Siloxane-Based Nanocomposites Containing 6LiF Nanocrystals for Thermal Neutrons Detection

In this work, first results on newly developed thermal neutrons scintillators are reported. The main focus is the synthesis and characterization of 6LiF nanoparticles, to be added to the polysiloxane matrix as neutron absorber. The preparation of 6LiF nanocrystals has been pursued by co-precipitation technique, using a mixture of water and ethanol in different ratios. The as-prepared nanocrystals have been characterized in terms of crystal structure and crystallite size by X-ray diffraction, whereas the composition has been investigated by energy dispersive spectroscopy. In this preliminary step towards the realization of a new detector, the commercial inorganic phosphor ZnS:Ag (EJ-600) has been used as scintillating medium. A fixed weight ratio of 6LiF nanocrystals and EJ-600 phosphor has been chosen, namely 3:1 EJ-600:6LiF, whereas different amounts of the mixture have been added to the polysiloxane binder, prior to cross-linking. The composites have been benchmarked as for light output and thermal neutrons detection efficiency against a commercial sample of EJ-426 taken as a reference.