NaI:Tl,6Li-PVT composite scintillator toward neutron and gamma discrimination

Efficient and affordable scintillators with the capability of neutron (n) and gamma (γ)-ray discrimination have become increasingly urgent for homeland security and radiation protection applications. In this work, a composite scintillator prototype made of NaI:Tl,6Li (NTL) single crystals and poly(vinyltoluene) (PVT) plastic scintillators was synthesized toward n and γ rays discrimination. The composite scintillator, with a size of 53 mm diameter × 30 mm height, is comprised of four 12 mm × 12 mm × 20 mm rectangular cuboid NTL crystals encapsulated in a PVT-based plastic scintillator matrix. PVT enable the scalability of scintillator to large geometries, and it also serves as light guide and wavelength shifter for NTL scintillation. The synthesized NTL-PVT composite has a high scintillation yield of 36,600 ± 4000 photons/MeV (equivalent to stand-alone NTL crystals), and a decent n and γ-ray pulse shape discrimination (PSD) capability with a figure-of-merit (FOM) of 1.2. These results highlight the feasibility of NTL-PVT composites as cost-effective scintillators with sufficient n and γ-ray detection performance. •The NaI:Tl,6Li-PVT composite has a high scintillation yield of 36,600 ± 4000 photons/MeV.•The NaI:Tl,6Li-PVT composite has a decent n-γ pulse shape discrimination capability with a figure-of-merit of 1.2.•This work highlight the feasibility of NaI:Tl,6Li-PVT composites as cost-effective neutron-gamma scintillators.