Eco-friendly gamma radiation protection using waste rice straw and animal glue enhanced by micro and nano iron oxide: a Geant4 simulation and experimental study

Abstract The current investigation is directed towards the synthesis of new radiation shielding composites utilizing natural and eco-friendly components, including rice straw and animal glue. The experimental methodology involved preparing samples through the blending of 20% wt. rice straw with 80% wt. animal glue, followed by the addition of micro- and nano-sized powders of iron oxide (Fe 2 O 3 ) at varying concentrations (10%, 18.2%, and 25%). The performance of γ -ray protection of the prepared composites was assessed and analyzed by measuring different shielding parameters such as mass attenuation coefficient (MAC), linear attenuation coefficient ( μ ), mean free path (MFP), half value layer (HVL), tenth value layer (TVL), effective atomic number (Z eff ), equivalent atomic number (Z eq ), and build-up factor (BFs) across various photon energies (0.059 MeV to 1.408 MeV). Experimental results of the MAC were compared with theoretical data from XCOM and simulated data from the Geant4 code, indicating good agreement and validating the experimental findings. The results showed that the addition of nano-Fe 2 O 3 (25 wt%) to the composite sample had the highest μ values, which varied between 0.34260 and 0.05274 cm −1 as γ -ray photon energy increased from 0.0595 to 1.408 MeV, respectively. Furthermore, the highest relative increase rate in μ values between nano and micro composites was 24.11%, achieved for the nano Fe 2 O 3 (25 wt%) composite sample at 0.0595 MeV. In conclusion, the investigation demonstrated improved γ -ray protection with the addition of nano-Fe 2 O 3 compared to bulk counterparts.