Dielectric properties of iron doped calcium copper titanate, CaCu 2.9Fe0.1Ti4O12

Abstract

CaCu2.9Fe0.1Ti4O12 (CCFTO) has been prepared by a novel semi-wet route and its dielectric properties have been studied in the temperature range 300-500 K. It is found that dielectric constant (ε) decreases drastically in the frequency range 100 Hz to 1 MHz. Complex plane impedance and modulus analysis was done to understand this drastic decrease in ε. Oxidation state of various ions was studied using X-ray photoelectron spectroscopy (XPS). The decrease in the permittivity of CCFTO can be attributed to two factors: the suppression of the Ca/Cu disorder in CCFTO which is observed in CaCu3Ti4O12 (CCTO) and the absence of the grain boundary internal barrier layer capacitance mechanism. © 2011 Elsevier B.V. All rights reserved.