Optical, impedance, and relaxation response of Fe3+ doped double perovskite solid solution

Abstract

In this report, the effect of Fe3+-incorporation on the crystal structure, vibrational, optical, impedance, modulus, and ferroelectric responses of BaBi1.8Fe0.2TiO6 was discussed. According to XRD and SEM studies, the crystal structure is monoclinic single-phase polycrystalline. The vibrational modes identification from the FTIR spectrum concedes different modes of symmetric and/or antisymmetric vibrations which are usual characteristics of perovskite compounds. The UV-visible study outlines strong absorption and weak reflection near UV and the visible spectrum has a cutoff wavelength of 560 nm. The Tauc and Wood relation estimated the direct band gap energy in the absorbance spectra is 2.70 eV, while the diffused reflectance spectroscopy (DRS) method revealed its value in the reflectance spectra as Eg = 2.84 eV. The resulting bandgap energies suggest that they could be used in photocatalysis. The impedance and modulus analysis supports the semiconducting nature and non-Debye kind relaxation phenomenon in the compound. The PE hysteresis loop with non-zero remanent polarization indicates the material's ferroelectric property, which is suitable for memory storage applications.