Evaluation of shielding properties of a developed nanocomposite from intercalated attapulgite clay by Cd/Pb oxides nanoparticles

Abstract

The study investigated new nanocomposites' γ-ray and neutron shielding properties based on raw attapulgite, a clay matrix intercalated with different weight percentages of mixed nanometal oxides CdO and PbO. The various percentages were as follows: (100-2x)%Attapulgite + x%CdO + x%PbO, abbreviated as (AT100-2xCdxPbx), where x= 5, 10, 15%. The nanocomposites were characterized using XRD, FTIR, and EDX, confirming their successful preparation. SEM images revealed that the mixed oxide nanoparticles were successfully intercalated into the layers of attapulgite clay, with an average particle size of approximately 31.46 nm. The bulk densities of the prepared nanocomposites were measured to be in the range of 2.0342 to 2.5550 g/cm3. GEANT4 simulations were employed to evaluate the nanocomposites' γ-ray and neutron shielding performance in the photon energy range of 0.015 to 15 MeV. Phys-X code was used for verification. The simulation results showed a maximum difference of approximately 9.5% between GEANT4 and Phys-X predictions. To assess the γ-ray shielding performance, various shielding parameters were calculated at selected photon energies. The µm values ranged from 4.589 to 0.020 cm2.g-1, 6.311 to 0.021 cm2.g-1, 8.350 to 0.022 cm2.g-1 and 10.804 to 0.023 cm2.g-1 for raw attapulgite, AT90Pb5Cd5, AT80Pb10Cd10, AT70Pb15Cd15 across the photon energy range. The AT70Pb15Cd15 nanocomposite exhibited the highest µm, Zeff, Zeq, and the lowest T1/2, T1/10, and MFP values. Notably, it also demonstrated the highest FNRCS (approximately 0.1 cm-1). These findings suggest that clay-based nanocomposites represent a new class of low-cost, locally available advanced materials with potential applications in γ-ray and neutron shielding characteristics.