Synthesis and characterization of Ag5-xPb2O6-δ

Ag4.64Pb2O5.87, a silver and oxygen defects phase of Ag5Pb2O6, was prepared by solid state reaction of Ag2O and PbO at 773 K in O2 of 1.2 MPa. The crystal structure was analyzed by the Rietveld method using X-ray powder diffraction data. The c-axis length changed from 6.427 to 6.433 Angst in 0.25<x<0.50 while the a-axis length was almost constant around 5.942 Angst. Ag4.64Pb2O5.87 exhibited metallic temperature dependence of electrical resistivity in the temperature range of 10-400 K. The value of the resistivity was in the order of 10-4 Ω cm. The Seebeck coefficient ranged from -4 to 0 μV/K below 300 K, which revealed that the main conductive carrier is electron. Diamagnetism of the order of 10-7 emu/g was measured at 5-350 K