Influence of A‐Site Doping on the Local Structure and Magnetic Behavior of BiFeO3 Nanoparticles Investigated by X‐Ray Absorption Fine Structure Spectroscopy

Abstract

Structural transformation and magnetic change of pure and 1% La/Nd‐doped multiferroic BiFeO3 (BFO) nanoparticles are presented to study the influence of introducing rare‐earth elements at the A‐site in BFO. All samples are successfully produced by the conventional hydrothermal method. Scanning electron microscopy picture demonstrates that doping has an impact on the surface and size of particles, and the magnetic properties of BFO also are improved, even significant ferromagnetism is observed in the Nd‐doped sample. Though the room‐temperature X‐ray diffraction patterns reveal the rhombohedral R3c symmetry for all samples, further identified by the Bi L3‐edge and Fe K‐edge X‐ray absorption fine structure (XAFS) spectra, the nanoscale secondary orthorhombic phase is only detected in Bi0.99Nd0.01FeO3 when analyzing the doped elements according to the La and Nd L3‐edge XAFS spectra. The different magnetic behavior is speculated to be in connection with the orthorhombic symmetry around the Nd atom.