Microwave absorption properties of substituted BaFe12O19/TiO2 nanocomposite multilayer film

The nanocomposite multilayer film (NCMF) of substituted BaFe12O19 and TiO2 was prepared using sol-gel method. BaFe10.5Al1.5O19, BaFe10.1Al1.9O19 and BaFe11.4Cr0.6O19 with different absorption frequencies were selected to fabricate the multilayer film with TiO2. The morphology, crystalline structure and microwave absorption property of the NCMF were investigated with an atomic force microscopy, X-ray diffraction and vector network analyses. The results show that the NCMF is uniform without microcracks and it is an ideal microwave attenuation material with a broad frequency range. Its maximum loss efficiency is about -40 dB. The frequency range with the loss above -10 dB is more than 7 GHz. The multilayer film assembles the achievements of each layer film. Moreover, the compounding of ferrites with TiO2 is helpful to absorb more microwave energy. TiO2 particles block the growth of ferrite grains and make most of their size within nanometers. TiO2 also improves the dielectric loss efficiency of the NCMF.