ĐÁNH GIÁ CẤU TRÚC VÀ TÍNH CHẤT TỪ CỦA HỆ HẠT NANO PEROVSKITE La1–xNdxFeO3 TỔNG HỢP BẰNG PHƯƠNG PHÁP ĐỒNG KẾT TỦA

Abstract

In this study, a series of neodymium-doped lanthanum perovskite nanoparticles (La_1–xNd_xFeO₃, with x = 0, 0.1, 0.15, and 0.2 based on theoretical stoichiometry) were synthesized using a simple co-precipitation method with 5% NaOH solution as the precipitating agent. The structural and magnetic properties of the synthesized samples were characterized by powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), scanning and transmission electron microscopy (SEM and TEM), and vibrating sample magnetometry (VSM). Single-phase perovskite structures of La_1–xNd_xFeO₃ were formed after calcination of the dried precipitate at 800 °C for 60 minutes. The average crystallite size and unit cell volume were found to decrease with increasing Nd³⁺ doping (D_Scher = 30.71–27.07 nm; V = 242.62–241.41 ų). The synthesized nanoparticles exhibited spherical to near-spherical morphology with particle sizes ranging from 30 to 50 nm. Both LaFeO₃ and La_0.8Nd_0.2FeO₃ samples exhibited soft ferromagnetic behavior, characterized by nearly-zero coercivity (H_c, Oe) and remanent magnetization (M_r, emu·g^–1), while showing relatively high saturation magnetization (M_s = 0.13–0.19 emu·g^–1).