Impedance studies of La2Mo2-xSnxO 9-δ oxide ion conductors

Abstract

A series of compounds La2Mo2-xSnxO 9-δ (x=0-0.3) have been synthesized by solid-state reaction technique. Materials have been characterized by XRD, SEM, DSC and impedance study. In the temperature regime 520 °C-590 °C, the specimens with x ≤0.05 have the conductivity higher than La2Mo2O 9. Conductivity of Sn-doped compound decreases consistently with increasing Sn-doping, compared to the undoped compound both below and above phase transition, barring the specimens with x≤0.05, where conductivity values remains almost same as that of undoped specimen in high temperature region. In the intermediate temperature regime (520 °C-590 °C), the conductivity of doped compounds increases for x≤0.05 as compared to parent compound. Also, there is no indication of phase stabilization with Sn-doping in this compound even with the highest doping level, x=0.3. Electric modulus analysis suggests that thermally activated oxygen ion hopping mechanism is responsible for the conduction in Sn-doped compound. © The Chinese Society for Metals and Springer-Verlag Berlin Heidelberg.