Synthesis and electromagnetic properties of La-doped Ni-Zn ferrites

The La3+ doped spinel ferrites, Ni0.8Zn0.2LaxFe2-xO4,Were prepared by a sol-gel method. The samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), vibrating sample magnetometer (VSM) and vector network analyzer (VNA). Results show that La3+ can completely substitute into the lattice of Ni0.8Zn0.2Fe2O4 and exist mostly in the form of lamellar structure. Ni0.8Zn0.2LaxFe2-xO4 (X=0-0.1) show the behaviors of the soft magnets and the saturation magnetization (M-s) decreases with the increasing of La3+ content. The electromagnetic property of Ni0.8Zn0.2La0.06Fe1.94O4 is below - 10 dB at 3.1-5.9 GHz and its minimum loss value is - 15.43 dB at 5.1 GHz. Therefore, the introduction of La3+ improves the microwave absorbing properties of Ni0.8Zn0.2Fe2O4. (C) 2015 Elsevier B.V. All rights reserved.