Effects of nanosized Bi₂O₃ addition on the superconducting properties of Bi_1.6Pb_0.4Sr₂Ca₂Cu₃O₁₀

摘要

The effects of nanosized Bi 2 O 3 (150 nm) addition on Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 3 O10((Bi,Pb)-2223)superconductor have been investigated. Samples with nominal starting composition (Bi,Pb)-2223)(Bi 2 O 3 ) x with x = 0-0.15 wt.% were prepared using the co-precipitation method. The structureand microstructure were examined by using powder X-ray diffraction (XRD) method and scanningelectron microscopy (SEM), respectively. The onset-temperature (T c-onset ), zero-resistance-temperature(T c-zero ), and transport critical current density (J c ) were determined by using the four-probe technique.The XRD patterns confirmed the presence of Bi,Pb-2223 phase. J c of all Bi 2 O 3 added samples werehigher than the non-added sample. The highest J c , T c-zero and hole concentration (p) was observed inthe x = 0.01 sample. At 77 K, J c of x = 0.01 wt. % was about 42 times higher than the non-addedsample. This could be due to the enhanced flux pinning as the size of Bi 2 O 3 was between the coherencelength and penetration depth of (Bi,Pb)-2223.