THE EFFECT OF 5% Sb DOPING ON HIGH Tc SUPERCONDUCTIVITY IN (Bi, Pb)2Sr2Ca2Cu3Oy COMPOUND
Abstract
The effect of a small amount of Sb doping (5%) on the formation of the high temperature superconducting phase has been investigated on the Bi1.5Pb0.5Sr2Ca2Cu3Oy compound. It is observed that at 860°C the Tc zero value depends on the sintering time. It first increases to a maximum value of 96 K and then decreases to a stable lowest value of 88 K. The samples have been characterized by X-ray diffraction (XRD), four probe electrical resistance and current density measurements. The XRD revealed the presence of two phases: an orthorhombic high-Tc 2223 phases with lattice constants a = 5.395 Å, b = 5.508 Å, c = 37.0422 Å and another tetragonal low-Tc 2212 phase with lattice constants a = b = 5.419 Å, c = 30.832 Å.