POLYMERIC PRECURSOR DERIVED HIGH-TC BISMUTH SUPERCONDUCTORS

Abstract

Two bismuth-based high-T(c) oxide superconductors have been prepared by employing the polymeric citric acid/ethylene glycol (CA/EG) precursors, The polymeric precursors of mixed cations can be converted into X-ray pure Bi2Sr2CaCu2Ox (2212) and Bi1.5Pb0.5Sr2Ca2Cu3Oy (2223) phases with T(c)(zero)s in the range of 76 K and 100-110 K, respectively, and with good stoichiometry control and sample homogeneity. We describe the chemistry involved in the materials processing leading to the formation of bismuth-based superconductors and report the results from materials characterization by differential thermal analysis, resistivity and magnetization measurements.