The coating of composite nanoparticles of BaFe12O19/multi-walled carbon nanotubes using silicon matrix on nonwoven substrate for radar absorption in X and Ku bands

A novel radar absorbing material was developed on nonwoven fabric using BaFe12O19/multi-walled carbon nanotube, which was synthesized by combustive sol–gel technique. The functional carboxylated multi-walled carbon nanotube was utilized in silicon matrix and printed on fabric surface to enhance the intensity and band width of wave absorption. The crystalline structure, morphology, and magnetic properties were characterized by X-ray diffraction, field emission scanning electron microscope, and vibrating sample magnetometer. The maximum reflection loss of nanoparticles was measured about −7 dB on 9.5 GHz. Moreover, the maximum absorption in X band was close to −38.45 dB in 10.5 GHz at the thickness of 1.5 mm with bandwidth of 2.6 GHz. Moreover, in Ku band, the maximum absorption for BaFe12O19/multi-walled carbon nanotube sample with thickness of 1.5 mm was reported as −31.38 dB, which was recorded on 15.9 GHz with 3.2 GHz bandwidth. Interestingly, the fabric coated with bare BaFe12O19 nanoparticle exhibits a maximum absorption of −3.5 dB at 9.7 GHz, which is lower compared to the absorption value of −17.8 dB at 9.8 GHZ for the fabric coated with BaFe12O19/multi-walled carbon nanotube. However, in Ku band, the fabric coated with BaFe12O19 nanoparticles shows lower value of −2.4 dB compared to X band in 17.6 GHz. In comparison, for composite nanoparticles coated sample, a nearly similar maximum value of −17.6 dB was recorded on 16.7 GHz with band width of 2.2 GHz. Results indicate appreciable maximum absorption value of more than 90% in X and Ku band, which can be attributed to presence of carbon structure in composite material.