High thermal stability and colossal permittivity of novel solid solution LaFeO3/CaTiO3

摘要: Abstract This study presents the novel (LaFeO3)(1-m)(CaTiO3)m (m = 0, 0.1, 0.3 and 0.5 in weight fraction) solid solutions. These materials were obtained by conventional solid-state reaction between LaFeO3 (LFO) CaTiO3 (CTO) perovskite phases despite favorable conditions for composite formation. The X-Ray diffraction (XRD) confirmed solution formation isomorphic substitution of La3+ Fe3+ Ca2+ Ti4+, respectively. electric properties studied impedance spectroscopy (IS) from 1 Hz to 10 MHz range as a function temperature composition. imaginary part (Z″), real permittivity (e′), dielectric loss (tanδ), activation energy (Ea), conductivity ac-type (σ′ac), capacitance (C) coefficient (TCC), determined analysis. results demonstrate that depend on m, frequency (f), (T). colossal values e′ at 30 °C verified compositions m = 0, 0.1 (2.59 × 104, 3.90 × 104 5.7 × 103, respectively). sample LFO0.9CTO0.1 had divergent behavior other samples did not follow tendency with higher e′, tanδ lower value Ea series. For this sample, optimal 18.5 kHz 40 °C, indicates ionic increases thermal stability LFO matrix, resulting high considerable stability, especially LFO0.9CTO0.1.