Dielectric properties of iron doped calcium copper titanate, CaCu2.9Fe0.1Ti4O12

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 (ɛ) 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 ɛ. 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.

► Single phase CCFTO was successfully prepared by novel semi-wet route.
► Substitution of Fe3+ at Cu site in CCTO drastically reduces the dielectric constant.
► XPS results suggest that Fe doped on Cu sites is present as Fe3+ and copper is present as Cu2+ in CCFTO.