Photoluminescence and phase related cathodoluminescence dynamics of Pr³⁺ doped in a double phase of ZnTa₂O₆ and ZnAl₂O₄

A new phosphor ZnTaAlO₅:Pr³⁺, which displays cathodoluminescence intensity that is phase dependent, was synthesised by solid state reaction. x-ray diffraction, scanning electron microscopy and EDX (energy dispersive x-ray spectroscopy) maps were used to confirm the multi-phase, multi-particle shapes and to assign each particle shape o a corresponding phase of the phosphor, respectively. Cathodoluminescence maps were obtained simultaneously with the EDX maps, and showed both the luminescence emerging from intrinsic and extrinsic defect centres. The activator red emission was better resolved using photoluminescence spectroscopy, which showed emission lines emerging from more than one manifold of the Pr³⁺ transitions. The persistent luminescence was measured and the corresponding electron trapping centres were characterised by thermoluminescence spectroscopy.