High magnetic performance in Al-substituted BaFe12O19 by a wet chemical process

A wet chemical process has prepared Al-substituted barium ferrite nanoparticles BaFe11AlO19. Structural and magnetic properties of BaFe11AlO19 powers were characterized with an X-ray diffractometer, a vibrating sample magnetometer, and a Mossbauer spectroscopy. The results of X-ray diffraction measurements showed that the BaFe11AlO19 had an M-type hexagonal structure with lattice parameters a(0) = 5.871, c(0) = 23.190 Angstrom and X-ray density rho(x) = 5.194 g/cm(3). The particle size was 37 nm. Mossbauer spectra of BaFe11AlO19 measured at various absorber temperatures of 15-800 K. Its Curie temperature is found to be 700 +/- 5 K. The average hyperfine field H-hf(T) of the BaFe11AlO19 shows a temperature dependence of [H-hf(T)-H-hf(0)]/H-hf(0) = -0.34(T/T-c)(5/2) -0.05(T/T-c)(3/2) for T/T-c < 0.7, indicative of spin-wave excitation. The anisotropy fields H-A was 21.2 kOe and anisotropy constant K-1 was 2.86 x 10(6) erg/cm(3) at room temperature, as determined the law of approach to saturation (LAS). The saturation magnetization was 44.3 emu/g and the coercivity was 7.56 kOe.