Effect of ferromagnetic cobalt on characteristics of coercive Aluminium substituted BaFe11.5Al0.5O19 hexaferrites

Abstract

Abstract Magnetic and structural characteristics of M-type barium hexaferrite nanoparticles can be tuned by doping different di or trivalent metal ions. Here BaFe11.5−xAl0.5CoxO19 hexaferrite nanoparticles were synthesized using a sol-gel process, and the influence of doping concentrations on M-type BaFe11.5−xAl0.5CoxO19 hexaferrite nanoparticles was deliberated. The XRD analysis confirms the formation of ferrites successfully. When the doping level increased, the grain dimension (D) initially reduced and then increased. Similarly, the lattice constants ‘a’ and ‘c’ decreased initially and then increased. The findings indicated that the (Mr/Ms) ratio decreased initially as the doping content increased, but at higher doping ranges, it started to rise. At the same time, coercivity (Hc) and magneto-crystalline an-isotropy field (Ha) increased as the doping level increased. Excellent magnetic characteristics were obtained for BaFe11.5−xAl0.5CoxO19 hexaferrites at doping content of (x = 1.5), with magnetic moment 10.80 μ B, saturation magnetization 57.35 emu g−1, and coercivity 5.21 kOe along anisotropic applied field of 1.62 kOe. The findings mentioned above imply that magnetic characteristics of M-type Barium hexaferrites can be significantly improved upon doping of Cobalt against Aluminium substituted hexaferrites, which will make such types of Ba-hexaferrites very useful in various magnetic applications.