Synthesis of Bi-2223 phase using different precursors through different routes and their characterisation

A comparative study of two different precursor reaction path-ways for the preparation of high Tc superconducting Bi-2223 phase (Pb-free and Pb doped) have been reported. In the Pb doped Bi-2223 system excess amounts of CaO and CuO (Bi-2234) were used to improve the Bi-2223 phase formation using the glassy-matrix technique. Single crystals of Bi-2223 were grown by slow cooling technique using KCl as flux. Bi(Pb)-2223 phase also was synthesised using the conventional ceramic technique with two different Pb compositions (Pb=0.35 and 0.40 at%). In order to improve the grain alignment of the ceramic samples, zone melting was carried out at a faster pulling rate (10 mm h−1). Different secondary phases of the synthesised samples were identified from the XRD analysis. The chemical composition of the samples was determined from the ICP analysis and iodometry titration. AC susceptibility studies were done for all the samples and discussed in detail.