Enhanced Electrical Transport Properties of Nano NiFe2O4-added (Bi1.6Pb0.4)Sr2Ca2Cu3O10 Superconductor

The effect of nanometer sized NiFe2O4 (∼15 nm) addition in Bi1.6Pb0.4Sr2Ca2Cu3O10 (Bi2223) superconductor was studied. The (Bi1.6Pb0.4)Sr2Ca2Cu3O10 superconductor was prepared through the co-precipitation method and 0.01 wt% to 0.05 wt% of nano NiFe2O4 was added. The critical temperature (Tc), critical current density (Jc), phase formation and microstructure were investigated. All samples showed a major Bi2223 phase with (Bi,Pb)2Sr2CaCu2O8 (Bi2212) as the minor phase. The sample with 0.01 wt% nano NiFe2O4 showed the highest Tc and Jc: of more than 3 orders of magnitude higher than the non-added sample at 77 K. A further nano NiFe2O4 addition (>0.01 wt%) leads to degradation of Tc and Jc. These results indicate that addition of an optimum amount of NiFe2O4 nanoparticles can effectively enhance the transport critical current density in this system.