Enhancing oxide-ionic conductivity of Ba3Mo1+xNb1-2xGexO8.5 at intermediate temperatures: the effect of site-selective Ge4+-substitution

Significant oxide-ionic conductivity has been recently reported for a family of cation-deficient hexagonal perovskite derivatives Ba3M2O8.5 (M = Mo/W6+ and Nb5+/V5+). Herein, the strong 4-fold coordination geometry preferred Ge4+ ions...

Hexagonal perovskite derivatives: a new direction in the design of oxide ion conducting materials

A structural rearrangement is observed in Ba3MM′O8.5hexagonal perovskites above 300 °C, which enhances the oxide ionic conductivity.

Oxide ionic conductivity and microstructures of Pr and Sm co-doped CeO2-based systems

The compositions Ce0.80Sm0.2-xPrxO2-δ (x=0-0.12) were prepared through the citrate-nitrate method. The synthesized Pr3+ and Sm3+ co-doped ceria powders with different compositions were calcined at 600°C for 3 h. Phase structure of the calcined powders was characterized by X-Ray diffraction (XRD) analysis.All the calcined samples were found to be ceria based solid solutions of fluorite type structures. The morphology examinations were carried out by scanning electron microscopy (SEM) analysis. Relative density of more than 91% of the theoretical can be achieved by sintering the Ce0.80Sm0.2-xPrxO2-δ pellets at 1400°C for 6 h. The two-probe a.c. impedance spectroscopy was used to study the ionic conductivity of the doped ceria samples. The Ce0.80Sm0.80Pr0.12O1.90 composition showed the highest total ionic conductivity value which is 2.39 × 10−2 S/cm at 600°C.

Effects of Pt dispersion on electronic and oxide ionic conductivity in Pr1.90Ni0.71Cu0.24Ga0.05O4

Pt dispersion in Pr2NiO4 based oxides formed compressed strain and electrical conductivity decreases, however, the oxide ion conductivity increases by the compressed strain due to the decreased hole and the increased interstitial oxygen concentration.