Phase, microstructure and conductivity of electron-doped Ba1−xLaxPbO3 ceramics

Electron-doped Ba1−xLaxPbO3 (x≤0.30) ceramics have been prepared; the phase, microstructure, and conductivity have been investigated as functions of x value and sintering temperature. The solution limit is close to x=0.15. Sintering temperature plays an important role in determining phase purity and microstructure (grain size and porosity). All single-phase ceramics show metallic nature, which is related to two main factors. On the one hand, electron-doping increases the resistivity from 10−8 Ω m for the composition with x=0 to 10−5 Ω m for others with x≠0. On the other hand, the effect of grain size and porosity on resistivity is considerable, though not as significant as that of electron-doping. The structure–property relationship is discussed in detail. Our results may be helpful for further work on BaPbO3-based materials.