Neodymium-Engineered Relaxor Bismuth Ferrite Nanoparticles: Structural Tuning and Dielectric Enhancement for Efficient Sensor Applications

Abstract

This paper investigates the synthesis and properties of neodymium-doped bismuth ferrite (BiFeO₃) nanoparticles, highlighting their enhanced functionality for advanced applications.The nanoparticles were successfully synthesized with a sol-gel method, where neodymium (Nd) was substituted onto the A-site in concentrations ranging from 6% to 10%. A comprehensive analysis of the structural, morphological, and dielectric properties was conducted. X-ray diffraction (XRD) and Rietveld refinement confirmed that all samples maintained a rhombohedral crystal structure with the R3c space group. The incorporation of Nd cations was found to significantly alter the intrinsic distortion of the FeO₆ octahedra within the lattice, which is identified as a primary mechanism for property enhancement. Morphological studies showed that the nanoparticles were uniform, with grain sizes between 160 nm and 195 nm. Furthermore, XPS confirmed the presence of Fe²⁺ ions, which are directly linked to the improved ferroelectric performance. An extensive study of the dielectric properties revealed a change in the electrical conduction mechanism with temperature and notable relaxor behavior.A reduction in the Néel temperature and increased thermal sensitivity were also detected. These remarkable findings demonstrate that Nd substitution is highly effective in tailoring the properties of bismuth ferrite, making these modified nanoparticles excellent candidates for next-generation devices.