Enhanced ionizing radiation shielding using zinc oxide nanorods thin film doped with bismuth nitrate and polyethylene oxide

Abstract

The increasing demand for lightweight, eco-friendly, and non-toxic radiation shielding materials has driven significant research into alternatives to conventional shielding solutions. This study focuses on the development of zinc oxide nanorods thin films (ZnONRs-TFs) as a potential candidate for X-ray radiation protection. The films, synthesized via the chemical bath deposition (CBD) technique, were designed in single-layer and double-layer configurations combined with bismuth nitrate (BN) and PEO polymer. Their shielding properties were evaluated through both experimental measurements and Monte Carlo simulations across an X-ray photon energy range of 60–120 kVp. The results revealed that at lower energy levels (60–80 kVp), ZnONRs-TFs doped with 1g of BN exhibited superior shielding performance, attributed to the high atomic number (Z = 83), which enhances photon absorption. In addition, thinner films demonstrated higher linear attenuation coefficients (μ) due to improved packing density, filling interstitial spaces and voids within the nanostructure. At higher energy levels (90–120 kVp), a notable reduction in shielding performance was observed for all samples, driven by increased photon penetration and the prevalence of Compton scattering. Monte Carlo simulations showed strong agreement with experimental results at higher kVp levels (less than 2 % deviation), while discrepancies (∼20 %) at lower energies were attributed to experimental uncertainties, including X-ray tube calibration and secondary photon contributions. The ZnONRs-TFs doped with 1g of BN configuration enhanced shielding across all energy ranges, highlighting its potential as a sustainable and lightweight alternative for ionizing radiation protection. This study contributes to advancing thinner, environmentally friendly radiation shielding materials through nanotechnology.