The Effect of Tungsten Nanoparticles on Superconducting of The Compound Bi2-xPb0.3WXSr2Ca2Cu3O10+δ

By using a conventional solid-state reaction technique, a group of the superconducting samples with nominal composition Bi2-xPb0.3WxSr2Ca2Cu3O10±δ with (0≤x≤0.5) sintered at 840ᵒC for 140h in the air have been prepared. The effect substitution of tungsten nanoparticles on the physical properties of Bi sites was studied. X-ray diffraction (XRD) studies showed that all our samples are polycrystalline with orthorhombic structures and presence two phases: high-Tc phase (2223), low-Tc phase (2212) and an impurity phase Some impurities likeSr2Ca2Cu7Oδ, CaO  and WO . In the prepared samples the lattice parameter values and the volume fraction of high-Tc phase are calculated. Electrical resistivity measurements show that the values of critical temperature Tc increase with tungsten content. The highest transition temperature, Tc, obtained for Bi2-xPb0.3WXSr2Ca2Cu3O10+δ composition was 191.8K with x=0.3.