Crystalline structure dependence of luminescent properties of Eu³⁺-activated Y₂O₃-Al₂O₃ system phosphors

Eu³⁺ doped Y₃Al₅O₁₂ (YAG), YAlO₃ (YAP) and Y₄Al₂O₉ (YAM) nanophosphors were prepared by solvothermal reaction method. The structural properties were studied by using their XRD measurements and the luminescent properties of these phosphors were investigated by the measurement of their excitation and emission spectra along with their decay curves. The relationship between the structures and the photoluminescence properties of the phosphors has been studied. The emission spectrum of Eu³⁺ doped YAG phosphor is dominated by orange emission due to ⁵D₀ → ⁷F₁ transition with inversion symmetry. However, the emission spectrum of Eu³⁺ doped YAP phosphor is dominated by red emission due to ⁵D₀ → ⁷F₂ transition without inversion symmetry. The PL spectrum of Eu³⁺ doped YAM phosphor consists of similar emission intensities for both ⁵D₀ → ⁷F₁ (590 nm) and ⁵D₀ → ⁷F₂ (607 nm) transitions.