Ionic conductivity of Bi4Ti0.2V1.8O10.7 polycrystalline ceramics obtained by the polymeric precursor route

Abstract BIMEVOX ceramics presenting the general formula Bi 4 V 2(1− x ) Me 2 x O (11−3 x ) have been synthesized by the polymeric precursor method. The composition that will be described in this work is Bi 4 Ti 0.2 V 1.8 O 10.7 . An analysis of X-ray diffraction patterns revealed that the Bi 4 Ti 0.2 V 1.8 O 10.7 phase was formed by heat-treating the composition at 650 °C for 3 h. Under this thermal treatment condition, the resulting powder presented a surface area of about 5.1 m 2 g −1 . Based on the features of this powder, polycrystalline samples with 98% relative density were obtained by sintering at 880 °C for 8 h. The ionic conductivity of the compact sample was characterized by impedance spectroscopy measurements to separate the dc conductivity of other typical relaxation processes. Ionic conductivity was calculated as 1.48×10 −3 (Ω cm) −1 at a temperature of 473 K, with a carrier activation energy of 0.76 eV. The conductivity values obtained proved to be higher than those of materials prepared by other traditional nonchemical methods.