Nanosized grain polycrystalline scintillators for special nuclear materials detection

The aim of this work was to explore the limits of polycrystalline ceramic scintillator in countering the nuclear threat. The goal was to develop a polycrystalline LaBr3:Ce, which can be processed from ceramic forming techniques and can be produced in large size scintillator panels with lower cost and high production rate. Three high purity raw powders were used as the starting materials including LaBr3, LaCl3, and CeBr3- Powder characteristics were measured. A melt spinning method was used to synthesize the nanoparticle LaBr3:Ce with stoichiometric compositions. The synthesized nanoparticles were characterized and the average particle size of the synthesized nanoparticle LaBr3:Ce was about 50 nm. The melt spun powders were consolidated using a "Nanosintering" method to achieve a high density while maintaining the stoichiometric composition. The grain size of the sintered polycrystalline is about 50 nm, which shows no grain growth during the densification process.