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

The (Bi1.6Pb0.4)Sr2Ca2Cu3O10ZnO (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, xi, and smaller than the penetration depth, lambda, 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 xi was more effective in enhancing J (c).