Impact of Fe substitution on electrical properties of ErCrO3 semiconductor perovskite ceramic nanoparticles

Abstract ErCr1-xFexO3 (0 ≤ x ≤ 1) (ECFO) perovskite compounds are synthesized by sol-gel auto-combustion processes. The impedance measurements were performed at up to 600 °C temperature, 1 Hz- 1 MHz frequency range. Z ’ vs Z ’ ’ /f plots of x = 0, 1 compounds have shown one relaxation peak corresponds to grain boundary relaxation, whereas x = 0.2, 0.4, 0.6, 0.8 compounds have shown two relaxation peaks up to 300 °C which may be corresponds to the grain and grain boundary relaxations at higher and lower frequencies respectively. The f e ’ value increased with increase in Fe content up to x = 0.6 and thereafter gradually decreased with rise in Fe content, this could be the reason of hopping of charge carriers are very high between Cr3+-Fe3+ in x = 0.6 sample. The grain and grain boundary resistance increases due to increase in B-cite cation radii with increase in Fe3+ substitution in place of Cr3+. The complex modulus plots are also noticed that grain and grain boundary resistance is decreased with increase in temperature, which suggests that the samples are having semiconducting nature. Where x = 1.0 sample have very less conductivity in the order of 10−7(S/m), 8 × 10−5(S/m) at 1 Hz, 1 MHz respectively and whereas x = 0.4 sample have high conductivity in the order of 2 × 10−3(S/m), 10−2(S/m) at 1 Hz, 1 MHz respectively. E a of grain is 0.14eV and 0.08eV for x = 0.2 and x = 0.8 respectively, whereas E a of grain boundary is 0.24eV and 0.07eV for x = 0 and x = 1.0 respectively. Based on these results and as per the earlier reports these materials are more suggestible for giant capacitor, solid oxide fuel cell applications.