Photoluminescence and cathodoluminescence properties of CaLaGa₃O₇:Eu³⁺ phosphors

The CaLaGa₃O₇:Eu³⁺ phosphor was prepared by a chemical co-precipitation method. Field emission scanning electron microscopy (FE-SEM), laser particle size analysis, X-ray diffraction (XRD), photoluminescence (PL), and cathodoluminescence (CL) spectra were utilized to characterize the synthesized phosphor. The results revealed that the phosphor was composed of microspheres with a slight agglomerate phenomenon and was spherically shaped. The average grain size was about 1.0 μm. Eu³⁺ ions, as luminescent centers, substituted La³⁺ ions into the single crystal lattice of CaLaGa₃O₇ with the sites of C_s. Although the CL spectrum was greatly different from the PL spectrum, it had the strongest red emission corresponding to the ⁵D₀ →⁷F₂ transition of Eu³⁺. Under the excitation of UV light (287 nm) and electron beams (1.0-7.0 kV), the chromaticity coordinates of the phosphor were found to be in the nearly red and orange light regions, respectively.