Synthesis and superconductivity of (Ag)x/CuTl-1223 composites

来源 :Progress in Natural Science:Materials International | 被引量 : 0次 | 上传用户:chen20080310
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Series of(Ag)x/(Cu0.5Tl0.5Ba2Ca2Cu3O10-δ) {(Ag)x/Cu Tl-1223} nano-superconductor composites were synthesized with different concentrations(i.e. x ? 0 4.0 wt%) of silver(Ag) nanoparticles. Low anisotropic Cu Tl-1223 superconducting matrix was prepared by solid-state reaction and Ag nanoparticles were prepared by a sol–gel method separately. The required(Ag)x/Cu Tl-1223 composition was obtained by the inclusion of Ag nanoparticles in Cu Tl-1223 superconducting matrix. Structural, morphological, compositional and superconducting transport properties of these composites were investigated in detail by x-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive x-rays(EDX)spectroscopy and four-point probe electrical resistivity(ρ) measurements. The inclusion of Ag nanoparticles enhanced the superconducting properties without affecting the tetragonal structure of the host Cu Tl-1223 matrix. The improvement in superconducting properties of(Ag)x/Cu Tl-1223 composites is most likely due to enhanced inter-grains coupling and increased superconducting volume fraction after the addition of metallic Ag nanoparticles at the inter-crystallite sites in the samples. The presence of Ag nanoparticles at the grain-boundaries may increase the number of flux pinning centers, which were present in the form of weak-links in the pure Cu Tl-1223 superconducting matrix. Series of (Ag) x / (Cu0.5Tl0.5Ba2Ca2Cu3O10- δ) {(Ag) x / Cu Tl-1223} nano-superconductor composites were synthesized with different concentrations (ie x0.0 wt%) of silver The nanoparticles of low anisotropic Cu Tl-1223 was prepared by solid-state reaction and Ag nanoparticles were prepared by a sol-gel method. The required (Ag) x / Cu Tl-1223 composition was obtained by inclusion of Ag nanoparticles in Cu Tl-1223 superconducting matrix. Structural, morphological, compositional and superconducting transport properties of these composites were investigated in detail by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive x-rays The inclusion of Ag nanoparticles enhanced the superconducting properties without affecting the tetragonal structure of the host Cu Tl-1223 matrix. The improvement in superconducting properties of (Ag) x / Cu Tl-1223 composites is mos t likely due to enhanced inter-grains coupling and increased superconducting volume fraction after the addition of metallic Ag nanoparticles at the inter-crystallite sites in the samples. The presence of Ag nanoparticles at the grain-boundaries may increase the number of flux pinning centers, which were present in the form of weak-links in the pure Cu Tl-1223 superconducting matrix.
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