Investigation of 6Li Enriched Particle Dispersion in Fluorescent Electrospun Polymer Nanofibers to be Used as Thermal Neutron Scintillators

Abstract

Electrospun polymer nanofibers are attractive due to their unique volume-to-surface area, chemical, electrical, and optical properties. Department of Homeland security has interest in applications with polymeric scintillation detectors that directly discriminate between neutron and gamma radiations using manufacturing techniques that are inexpensive and which can be effectively implemented to produce large area detectors. Lithium-6 (6Li) isotope has a significant thermal neutron cross-section and produces high energy charged particles upon thermal neutron absorption. In this research, 6Li loaded polymer composite was successfully spun onto a stationary stainless steel target creating a thermal neutron scintillator made of randomly oriented fibers. Fiber mats thus obtained were characterized using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) for morphology, and fluorospectroscopy for optical properties. Additionally, the fiber mats were characterized for polymeric properties including microstructure evaluation and response to thermal neutrons, alpha, beta, and gamma radiation using suitable radiation facilities. Fiber matrix was made out of an aryl vinyl polymer and a wavelength shifting fluor with efficient resonant energy transfer characteristics. The mats produced had scintillation fibers having diameters from 200 nm to 3.2 μm.