Abstract: A series of Ba₂YAlO₅∶0.2Eu³⁺, xNa⁺(x=0.01, 0.03, 0.05, 0.10, 0.20, 0.30) phosphors were synthesized successfully by high temperature solid phase method. The effect of Eu³⁺, Na⁺ doping on the crystal structure was studied. Observe the morphology of fluorescent materials with scanning electron microscope. The excitation and emission optical properties of phosphors were observed and analyzed by fluorescence spectrometer. Conducted theoretical research on concentration quenching and energy transfer. Under 613 nm emission, O^2-→Eu³⁺ charge transfer band appears at 270 nm to 290 nm, peaks appear at 395 nm and 465 nm, the peak at 465 nm is the highest, corresponding to the ⁷F₀→⁵D₂ transition. Under 465 nm excitation, it is observed that emission peak is the strongest at 613 nm, corresponding to the ⁵D₀→⁷F₂ transition, and the optimal doping concentration of sodium ion is x=0.03. Theoretical calculation verified that the energy transfer in the host material is between the nearest neighbor ions. Thermal stability test analysis of the luminescent material show that activation energy of thermal quenching is 0.058 eV, and color coordinates of Ba₂YAlO₅∶0.2Eu³⁺, 0.03 Na⁺ phosphors are calculated locate in (0.61, 0.39), which is very close to the standard chromaticity coordinates (0.67, 0.33) stipulated by the International Commission on Lighting.

Key words: phosphor, high temperature solid phase, photoluminescence, concentration quenching, energy transfer, thermal stability, chromaticity coordinate