The effect of Pr substitution at sr sites in 110K phase of (Bi-Pb)-Sr-Ca-Cu-O superconducting ceramics / Nazarin Nordin

The effect of magnetic Praseodymium (Pr) substitutional doping at varying concentration
into the Strontium (Sr) site in the Bi-Sr-Ca-Cu-0 (BSCCO) high temperature
superconductor is investigated. The samples are prepared via solid state reaction method
and underwent sintering, annealing and resintering process. The two measured properties
are the electrical and the structural properties according to the stoichiometric formula
(Bii6Pbo.4)-(Sri.JtPrt)2-Ca2-Cu3-05 where x = 0.0 - 0.5. For all series of doping
concentration, x = 0.0 - 0.5, Tc (onset) decreased for x = 0.1, then slightly increased at x =
0.2. The Tc then gradually decreased as x is increased and approaches zero as x > 0.5.
The onset of critical temperature Tc and zero resistance critical temperature Tc (R=O) as x
increases indicated the superconductivity destructive trend. Interestingly, at x = 0.2, the
destructive trend was reversed, but as x > 0.2, critical transition temperature is lowered.
Critical current density, jc was also optimised for x = 0.2 samples. Longer sintering and
annealing also improves the Tc and this is shown in x - 0.2 sample. At x = 0.2 sample,
the Tc (onset) for sintered, annealed (at 820 °C) and resintered samples are nearly
identical to pure sample.