γ-ray shielding and mechanical properties of NR/Bi2WO6 composites enhanced by interlayer bonds

Abstract

BackgroundRubber-based nanocomposites have become a research focus in the nuclear industry due to their wide application in wearable radiation protection devices.PurposeThis study aims to explore the γ-ray shielding mechanism of composite material of Bi2WO6 nanoparticles and natural rubber (NR), so as to provide theoretical support for the further materials preparation of low toxicity, light weight and high efficiency radiation shielding.MethodsBismuth tungstate (Bi2WO6) nanoparticles synthesized via hydrothermal process, additionally, WO3 and Bi2O3 particles were prepared by ball milling method. Then, these particles were filled into natural rubber (NR) at the mass fraction of 30% to fabricate three composites: NR/Bi2WO6, NR/WO3 and NR/Bi2O3. Finally, laser particle size analyzer, X-ray diffraction analysis (XRD) and field emission scanning electron microscope (FE-SEM), etc., were employed to access the mechanical properties of NR/Bi2WO6, and the γ-ray shielding effect was evaluated on the basis of the γ-ray shielding effects of Bi2WO6, WO3 and Bi2O3.ResultsThe results show that the NR/Bi2WO6 nanocomposites achieves a γ-ray shielding factor of 13.6% for 59.5 keV (241Am point source), which is significantly higher than NR/WO3 (7.4%) and NR/Bi2O3 (9.2%). Furthermore, a comparison of WO3 and Bi2O3 indicates that the interlayer effect of the Bi2O22+ and WO42- layers in the Bi2WO6 cell is conducive to increasing the probability of collisions between γ photons and extranuclear electrons.ConclusionsThe γ-ray shielding performance of NR/Bi2WO6 composites is significantly improved by the boundary complementary effect of both K and L layer absorption edges of W and Bi elements existed in Bi2WO6 nanoparticles, which enhances the attenuation efficiency of NR/Bi2WO6 to the γ-ray.

Keywords

• γ-ray shielding
• bi2wo6
• composite
• photoelectric effect
• boundary complementary effect
• interlayer bond