Structural, optical, electrical and magnetic characteristics of multiferroic [Pb(Fe0.5Nb0.5)O3]0.3-[(Ca0.2Sr0.8)TiO3]0.7 perovskite ceramic compound

We report a systematic investigation of structural, microstructural, optical, electrical and magnetic properties of [Pb(Fe0.5Nb0.5)O-3](0.3)-[(Ca0.2Sr0.8)TiO3](0.7) compound synthesized by solid-state reaction method. Rietveld analysis proved that the compound crystallizes in pseudocubic phase with a (chi)(2) value of 1.32. Williamson-Hall analysis predicted a tensile strain of 0.00021 and crystallite size of 96.28 nm. The dual oxidation states of Nb, Ti and the presence of oxygen vacancies were analysed by X-ray photoelectron spectroscopy. The Ti-O, O-Ti-O, O-Nb-O and Fe-O vibrations were studied by Fourier transform infrared analysis. The TiO6 octahedral stretching and Nb-O-Fe vibrations related to A(1g) phonon mode of PFN were analysed by Raman spectroscopy. Field emission scanning electron microscopy revealed a dense grain distribution with an average grain size of 3.24369 mu m and purity was confirmed from energy-dispersive X-ray spectroscopy. The narrow band gap and Urbach energy were studied by UV-Visible analysis in the frameworks of absorbance and diffuse reflectance modes. The effect of electronegativity on band gap was studied. Electrical properties were analysed by dielectric constant, loss tangent, complex impedance, ac and dc conductivity analyses. Activation energy analysis showed that conduction is governed by singly ionized oxygen vacancy and relaxation is governed by doubly ionized oxygen vacancy. Room-temperature P-E hysteresis loop analysis revealed a weak ferroelectric behaviour with remnant polarization 0.142 mu C/cm(2). M-H study showed weak ferromagnetism with a magnetic moment of 0.039 emu/g with superimposed paramagnetic component. A paramagnetic doublet with Fe ions having octahedral environment was detected by room-temperature Fe-57 Mossbauer spectroscopy with extracted hyper fine parameters: width [Gamma(mm/s)] = 0.31 +/- 0.02, isomer shift [(delta E) (mm/s)] = 0.38 +/- 0.02 and quadrupole splitting [(Delta E-Q) (mm/s)] = 0.29 +/- 0.03. The current article provides a detail insight about the synthesis and multifunctional characterizations of a new multiferroic compound which can be used for photocatalytic applications. The presence of weak multiferroicity is an interesting outcome of the current investigation for its electro-optical applications. The dielectric analysis indicates the potential applications of the compound in high-temperature storage applications.