摘要： Titrating the aqueous solution of equimolar RE(NO3)3 and (NH4)2SO4 with NH4OH to pH~9 at ~4 °C produced an amorphous precursor that yielded phase-pure and well dispersed RE2O2S nanopowder (RE=Gd0.99Tb0.01; GOS:Tb) via a RE2O2SO4 intermediate upon annealing in H2. The powders calcined at the typical temperatures of 700/1200 °C exhibited unimodal size distributions and have the average crystallize sizes of ~17/55 nm, average particle sizes of ~284/420 nm, and specific surface areas of ~14.62/4.53 m2/g (equivalent particle sizes: ~56/180 nm). The 1200 °C product exhibited sharp green luminescence at ~544 nm (FWHM = 2.3 nm; λex = 275 nm), with an absolute quantum yield of ~24.8% and a fluorescence lifetime of ~1.34 ms at room temperature. It was also shown that the powder possesses favorable thermal stability (the activation energy for thermal quenching of luminescence ~0.305 eV) and is stable under electron beam irradiation up to 7 kV and 50 μA. The synthetic technique has the advantages of scalability and favorable dispersion and high chemical/phase purity for GOS powder, which may allow the sintering of scintillation ceramics at lower temperatures.