Study of Structural, Dielectric, and Electrical Properties of Gadolinium-Modified Bismuth Lanthanum Oxide

Abstract

In this article, synthesis (solid-state reaction) and characterization (structure, microstructure, and electrical) of the gadolinium (Gd) modified bismuth lanthanum oxide (LaBi0.9Gd0.1O3, and LBGO) are reported. Rietveld refinement of the x-ray diffraction (XRD) data was done using MAUD software, which adopts an orthorhombic crystal symmetry. The average crystallite size in the prepared sample was calculated using Scherer’s relation. Scanning electron microscope (SEM) micrograph analysis reveals that grains are uniformly distributed over the sample’s surface through well-defined grain boundaries so that a dense sample is formed, which may be a possible reason for elevated dielectric properties. The study of energy dispersive analysis of the x-ray (EDX) spectrum confirms the presence of all constituent elements (Bi, La, Gd, and O) in the studied sample. The presence of Maxwell–Wagner type of dispersion is confirmed from the study of dielectric properties as a function of frequency. The analysis of the modulus study confirms the presence of a non-Debye type of relaxation. The negative temperature coefficient of resistance (NTCR) nature of the sample is confirmed by the impedance study. The study of ac conductivity suggests the presence of a thermally activated relaxation process in the studied sample. Again, analysis of the Nyquist plots confirms the semiconducting character and may be suitable for some energy storage devices applications.