# Electromagnetic Radiation Shielding Using Carbon Nanotube and Nanoparticle Composites
## 3 CNT-Based Materials for X-Ray and Gamma Ray Attenuation  
CNTs are cylindrical nanoscale tubes with carbon atoms arranged in a hexagonal lattice. CNTs in a powdered form are added to polymers to increase their radiation shielding. However, individual CNTs can also be assembled using different methods to form fabric. CNT-based fabrics have gained significant attention for their potential use in lightweight flexible radiation-protection materials due to their high toughness-to-weight ratio, good electrical and thermal conductivity, low density, and, depending upon the composition and additives, their ability to attenuate radiation through mechanisms such as electrical conductivity, photoelectric absorption, and Compton scattering [49]. The lightweight carbon composition of CNTs provides moderate specific shielding effectiveness against ionizing radiation, including X-rays and gamma rays, making them valuable for the development of efficient shielding and attenuating materials [49]. The addition of boron or cadmium to CNT fabric is especially effective for neutrons. The alignment and resin impregnation of CNT-based fabrics can enhance shielding properties [50]. Studies conducted by [PERSON] et al. [50], [PERSON] et al. [51], and [PERSON] et al. [52] provide a comprehensive summary of the advancements in using CNT-based materials for gamma-ray shielding. Their collective work underscores the significant potential of CNT films in developing efficient and lightweight radiation-shielding solutions. [PERSON] et al. [50] evaluated the effectiveness of CNT films against radiation emissions from Americium-241 (\({}^{241}\)Am) and Caesium-137 (\({}^{137}\)Cs) by assessing the mass attenuation coefficients of CNT film samples. Their systematic experimental characterization and comparative analysis with other materials provided valuable insights into the potential of CNTs for gamma-ray shielding. The findings from [PERSON] et al. demonstrated that CNT films could outperform certain common metals, such as aluminum, for gamma-ray shielding under specific conditions. Their research also suggested that the alignment and resin impregnation of CNT films could further enhance shielding performance. Comparisons with carbon fiber-reinforced composites and metals highlighted the potential of CNT films combined with nanoparticles for lightweight and efficient gamma-ray shielding, pointing out the importance of structural optimization to maximize this potential. The studies advocate for further research into structural optimization and enhancement techniques to fully realize their benefits. [PERSON] et al. [51] investigated the shielding properties of CNT films exposed to gamma-ray irradiation from a Cobalt-60 (\({}^{60}\)Co) source in both air and vacuum environments. Their research focused on isolating and studying the effects of gamma-ray irradiation on individual components of CNT field-effect transistors (FETs) using controlled experimental methods. The study highlighted the relative vulnerability of the SiO\({}_{2}\) substrate compared to the CNT film and the gate oxide layer. Their findings indicate that CNT films not only possess radiation-hardened properties but also shield the underlying SiO\({}_{2}\) substrate from radiation exposure. This research sheds light on the differential effects of radiation on various components of CNT-based electronics, emphasizing the protective capabilities of CNT films in radiation-rich environments. [PERSON] et al. [52] investigated the potential of natural rubber latex (NRL) reinforced with multi-walled carbon nanotubes (MWCNTs) for attenuating gamma rays emitted from Cobalt-60 sources. Employing a comprehensive approach, they used various characterization techniques, including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and gamma radiation shielding tests, to evaluate the properties of MWCNT-reinforced NRL nanocomposites.