Synthesis and Paraconductivity Studies of Fe–Pd Nanoparticles Added Cu0.5Tl0.5Ba2Ca3Cu4 O 12−δ Superconductors

Abstract

Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ /(Fe-Pd 0, 0.5, 1.0, 1.5 %) superconductors are prepared at normal pressure by using three-step method. Alloy of Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ /(Fe-Pd 1 %) have shown maximum increase in the magnitude of superconductivity. Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ /(Fe-Pd 0, 0.5, 1.0, 1.5 %) samples have shown T c (R = 0) around 106, 105.3, 102, and 100 K and the onset of diamagnetism around 113, 110, 102, and 105 K, respectively. A comparison of X-ray diffraction (XRD) scans of Fe-Pd nanoparticles with Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ /(Fe-Pd 0.5, 1.0, 1.5 %) superconducting samples have shown that the nanoparticles of Fe-Pd are quite stable in the matrix of Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ samples even after repeated firing at 890 • C. With increase addition of Fe-Pd nanoparticles, the axes length increases, showing some inclusion of nanoparticle into the unit cell of Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ samples from the termination ends of crystal. The inclusion of Fe-Pd in the superconducting Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ grains is also evidenced in Fourier transform infrared spectroscopy (FTIR) absorption measurements. The Fe-Pd nanoparticles added in Cu 0.5 Tl 0.5 Ba 2 Ca 3 Cu 4 O 12−δ samples have been found to decrease the population of inter-grain voids that is found to increase the coherence length along the c-axis and the