Tailoring the structural and magnetic traits of copper modified BaFe12O19 nanostructured hexaferrites for recording media application

Abstract

Barium nanohexaferrites, with a chemical composition of Ba1-0.5xCu0.5xFe12O19 (x = 0.0, 0.1, 0.2, 0.3) have been successfully produced using the sol–gel auto-combustion approach for tuning its structural, morphological, optical and magnetic properties. The current work has been carried out to control the coercivity of synthesized specimens, with the modification of copper ions at the barium sites of BaFe12O19 hexaferrites. The XRD patterns of synthesized specimens’ shows the formational of hexagonal-like crystal structure with P63/mmc space geometry. In the XRD diffraction patterns, the characteristic peaks (110), (008), (107), (114), (108), (203), (205), (206), (1011), (300), (217), (2011), (220), (2014)along with some impurity phases of hematite (α-Fe2O3) were observed. The crystallite size “D” was estimated from the observed XRD patterns using the Debye-Scherrer formula in the range of 41.94–83.91 nm respectively. The FESEM studies of the BM2 and BM3 specimens reveal the presence of agglomerated grains with a hexagonal shape and an average size of ∼ 277 and ∼ 469 nm respectively. The energy dispersive X-ray spectra of synthesized nanohexaferrites shows only peaks of copper, iron, barium, and oxygen which clearly confirms the higher purity of pure and doped barium hexagonal nanoferrites. The transmission electron micrograph of BM1 nanohexaferrite illustrates the production of the nanoparticles that are agglomeratedand spherical, and have an average particle size of 53.32 nm. The Raman spectrum of undoped and copper doped BaFe12O19 hexagonal nanoferrites shows the formation of seven Raman active vibrational modes in the frequency range of 200–800 cm−1. At room temperature (300 K), the magnetic traits of the produced barium hexagonal nanoferrites were measured, and using these measurements, a variety of magnetic parameters (Ms, Hc, Mr, and Ha) were reported. The value of saturation magnetization (Ms) increases from 37.75 emu/g to 59.97 emu/g with increased low copper content up to x = 0.1. In contrast, with the increasing copper content up to x = 0.3, the value of Ms shows a decline to 28.31 emu/g. In this work, admirable values of Ms (28.31–59.97 emu/g) and Hc (684–2563 Oe) were obtained, making these nanohexaferrites as beneficial candidates for the recording media and EMI shielding applications.