Enhanced luminescence properties of double perovskite (Ba, Sr)LaMgSbO6:Eu3+ phosphors based on composition modulation

Eu3+-doped double perovskite (Ba, Sr)LaMgSbO6 phosphors were synthesized by the traditional solid-state reaction method. Structure evolution was investigated by X-ray diffraction and Rietveld structure refinement. The crystallographic data of powders were given in detail. Also, the photoluminescence properties, including excitation spectra, emission spectra, intensity ratios of I (5D0-7F2)/I (5D0-7F1), Commission International de L'Eclairage (CIE) chromaticity coordinates, UV-vis diffuse reflectance spectra, lifetimes, and the thermal quenching properties were thoroughly discussed. With the increase of Sr2+ concentration, the emission intensities increased and the decay times decreased. Band gap was calculated to explain the phenomenon of the increased emission intensity. The phosphors showed temperature-sensitive luminescent properties based on the thermal quenching performance. The configurational coordinate diagram was used to explain the thermal quenching mechanism.