Barium ferrite nanoparticles: a highly effective EMI shielding material

Electromagnetic interference (EMI) is one of the main causes for the failure of electronic devices working in close vicinity of EM field induced by the neighboring electronic device. Therefore, we report a facile synthesis of barium ferrite (BaFe12O19) nanoparticles via sol-gel technique for efficient EMI shielding application. These nanoparticles were annealed at 400 degrees C, 700 degrees C, and 850 degrees C to investigate the effect of temperature on shielding efficiency and morphology of BaFe12O19 nanoparticles. The structure, morphology, phase purity, magnetism, and shielding effectiveness were analyzed using Fourier-transform infrared (FT-IR) spectroscopy, x-ray diffraction (XRD), electron microscopy (SEM and TEM), vibrating sample magnetometer (VSM) and vector network analyzer, respectively. These studies suggest that BaFe12O19 nanoparticles annealed at 850 degrees C exhibit crystalline pure phase hexagonal structure with the high magnetic moment (31.32 emu g(-1)) and coercivity (2.7 kOe). The total shielding effectiveness of the same was found to be -17.57 dB at 11.58 GHz, which is much higher than those of earlier reported studies.