Development of Cobalt coated MWCNTs/Polyurethane composite for microwave absorption

This research work describes the design and method of development of microwave absorber and was conducted for analysis of reflection loss performance with the magnetic modifications of Multi-Walled Carbon Nanotubes (MWCNTs). Cobalt coated Multi-Walled Carbon Nanotubes composites were prepared by three step methods. Composites were developed with varying weight percentage of Cobalt (II) Chloride Hexahydrate and Multi-Walled Carbon Nanotubes. The morphology, elementary analysis and absorbing properties of Cobalt coated Multi-Walled Carbon Nanotubes composites were studied by FESEM, EDX and Vector Network Analyzer. The obtained Co coated MWCNTs/PU composite demonstrated the maximum reflection loss of -21.06 dB at 12.63 GHz and the maximum absorption bandwidth of 3.7 GHz, in the frequency range of 8-13 GHz with 3 mm thickness. These microwave absorption parameters can be credited to synergistic effect of improved matched impedance and greater microwave attenuation properties of the absorber. The combined usage of dielectric loss and magnetic loss absorber design shows great diversity and can be a promising candidate for designing high performance microwave absorbing materials.