Structural, magnetic and microwave absorption properties of Ce-doped barium hexaferrite

Ba1−xCexFe12O19 (x=0.0, 0.05, 0.1, 0.15, and 0.2) polycrystalline samples were synthesized by the sol-gel method and characterized by thermogravimetric analysis (TG), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), vibrating sample magnetometer (VSM) and vector network analyzer. All the synthesized samples showed nearly single magnetoplumbite phase and an average particle size of the undoped sample of about 500 nm decreasing with Ce doping content. The magnetization first increased and then decreased with the increase in Ce; on the other hand, coercivity showed no regular behavior with Ce content. Maximum values of magnetization (53 emu/g) and coercivity (5088 Oe) were obtained for x=0.1. Microwave absorption measured within the 2-18 microwave frequency range indicated maximum reflection losses of −16.74 dB at 10.3 GHz and of −20.47 dB at 16.22 GHz for x=0.15 and x=0.2 samples, respectively. The present investigation suggests Ce substituted barium hexaferrite as a promising candidate for microwave absorbing materials.