Structural, dielectric and magnetic properties of Nd-doped Co 2Z-type hexaferrites

Abstract

Z-type hexaferrites doped with Nd 3+, Ba 3− x Nd x Co 2Fe 24O 41 ( x = 0, 0.05, 0.10, 0.15, and 0.25), were prepared by solid-state reaction. The effect of the Nd 3+ ions substitution for Ba 2+ ions on the microstructure and electromagnetic properties of the samples was investigated. The results reveal that an important modification of microstructure, complex permeability, complex permittivity, and static magnetic properties can be obtained by introducing a relatively small amount of Nd 3+ instead of Ba 2+. SEM image shows that the grains of the ferrites doped with Nd 3+ were smaller, more perfect and homogeneous than that of the pure ferrite. The real part ( ɛ′) of complex permittivity and imaginary part ( ɛ″) increase at first, and then decrease with increasing Nd content. At low frequency, the imaginary part μ″ of complex permeability decreases with Nd content and then increases when frequency is above 7.0 GHz. The magnetization ( M s ) and the coercivity ( H c ) are 79.38 emu g −1 and 36.94 Oe for Ba 2.75Nd 0.25Co 2Fe 24O 41. The data of magnetism show that the ferrite doped with Nd 3+ ions is a better soft magnetic material due to the higher magnetization and lower coercivity.