Structural characterization and electrical resistance of the BaPb1-xBixO3 system

The electrical resistance R(T) in function of temperature T, and X-ray powder diffraction (XRD) patterns of polycrystalline samples of the BaPb1-xBixO3 system have been described. R(T) measurements of single phase samples show that BaPbO3 exhibits metal-like properties, and that the system exhibits superconductivity in the 0.005 < x < 0.30 range, but insulating properties for x > 0.30. A careful analysis of the onset of the critical temperature (T-C) reveals its strong dependence on the sample composition in the range 0.005 < x < 0.30 which may be related to the superconducting volume fraction ultimately leading to connected or disconnected superconducting clusters, similar to those observed in granular superconductors.