Synthesis and Characterization of the (BiFeO3)0.5–(CaTiO3)0.5 Solid Solution for Some Device Applications

Abstract

In this paper, the synthesis (solid-state reaction) and characterization (structural, dielectric, electrical, and optical) of the (BiFeO3)[Formula: see text]–(CaTiO3)[Formula: see text] (BFCTO) are reported. The structural analysis suggests a distorted rhombohedral crystal symmetry (#R-3m) with average crystallite of 93.2[Formula: see text]nm and lattice strain of 0.105%. The scanning electron microscopy (SEM) and energy dispersive microstructural analysis X-ray (EDAX) analyses suggest that the grains are uniformly distributed with well-defined grain boundaries and the presence of all constituent elements, respectively. The average grain size is about [Formula: see text]m as calculated from the ImageJ software. Both the temperature and the frequency-dependent dielectric study predict high dielectric constant of 9000 at 1[Formula: see text]kHz, low dielectric loss, the phase transition from ferroelectric to paraelectric at 410∘C, and negative temperature coefficient of resistance (NTCR) character. The impedance spectroscopy provides the effect of grains and grain boundaries on the conductivity mechanism and exhibits the non-Debye type of relaxation. The decreasing radius of semicircular arcs with temperature in both Nyquist and Cole–Cole plots supports the NTCR and thermally activated conduction mechanism. The polarization–electric field (P–E) loop study confirms the ferroelectric character of the sample. The study of the [Formula: see text]–[Formula: see text] plot suggests the leakage current in the mA range and ohmic conducting nature. The Fourier transform infrared spectroscopy (FTIR) spectrum suggests the presence of all constituent elements, whereas the bandgap energy from UV–Visible study is about 1.43[Formula: see text]eV, which is useful in photovoltaic applications.