Transport current density of (Bi1.6Pb0.4)Sr2Ca2Cu3O10 superconductor added with different nano-sized ZnO

The (Bi 1.6 Pb 0.4 )Sr 2 Ca 2 Cu 3 O 10 ZnO x ( x =0–0.05 wt%) superconductor with addition of ZnO with average particle size 6 nm and 30 nm was prepared using the co-precipitation method. The ZnO particle size was larger than the coherence length, ξ , and smaller than the penetration depth, λ , of the superconductor. The microstructure, transition temperature ( T c ) and transport critical current density ( J c ) were studied. SEM micrographs showed a homogeneous distribution of ZnO nanoparticles throughout the samples. J c of all the ZnO added samples were higher than the non-ZnO added sample. The maximal J c and T c were observed when x =0.02 wt% for both series. J c (77 K) of the 6-nm ZnO added sample was 46 times larger than the non-ZnO added sample. The 6-nm ZnO added sample also showed higher J c compared to the 30-nm ZnO added sample. ZnO with size closer to ξ was more effective in enhancing J c .