Influence of co-doped alumina on the microstructure and radioluminescence of SrHfO₃:Ce ceramics

SrHfO3:Ce and SrHfO3:Ce,Al powders were prepared by the solid-state synthesis using the commercial HfO2, SrCO3, CeO2 and alpha-Al2O3 as the starting materials. All the SrHfO3:Ce and SrHfO3:Ce,Al powders calcined at different temperatures within 1100 degrees C-1300 degrees C for 8 h in air exhibited a pure SrHfO3 phase. Meanwhile, the effects of different calcination temperatures and co-doped alumina on the microstructure of SrHfO3:Ce,Al powders were discussed. SrHfO3:Ce and SrHfO3:Ce,Al ceramics were successfully fabricated via the vacuum sintering at 1800 degrees C for 20 h. The alumina acted as the sintering aid, which promoted the densification and eliminated the intragranular pores of SrHfO3:Ce,Al ceramics. The charge disbalance was effectively compensated by co-doped alumina. SrHfO3:Ce,Al ceramics exhibited a higher light yield of 5700 ph/MeV compared with 4600 ph/MeV obtained in SrHfO3:Ce ceramics. The charge traps in ceramics and their effects on scintillation properties were also investigated by thermoluminescence measurement.