Abstract:
The (Bi2O3)1−x−y(Gd2O3)x(Lu2O3)y material compounds were prepared by using
the solid-state reaction technique under normal air conditions. The heat treatments of
the ternary samples were performed firstly at 800 °C for 48 h and then at 750 °C for
100 h. The structural, morphological, and magnetic properties of the materials were
characterized by X-ray powder diffraction (XRD), scanning electron microscope, and
a Quantum Design PPMS-9T system, respectively. From the XRD results, it was found
that the phases of all of the samples consisted of the fluorite-type face-centered cubic
δ-Bi2O3 phase. It was observed that the microstructure of the samples is uniformly dis tributed on the samples’ surface. The temperature dependence of magnetization (M–T)
measurements showed that the magnetization rose sharply at the critical temperature.
The calculated critical temperature values vary from 22.19 to 56.61 K for the samples.
All of the samples displayed the paramagnetic behavior. The paramagnetic behavior
started from 300 K to very low temperature which varied from 22.19 to 56.61 K. The
coercive rise on the magnetization below 22.19 K or 56.61 K with decreasing tem perature causes a phase transformation in the δ-Bi2O3 system. This sudden increment
was considered as a ferromagnetic or ferrimagnetic phase transition