Structural and photon/neutron attenuation features of PbNi/CNT nanocomposites: An experimental approach

Abstract

In this work, PbNi/CNT nanocomposites were prepared by sodium borohydride method at varying metallic molar ratios for determination of their structural and nuclear radiation shielding properties. As-prepared PbNi/CNTs were characterized by using transmission electron microscopy (TEM), scanning electron microscopy energy-dispersive X-ray spectroscopy (SEM-EDX), elemental mapping, and X-ray diffraction (XRD). Average particle sizes of Pb40Ni60/CNT, Pb60Ni40/CNT, Pb80Ni20/CNT, and Pb20Ni80/CNT materials were obtained as 5.6, 3.8, 4.2, and 4.2 nm, respectively. Radiation attenuation properties of the produced nanocomposites were investigated experimentally by irradiating the samples with gamma photons in the 34–383 keV energy range. The accuracy of the experimental results was checked with outcomes calculated with EpiXS software. Mass attenuation coefficient (MAC) was found in the range of 22.924–0.108 cm2/g, 5.473–0.129 cm2/g, 3.767–0.109 cm2/g, and 4.626–0.128 cm2/g for Pb20Ni80/CNT, Pb80Ni20/CNT, Pb40Ni60/CNT, and Pb60Ni40/CNT samples, respectively. Also, other photon shielding parameters (HVL, Zeff, EABF, and EBF) were calculated to make a comprehensive evaluation. The results show that 30% by weight Pb80Ni20 doped CNT has the lowest HVL and buildup factors values and the largest MAC, Zeff values. Finally, macroscopic cross-section values (ΣR) were obtained to estimate the ability of the nanocomposite samples to reduce the energy of fast neutrons. It was revealed that the ΣR values of the samples were in the range of 0.158–0.169 cm−1 and they had higher ΣR values than conventional neutron moderators.