Structural and Magnetic Properties of Perovskite Functional Nanomaterials La1−xRxFeO3 (R = Co, Al, Nd, Sm) Obtained Using Sol-Gel

Abstract

Perovskite is the largest mineral on earth and has a variety of excellent physical and chemical properties. La1−xRxFeO3 (R = Co, Al, Nd, Sm) were synthesized using the sol-gel method and analyzed by XRD, TG-DTA, and VSM. With the increase in the Co2+ doping content, the diffraction peak drifted in the direction of a larger angle. The grain size of La1−xRxFeO3(R = Co) is mainly concentrated between 50.7 and 133.5 nm. As the concentration of Co2+ increased, the magnetic loop area and magnetization increased. La1−xRxFeO3(R = Al) is an orthorhombic perovskite structure, the grain size decreased with the increase in Al3+ doping concentration, and the minimum crystallite is 17.9 nm. The magnetic loop area and magnetization increased with the increase in Al3+ ion concentration. The enclosed area of the M-H curve of the sample decreased, and the ferromagnetic order gradually weakened and tended to be antiferromagnetic, which may be due to the increase in sintering temperature, decrease in the iron oxide composition, and changes in the magnetic properties. Proper doping can improve the magnetization of La1−xRxFeO3(R = Nd), refine the particles, and obtain better magnetic performance. As the Nd3+ ion concentration increased, the magnetic properties of the samples increased. Ms of La0.85Co0.15FeO3 prepared by different calcination time increases with the increase in calcination time. As the Sm3+ ion concentration increased, the magnetic properties of the samples increased. Proper doping can improve the magnetization of La1−xRxFeO3(R = Sm), refine the particles, and generate better magnetic performance.