Electrospun Nanofibers (1D) versus Co-precipitated Nanoparticles (0D) of BaFe12-xAlxO19: A Comparative Study of Nanostructure, Crystallinity, and Magnetic Properties

Barium hexaferrite (BaFe 12 O 19 , BaM), a M-type hexaferrite, has been used in various applications due to its notable properties. Partial substitution of Fe 3 + ions with non-magnetic cations can alter BaM magnetic behavior by changing the intrinsic spin configuration of the ferrite lattice. This study investigates the impact of Al +3 substitution on the structural and magnetic properties of modified Al-BaM. A series of BaFe 12-x Al x O 19 samples (0.0 ≤ x ≤ 4.0) were synthesized in both nanoparticle and nanofiber morphologies using different fabrication routes derived from similar precursor sources. The highest coercivity value Hc (6005 Oe) was achieved for BaAl 4 Fe 8 O 19 nanoparticles, with low saturation magnetization Ms (37.39 emu/g). Within the Al-BaM nanofiber series, the highest coercivity Hc (4872 Oe) and lowest saturation magnetization Ms (10.43 emu/g) were achieved at concentration x = 3.5. In sum, the vibrating sample magnetometer (VSM) results showed that the occupancy of Al +3 non-magnetic ions instead of Fe +3 ions in the hosting matrix and the presence of impurities resulted in an explainable change in both coercivity (Hc) and saturation magnetization (Ms) values. NFs and NPs refer to nanofibers and nanoparticles, respectively. • The crystallinity and purity of fabricated Al-BaM nanoparticles are greater than those of Al-BaM nanofibers. • Increased Al-substitution level affected the morphology features for fabricated Al-BaM nanofibers. • The morphology and presence of aluminum in the BaM lattice had affected its magnetic properties significantly.