Realizing multicolor tunable photoluminescence in La2MgTiO6: Tb3+, Eu3+ phosphors via energy transfer and application for white light-emitting diodes.

The achievement of multiple emission color phosphors has a significant importance in screen display, lighting devices, and multicolor imaging, but it still faces formidable challenges. In this work, double perovskite La 2 MgTiO 6 : Tb3+, Eu3+ phosphors with tunable emissions are designed and successfully synthesized. The obtained phosphors can emit intense green (Tb3+), red (Eu3+), and yellow emissions (Tb3+/Eu3+) via varying the co-doping concentration of Tb3+ and Eu3+. The CIE coordinates exhibit an excellent linear behavior in La 2 MgTiO 6 : Tb3+, Eu3+, revealing the possibility of linear adjustment of multiple emission colors. Detailed material characterization demonstrates that the multicolor tunable emission originates from energy transfer between Tb3+ and Eu3+. The decay dynamics analysis suggests that the multipole interaction between Tb3+ and Eu3+ is quadrupole-quadrupole interaction. A white light-emitting diode device with color rendering index of 84.7, correlated color temperature of 4684 K, and CIE coordinate of (0.3472, 0.3083) is fabricated by combining La 2 MgTiO 6 : Tb3+, Eu3+ yellow phosphor and BaMgAl 10 O 17 : Eu2+ blue phosphor. Our results reveal that La 2 MgTiO 6 : Tb3+, Eu3+ phosphors are promising luminescent materials in white light-emitting diodes. [Display omitted] • The linear adjustment of tunable luminescence from green to yellow and red region under excitation at 377 nm is achieved. • The influence of Tb3+/Eu3+ single- and co-doping concentration on luminescence performance is studied. • The yellow-emitting La 1.695 MgTiO 6 : 0.3 Tb3+, 0.005 Eu3+ phosphor have promising application in WLED. [ABSTRACT FROM AUTHOR]