Luminescence Investigation of Red Phosphors La3Ga5SnO14:Eu3+ with High Color Purity and Application in w-LEDs.

Abstract

A series of newly synthesized red-emitting phosphors, La₃Ga₅SnO₁₄:Eu³⁺, were produced through high-temperature solid-state synthesis methods. The phase purity, particle morphology and optical properties were systematically investigated in this work. The prepared fluorescent material has high phase purity. La₃Ga₅SnO₁₄:Eu³⁺ has a strong red emission peak at 612 nm at the excitation at 268 nm, which is caused by the radiative transitions of electrons (⁵D₀→⁷F₂). The optimal doping concentration of Eu³⁺ was observed to be 30 mol% in this series of La₃Ga₅SnO₁₄:Eu³⁺. The mechanism of concentration quenching was determined to be dipole-quadrupole interaction. The chromaticity coordinates of La₃Ga₅SnO₁₄:30 mol%Eu³⁺ were (0.648, 0.352) with a corresponding high color purity of 100%. The thermal stability of the phosphor was also characterized. The luminous intensity could be sustained at 54% at 480 K. The quantum efficiency of the La₃Ga₅SnO₁₄:30 mol%Eu³⁺ phosphor is 64.4%. The exhaustive findings from this study form the basis for advocating the application of these phosphors in light-emitting devices.