The Potential of Silica-Carbon Nanotubes Composite for Electromagnetic Absorber Coating

The utilization of shielding materials to absorb electromagnetic waves has been widely implemented, especially in military technology and equipment. In this study, we developed a composite material based on silicon dioxide ($\mathbf{S i O}_{2}$) and multi-walled carbon nanotubes (MWCNTs) to enhance the electromagnetic wave absorption compared to single material $\mathbf{S i O}_{2}$. In addition, a marine coating matrix was used in this research. The material characterization was done using scanning electron microscope (SEM) analysis to observe the surface morphology. Meanwhile, a vector network analyzer was used to determine scattering parameters at a frequency range of $4-8 \mathrm{GHz}$ and $8-12 \mathrm{GHz}$. The measurement results showed that the absorber layer of $\mathbf{S i O}_{2} /$ MWCNTs $\mathbf{2 w t} \%$ composite had the highest absorption coefficient of 34.37% at a frequency of 7.66 GHz.