Broadband electromagnetic shielding and dielectric properties of polyaniline-stannous oxide composites

Conducting polyaniline-stannous oxide (PAni-SnO) composites were synthesized by the in situ polymerization of aniline in the presence of SnO. The composites formed were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). As there is a greater need for materials with electromagnetic interference (EMI) shielding properties over a large operating frequency band, the present study highlights the dielectric and EMI shielding response of PAni-SnO composites in the microwave frequency range from 8 to 18 GHz (X and Ku bands). All the computations were based on microwave scattering parameters measured by transmission line waveguide technique. The EMI shielding effectiveness (EMI SE), return loss, microwave absorption and dielectric properties of the PAni-SnO composites were evaluated for various wt% of SnO (10, 20, 30, 40 and 50 wt%) in PAni. In X-band, the composites exhibits EMI SE in the range - 18 to - 23 dB, with microwave absorbance of 70-83 % and in the Ku-band, the composites exhibits EMI SE values of - 17.5 to - 22.5 dB with 67-85 % absorbance. Our investigations reveal that the PAni-SnO composites are potential candidates for EMI shielding applications for both the X and Ku bands.