Structural, electrical, optical and magnetic properties of Bi2-xLaxFeCrO6 (x = 0.4, 0.6) double perovskites for device applications |
Mitrabinda Mahapatra1, Dinesh Kumar Pati1,2, R. K. Parida3, S. Chakroborty4, B. Behera1, R. Padhee1 |
1School of Physics, Sambalpur University, Jyoti Vihar, Burla, Odisha, 768019, India 2Newton College of +2 Science, Debaipali, Sambalpur, Odisha, 768200, India 3Department of Physics, Multifunctional Materials Research Laboratory, ITER, SOA University, Bhubaneswar, Odisha, 751030, India |
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Received: December 12, 2023; Revised: February 28, 2024 Accepted: March 30, 2024. Published online: April 23, 2024. |
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ABSTRACT |
The novel double perovskite compounds Bi1.6La0.4FeCrO6 and Bi1.4La0.6FeCrO6 are prepared by conventional solid-state method with high energy ball-mill. Numerous characteristics, including optical, structural, electrical, and magnetic were studied and the results were analysed comprehensively. Employing X-ray diffraction, we established that the crystal structure of both the specimens were orthorhombic. Both samples’ strain and crystallite size have been estimated using the Williamson–Hall formalism. For the analysis of the functional groups and molecular vibrations of Bi–O and Fe–O, FTIR spectroscopy is used. Further to study the optical phonon modes RAMAN spectroscopy has been performed. By implementing FESEM the distribution of grains and the grain barriers are studied along with calculation of average grain sizes. Transmission electron microscopy (TEM) images were used to analyze the shape and size of the samples followed by Selected Area Electron Diffraction (SAED) pattern. Energy band gap (Eg) plus Urbach energy are calculated from UV–Vis analysis using DRS method. The existence of narrow energy band gaps makes the samples suitable for O2 emission under the photo-catalytic studies. Some electrical properties like dielectric, impedance, AC conductivity of the compounds were studied. Relaxor behaviour is seen in the dielectric studies for both materials. The temperature dependent role of grain and grain boundary impact was validated by the Nyquist plots and confirms the non-Debye form of relaxation. The existence of overlapping large polaron tunnelling (OLPT) model was confirmed by the temperature change of the frequency exponent (n) from the fitting of Jonscher's equation. The double exchange mechanism provides an explanation for the magnetic properties. |
Key words:
XRD · Microstructure · Photo-catalytic · Dielectric · Conductivity · Ferromagnetic |
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