Synthesis and Electrical Properties of Ba_1-xSr_xPbO_3-z with the Perovskite Structure

Abstract

The preparation, structure and electrical properties of Ba_1-xSrxPbO_3-z are reported. These phases all have orthorhombic perovskite structure whose space group, however, changes at around x=0.3-0.4 from Inma (BaPbO₃ side) to Pnma (SrPbO₃ side). The transport property also changes from metallic (Inma) to semiconductive (Pnma) at this point. Wide range of oxygen deficiency was realized in this system by changing the synthetic oxygen pressure. With the increase of oxygen deficiency the metallic conductivity region expanded to the Sr-rich side. The doping of La₃₊ in A site was also effective to change the system to metallic.