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