Structure, Magnetic Properties and Electromagnetic Wave Absorption Properties of Bi1-xYxFeO3

Abstract

Rare earth ion doping in ferrites has been recognized as an effective method for modulating the dielectric and magnetic properties of ferrites. In this work, Y-doped BiFeO₃ samples were successfully synthesized via the sol-gel method. The influence of Y doping concentration (x = 0, 0.05, 0.10, and 0.15) on the crystal structure, microstructure, magnetic properties, and electromagnetic wave absorption (EMW) performance of BiFeO₃ was systematically examined. XRD results indicate a phase transition in BiFeO₃ from R3c (rhombohedral) to Pbnm (orthorhombic) with increasing Y doping concentration, accompanied by reductions in lattice parameters, unit cell volume, and grain size. The saturation magnetization increases first and then decreases with the increase of Y³⁺ doping content, and reaches the maximum value when x = 0.10. Rietveld refinement reveals that Y³⁺ doping induces tilting of FeO₆ octahedra, which is attributed to the enhancement of saturation magnetization. A synergistic effect of dielectric and magnetic losses leads to a minimum reflection loss of –35.19 dB at 2.2 mm and a maximum effective absorption bandwidth of 3.29 GHz for Bi_0.90Y_0.10FeO₃.