A comparative study on the influence of the addition of different nano-oxide particles on the thermopower of (Bi,Pb)-2223 superconductor

摘要

Solid-state reaction technique was used to prepare superconductor samples with nominal composition of (SnO2)(x)(Bi,Pb)-2223 and (NiO)(x)(Bi,Pb)-2223, where 0.0x0.2wt%. The prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The impact of SnO2 and NiO nanoparticles addition on the thermopower of (Bi,Pb)-2223 was measured using a standard differential technique. The Seebeck coefficient values in the presence of NiO nanoparticles were about 5-37.9% higher than those obtained with the addition of SnO2 nanoparticles. Higher values of Seebeck coefficients result in a wide variety of applications of these superconductors such as electronics and thermoelectric devices. The obtained results were analyzed according to the two-band model (Fermi-liquid model) and the two-band model with an extra linear term. The Fermi velocity (upsilon(F)), Fermi energy, Fermi temperature (T-F), Fermi wavenumber (K-F), Fermi wavelength ((F)) as well as the carrier concentration (N/V) values were calculated and discussed as a function of the nanoparticles content.