Abstract
? 2022 Elsevier B.V.The perovskite structure materials used as an oxygen ion conductor in solid oxide fuel cells have been widely studied. Here, we report novel property of NaNbO3-based ceramics about oxygen ion conduction. The grain size is significantly increased as well as the structural symmetry is enhanced with bismuth doping. Based on the analysis of AC impedance in serial pO2, nearly pure oxide ions conduction characteristic was realized in Na0.4Bi0.2NbO3 composition. Remarkably, electrical conductivity of Na0.4Bi0.2NbO3 sharply increased 3 orders of magnitude to 0.01 S/cm at 700 °C compared to that of NaNbO3 oxides. This study not only discovered the novel ionic conductor properties of Na0.4Bi0.2NbO3, but also provided a new candidate for the solid electrolyte of medium-temperature solid oxide fuel cells (IT-SOFCs).
NSTL
Elsevier