Synthesis, structural and luminescent properties of Pr³⁺ activated GdAlO₃ phosphors by solvothermal reaction method

Different concentrations of trivalent praseodymium (Pr³⁺) ions activated GdAlO₃ nanophosphors were synthesized by solvothermal reaction method. Thermogravimetric/differential thermal analysis (TG/DTA) and X-ray diffraction (XRD) measurements were used to investigate the phase transformations that occur during the preparation of these phosphors. The morphology of the powder after heat treatment was observed by scanning electron microscopy (SEM). The luminescent studies on these compounds have been carried out from the measurements of their photoluminescence (PL) and photoluminescence excitation (PLE) spectra. The PL spectra show blue-green emission corresponding to the f-f transitions of Pr³⁺ (³P₀ → ³H₄) and red emission corresponding to the f-f transition of Pr³⁺ (³P₀ → ³H₆) by monitoring the excitation with f-f transition of Pr³⁺ ( ³H₄ → ³P₂) at 449 nm. Emission mechanism in these systems has also been elucidated by an energy level scheme.