The impact of Bi3+ substitution for Y3+ cation on structural, topographical, electrical and thermal behaviour of YFeO3

Abstract

Bismuth Substituted Yttrium orthoferrite nano powders have been prepared by Sol-Gel route by setting the pH value at 9 on pH scale. The room temperature X-ray diffraction patterns confirm the single-phase orthorhombic symmetry with space group Pnma. The Rietveld Refinement fitting through FullProf program provided various geometrical and lattice parameters with moderate value of χ2 and GOF. The particle size (D) has been measured using Scherrer and Williamson Hall methods. 2 and 3-Dimensional surface morphology have been measured using atomic force microscopy (AFM) which also supports the particle size to be of the order of nano meter size. The thermal behaviour has been studied using DTA-TGA techniques in the temperature range from RT to 1223 K which shows sluggish transition near Neel Temperature (644 K) in heating as well as in cooling cycle. These sluggish transitions were also verified using MDSC measurement technique in the temperature range from RT to 773 K which is coherent with DTA curve and clarifying the magnetic transition. The activation energies have been calculated from DC conductivity measurement which lie in the semiconducting zone. The response of current with voltage (I–V characteristics) reflects almost Ohmic nature of the prepared samples. The results are discussed in detail.