Effect of pH on the microstructure and magnetic properties of Cu0.2Co0.8Fe2O4 synthesized by sol–gel method.

The effect of the pH of precursor solution on the microstructure as well as the magnetic properties of Cu_0.2Co_0.8Fe₂O₄ nanoferrite samples, was investigated. The structures of the samples analyzed by X-ray diffraction were all in the cubic spinel phase. The average crystallite size of the samples was obtained by Scherrer's formula to be between 60 and 68 nm, indicating that there is some effect of pH. The cation distribution proves that there is a difference in the ion spacing of the samples synthesized at different pH values. FTIR spectroscopy again verified the spinel structure of the synthesized samples and the absorption peaks were shifted due to the redistribution of cations in the samples at different pH values. Scanning electron microscopy observed that the particle size of the samples gradually decreased with increasing pH, but all were cubic with some degree of agglomeration due to magnetic properties. Elemental analysis yielded a pure phase structure for the samples. The samples are ferromagnetic as can be seen from the hysteresis lines of the samples. The magnetic parameters of the synthesized samples are all maximum at pH = 10, such as residual magnetization strength (Mr = 24.31 emu/g), saturation magnetization strength (M_s = 57.41 emu/g), coercivity (Hc = 751.41 Oe), and so on. The samples can be used in the field of magnetic recording. Highlights: This article uses the sol-gel method which can significantly save time and energy consumption and requires a lower sintering temperature, compared to traditional methods. The prepared samples were characterized using XRD, FTIR, SEM, EDX, and VSM. The experimental results show that the Cu_0.2Co_0.8Fe₂O₄ nano ferrite samples have good structural and magnetic stability. When pH = 10, the magnetic parameters of the synthesized samples are the maximum. This means that these samples can be used in the field of magnetic recording. [ABSTRACT FROM AUTHOR]