Synthesis and Magnetic Characterization of Cu Substituted Barium Hexaferrites

Cu2+ ion substituted nanocrystalline BaFe12O19 [Ba1 − xCuxFe12O19 (0.0 ≤ x ≤ 0.5)] hexaferrite powders were synthesized by sol–gel combustion route and its effects on structure, morphology and magnetic properties of barium hexaferrite (BaFe12O19) were presented. X-Ray Powder Diffraction (XRD), Scanning Electron Microscopy (HR-SEM), Transmission Electron Microscopy (HR-TEM) and Fourier Transform Infrared (FT-IR) analyses revealed the M-type hexagonal structure of all samples. Vibrating sample magnetometer (VSM) analyses showed that all samples have strong ferromagnetic behavior at room temperature. The crystallite size varies in a range of 23.30–35.12 nm. Both HR-SEM and HR-TEM analyses confirmed the hexagonal morphology for products. A minimum of 40.49 and a maximum of 54.36 emu/g estimated specific saturation magnetization (σs) were observed for Ba0.5Cu0.5Fe12O19 and Ba0.9Cu0.1Fe12O19 NPs, respectively. The remnant magnetization (σr) has a minimum value of 21.27 emu/g belonging to Ba0.5Cu0.5Fe12O19 and has a maximum value of 28.15 emu/g belonging to Ba0.7Cu0.3Fe12O19 NPs. The coercive fields are between 1726 Oe and 2853 Oe. Keff (calculated effective anisotropy constants) is changing from 2.31 × 105 to 3.23 × 105 Ergs/g. It was observed that the strong magneto-crystalline anisotropy fields, (Ha) above 11.0 kOe for all samples which confirmed that all samples are hard magnet. Due to their small crystallite size (smaller than 50 nm) and high saturation magnetization, Ba1 − xCuxFe12O19 (0.0 ≤ x ≤ 0.5) nanoparticles can be employed as magnetic recording materials.