Electrical, structural, magnetic and transport properties of Zn2BaFe16O27 doped with Cu2+

Series of polycrystalline samples of Zn2-xCuxBaFe16O27 were prepared by usual ceramic methods, where x=0.0, 0.4, 0.6, 0.8, 1.0, 1.4. X-ray analysis done at room temperature using CoKα with λ=1.790 A confirms the presence of W-type hexaferrite phase structure. Saturation magnetization and hysteresis loops curves measurements at room temperature were studied as a function of Cu2+ substitution. It can be seen that the Cu2+ content slightly decreases the saturation magnetization from 25 to 20 emu g-1; all hysteresis loops are closed, which indicates low anisotropy field and low saturation magnetization field. The dc conductivity and thermoelectric power were measured in a range from room temperature up to T=750 K for all samples. The thermoelectric power decreases on increasing Cu2+ content, and the conductivity increases with temperature. The value of the charge-carrier concentration increases by increasing the temperature and Cu2+ content