may have a potential in the application fields of pc-LEDs and indoor plant cultivations.