Effect of rare-earth (Sm, Ce, and La) ions doping on the lattice structure and magnetic properties of Zn- Ba-Co ferrites by sol-gel auto-combustion method

摘要

Rare-earth ions doped Zn-Ba-Co ferrite with chemical composition Zn_(0.1)Ba_(0.2-) Co_(0.7)Fe_(2-x)RE_xO_4 (Sm, Ce, La, and x = 0.02) were prepared by sol-gel auto-combustion method. X-ray diffraction (XRD) results confirmed that rare-earth ions doped Zn-Ba-Co ferrite had spinel structure. The average crystallite sizes were found to be between 21.1 and 31.0 nm, which were calculated by Scherrer's formula. The Fourier transform infrared (FT-IR) spectra also confirmed the formation of spinel structure. The morphology of prepared samples was observed by scanning electron microscope (SEM) and transmission electron microscope (TEM). The chemical compositions of prepared samples were analyzed by energy dispersive spectrometer (EDS). It is confirmed that the elements of samples are composed of Zn, Ba, Co, Fe, O, and rare-earth elements. The magnetic parameters of the samples are measured by vibrating sample mag-netometer (VSM) at room temperature. It can be clearly observed that the sat-uration magnetization (Ms), remanent magnetization (Mr), and coercivity (Hc) varied with the doping of different rare-earth ions. La~(3+) doped Zn-Ba-Co sample had the highest Ms. It showed that rare-earth ions had greater effects on the magnetic properties of Zn-Ba-Co ferrite.