Tunable luminescent properties of BaGd₂ O₄ :Eu³⁺ scintillating phosphors by Pr³⁺ -codoping

BaGd₂ O₄ :Eu³⁺ scintillating phosphors by Pr³⁺ -codoping were synthesized at 1300°C in air using a solid-state reaction method. The as-synthesized phosphors were characterized by X-ray diffraction (XRD), photoluminescence (PL) including excitation and emission spectra, radioluminescence (RL) spectra excited by X-ray and thermoluminescence (TL) spectra. Both the PL and RL spectra are composed of the featured trivalent europium (Eu³⁺ ) without any praseodymium (Pr³⁺ ) ions, and the PL and RL intensities as well as the lifetimes of BaGd₂ O₄ :Eu³⁺ scintillating phosphors decrease dramatically with an increasing concentration of Pr³⁺ ions. Finally, the TL spectra reveal the trap concentration of the existing defects decrease with an increasing concentration of Pr³⁺ ions, while the relative TL intensity ratio of the high temperature band to the low temperature one increases with an increasing concentration of Pr³⁺ ions, which results in the afterglow suppression of BaGd₂ O₄ :Eu³⁺ scintillating phosphors.