Structural and Magnetic Properties of Y³⁺ Doped Ni–Cu–Co Ferrites Prepared by Sol–Gel Auto‐Combustion Method

Abstract

In this work, rare earth Y 3þ ion doped Ni 0.2 Cu 0.2 Co 0.6 Fe 2Àx Y x O 4 (x ¼ 0.0, 0.025, 0.05, 0.075, 0.1) ferrite nanoparticles are synthesized by sol-gel autocombustion technology. High purity metal nitrates and citric acid are used as precursor solutions, and citric acid is used as a complexing agent. The X-ray diffraction (XRD) analysis, Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-ray (EDX) spectroscopy, and vibrating sample magnetometer (VSM) measurements are used to investigate the effect of Y 3þ doping on the structure and magnetic properties of the samples. The analysis of the XRD patterns confirms that all the samples showed cubic spinel structure. The FT-IR also confirms the spinel structure of ferrite, and with the increase of Y 3þ ion content, the peak of the Fe-O bond moved to high frequency. It has been proved that the synthesized ferrite has pure phase and structure by EDX, and Y 3þ -doping is successfully achieved. The magnetic parameters of the samples are measured by VSM at room temperature with a maximum magnetic field of 1 T. By characterization with VSM it can be found that saturation magnetization and remanent magnetization increase first and then decrease with increasing doping amount of Y 3þ ions. Compared with pure sample and other doped samples, the best magnetic properties are obtained when the doping amount of Y 3þ ions is x ¼ 0.025.