Synthesis and characterization of PbO–CdO nanocomposite and its effect on (Bi,Pb)-2223 superconductor

Abstract

A PbO–CdO nanocomposite-added Bi1.6Pb0.4Sr2Ca2Cu3O10 ((Bi,Pb)-2223) superconductor has been prepared. The effect of the PbO–CdO nanocomposite addition on the transport critical current density (Jc) of (Bi,Pb)-2223 superconductor was investigated. The transition temperature (Tc−onset), zero electrical resistance temperature (Tc−R=0), and Jc of the samples were measured by the four-probe method. Phase formation, structure, and microstructure of samples were investigated. The distribution of nanoparticle size was determined. The results indicated that the PbO–CdO-added samples showed larger grain size and an increased volume fraction of high-Tc phase (Bi-2223) compared to the non-added sample. A slight increase in Tc−R=0 of x = 0.15 wt% was observed. Jc of the PbO–CdO nanocomposite-added samples was significantly higher than for the non-added sample. That could be explained by the possibility that the PbO–CdO nanocomposite acts as an effective flux pinning center in (Bi,Pb)-2223. At 77 K, Jc of x = 0.15 wt% added sample was more than 20 times larger than Jc of the non-added sample (x = 0 wt%). A combined effect of enhanced flux pinning, increased fraction of high-Tc phase and improved grain size, which led to increase in the Jc of added samples, is discussed.