Enhancement of (Bi,Pb)-2223 HTS Formation by Boron-Doping

Influence of boron-doping on the superconducting properties of (Bi,Pb)-2223 HTS ceramics prepared in an alumina crucibles has been investigated. X-ray diffraction, resistivity, and AC susceptibility measurements were performed on the undoped and boron-doped compounds. Obtained results have shown that B 2 O 3 addition in the Bi 1.7 Pb 0.3 Ca 2 Sr 2 Cu 3 O y precursor enhances the formation of high- T c phase. The boron-doped samples with starting composition Bi 1.7 Pb 0.3 Ca 2 Sr 2 Cu 3 B x O y ( x =0.05 and 0.5) reveal significant improvement in the zero resistivity temperature compared to the undoped sample (from 72 K up to 100 K). Boron-doping level x =1.5 results in a substantial degradation of the (Bi,Pb)-2223 phase.