This study aims to investigate the effectiveness of iron oxide (Fe2O3) and carbon black in micro and nanoscales incorporated into an epoxy adhesive matrix for gamma-ray attenuation. The composites were prepared via a simple and cost-effective synthesis method. The grain size of powder NPs was measured using a transmission electron microscope (TEM), and the particle size was about 20 ± 5 nm and 31.46 ± 2 nm for carbon and Fe2O3, respectively. The morphological properties were characterized by a scanning electron microscope, which indicated the excellent dispersion of NPs, which blocked almost all pores of the composite and increased the capability of radiation attenuation. In addition, the chemical composition of samples using energy dispersive X-rays (EDX) and the compressive strength were measured. Furthermore, the linear and mass attenuation coefficients were determined experimentally for incident photon energies of 59.51-1408.01 keV emitted from γ-ray sources using the sodium iodide scintillation detector NaI. A comparison was conducted between the experimental data and theoretical results that obtained from XCOM software, examined the validity of the experimental results. The relation deviation rate was found to vary between 0.0008 and 2.83%. Furthermore, the measurement of the relation deviation rate between the linear attenuation coefficients of micro and nano composites revealed a range of values between 1 and 25%. Also, shielding parameters such as half-value layer (HVL), tenth-value layer (TVL), mean free path (MFP), and effective atomic number (Zeff) were measured. Moreover, the equivalent atomic number (Zeq), absorption, and exposure buildup factors for prepared samples were calculated. The results showed that the incorporation of Fe2O3 NPs enhanced the shielding capability of the composites, as evidenced by the significant reduction in gamma-ray transmission. The composite materials exhibited excellent mechanical strength, making them suitable for practical applications in radiation shielding. Furthermore, it was determined that the elevation in N-Fe2O3 concentration resulted in a direct increase in the linear attenuation coefficient, from 0.314 to 0.519 cm-1 at 0.5951 MeV and from 0.099 to 0.124 cm-1 at 0.662 MeV. Nevertheless, a slight increase was discerned in the identified mass attenuation coefficients at 0.1332 and 0.1408 MeV. The experimental data for MFP, HVL, and TVL demonstrate that the EFeC4 sample exhibits optimal performance, with values of 1.9, 1.3, and 4.4 cm at 0.5951 MeV, and at 0.661 MeV, the values are 8.04, 5.57, and 18.52 cm, while at 0.1408 MeV, the values are 12.06, 8.36, and 27.78 cm, respectively. Overall, this research highlights the potential of iron oxide-carbon/epoxy composites as efficient and reliable materials for gamma-ray protection in various fields, including nuclear power plants, medical facilities, and space exploration.
Keywords: Epoxy adhesive; N-Fe2O3; Nano carbon; Radiation protection.
© 2024. The Author(s).