Timing properties of radioluminescence in nanoparticle ZnS:Ag scintillators

As neutron scattering facilities improve, new neutron detectors with high rate capabilities that can cope with increasing flux are required. Most scintillation detectors at neutron scattering facilities employ ZnS:Ag mixed with 6LiF. These scintillation detectors are efficient, cost effective, and have good gamma rejection but are count-rate limited by the afterglow of ZnS:Ag. In this work nanoparticles of ZnS:Ag were synthesised and investigated to determine their potential for development into higher count-rate capability neutron detectors. Nanoparticles were shown to form micron sized agglomerates with redshifted luminescence compared to bulk ZnS:Ag. The luminescence decay to 1% of the maximum amplitude was demonstrated to be approximately 20 times faster than commercial bulk ZnS:Ag. A significant reduction in afterglow was observed in the nanoparticles. These initial results indicate promise for the use of nanoparticle ZnS:Ag scintillators in future high-rate capability neutron detectors.