Photoluminescence behavior of Eu³⁺ doped XAl₂O₄(X = Mg, Ca, Sr and Ba) phosphors: a comparative study

In this work, the Eu³⁺doped stuffed tridymite type structure of alkaline earths aluminate i.e. XAl₂O₄(X = Mg, Ca, Sr and Ba) phosphor materials have been synthesized by conventional high temperature solid state reaction method at 1623 K. The Samples were structurally and morphologically characterized by x-ray diffraction (XRD) and Scanning electron microscope (SEM) measurements. The vibrational behavior of the phosphor samples were investigated by Fourier transform infrared (FTIR) measurements. The phosphor samples emit intense red emission in 610-615 nm range due to⁵D₀ → ⁷F₂transition of Eu³⁺ion on excitation with charge transfer band (CTB) wavelength arising due to Eu³⁺-O^2-and also by the discrete bands of Eu³⁺ions .The decay time of⁵D₀level of Eu³⁺ion were recorded on excitation with 393 nm and by the CTB wavelength for all the four samples. The optimized 1 mol% Eu³⁺doped CaAl₂O₄phosphor exhibits optimum emission intensity and color purity under the excitation with 393 nm than others. The decay time is also found to be larger in the case of Eu³⁺doped CaAl₂O₄phosphor sample. Therefore, Eu³⁺doped CaAl₂O₄phosphor may be promising material for red color light emitting applications and white light generation.