Ceramics-Silikáty 55, (3) 251 - 255 (2011)

Red-emitting phosphors Ba_2-xMgSi₂O₇: Eu_x³⁺ was prepared by combustion-assisted synthesis method and an efficient red emission under near-ultraviolet (UV) was observed. The luminescence and crystallinity were investigated using luminescence spectrometry and X-ray diffractometer. The emission spectrum shows that the most intense peak is located at 614 nm, which corresponds to the ⁵D₀ → ⁷F₂ transitions of Eu³⁺. The phosphor has two main excitation peaks located at 394 and 465 nm, which match the emission of UV and blue light-emitting diodes, respectively. The effect of Eu³⁺ concentration on the emission spectrum of Ba₂MgSi₂O₇:Eu³⁺ phosphor was studied. The results showed that the emission intensity increased with increasing Eu³⁺ concentration, and then decreased because of concentration quenching. The critical quenching concentration of Eu³⁺ in Ba₂MgSi₂O₇: Eu³⁺ phosphor is about 0.05 mol. The mechanism of concentration quenching of Ba₂MgSi₂O₇: Eu³⁺ luminescence is energy transfer between Eu³⁺ ions casued by the dipole-dipole interaction.