Investigation of luminescent properties of Eu3+ doped double perovskite Ba2ZnMoO6 phosphors by using solid-state reaction method

A series of double perovskite Ba_2−2xEu_2xZnMoO₆ (where x = 0.02–0.12) phosphors with orange-reddish emitting light were successfully synthesized by solid-state reaction method at the synthesizing temperatures of 1000, 1050, and 1100 °C. The X-ray diffraction (XRD) patterns indicated that the crystalline phases of all synthesized Ba_2−2xEu_2xZnMoO₆ powders had the double perovskite structure with the lattice of a = b = c = 0.8264 nm. As fluorescence spectrophotometer was used to measure photoluminescence (PL) properties of the Ba_2−2xEu_2xZnMoO₆ phosphors, 3D scanning method was used to find the optimum excitation wavelength and it was 360 nm. PL emission spectra showed that the emitting light with the sharp peak in one strong band of 597 nm and the broadened peaks in two weak bands of 619 and 630 nm were observed for all the Ba_2−2xEu_2xZnMoO₆ powders even different synthesizing temperatures were used. We had found that the strong emission peak of 597 nm was corresponding to ⁵D₀–⁷F₁ (597 nm) transition of Eu³⁺ ions and two weak emission peaks of 619 and 630 nm were corresponding to ⁵D₀–⁷F₂ (619 nm) and ⁵D₀–⁷F₂ (630 nm) transitions of Eu³⁺ ions. The results of XRD patterns and emission spectra suggest that the optimal synthesizing temperatures of the Ba_2−2xEu_2xZnMoO₆ phosphors are 1100 °C. As 1100 °C is used as the synthesizing temperature, the relationship between the lifetime and the concentration of Eu³⁺ ions in the Ba_2−2xEu_2xZnMoO₆ phosphors can be obtained by the equation: t = − 4.9 × u + 2.1894, where t and u represent an emitting lifetime of the Ba_2−2xEu_2xZnMoO₆ phosphors and the concentration of Eu³⁺ ions.