Synthesis and photoluminescence of Pr3+ doped Gd2O2S scintillation ceramic powders

Gadolinium oxysulfide powders doped with different concentrations of Pr3+ were synthesized using a hydrogen reduction method from Gd2O3, Pr6O11 and H2SO4 starting materials. The synthesized powders were characterized by means of DTA-TG-DTG, FT-IR, XRD, SEM and PL spectrum analysis. The 2Gd2O3·(Gd1-x, Prx)2 (SO4)3·12H2O precursor was synthesized by mixing Gd2O3 and Pr6O11 with dilute H2SO4 at 100°C. (Gd1-x, Prx)2O2SO4 powders was obtained by calcining the precursor powders at 750°C for 2h in air. Single phase gadolinium oxysulfide was prepared by reducing the (Gd1-x, Prx)2O2SO4 powders at 750°C for 1h in flowing hydrogen. The (Gd1-x, Prx)2O2S powders show porous microstructures. Under 307 nm UV light excitation, the (Gd1-x, Prx)2O2S powders show green emission at 511 nm, which corresponds to the 3P0-3H4 transition of Pr3+ ion. The emission intensity is dependent on Pr3+ concentration, and the (Gd0.99, Pr0.01)2O2S powder shows the highest luminescence.