Doping of Pb-Oxides into Bi-Based Superconductors

We prepared a Bi-based superconductor using a variety of Pb-oxides and found that the samples prepared at temperatures above 830°C using Pb-oxides contained the 2223-phase; especially, the samples prepared at temperatures above 855°C using Pb2O3 showed a zero-resistance temperature above 90K. The XRD results showed that the volume fraction of the 2223-phase superconductor was increased by doping with Pb2O3. The chemical bonding nature of the samples which prepared using Pb2O3 was different from those of the samples prepared using other Pb-oxides. The results may indicate that Pb2O3 has a peculiar effect on the formation of a 2223-phase.