Abstract
The effect of nano-sized CoFe2O4 particles (10 nm in diameter) addition on the structure and the normal state transport properties of polycrystalline Bi-based superconductors were systematically studied. The additional amount, x wt.%, of CoFe2O4 in this case varied from 0.0 to 1 wt.% of the total mass of the sample. Phase analysis by X-ray diffraction (XRD) and Electrical resistance as a function of temperature, (T) were carried out. Nano-sized particles addition modifies the electrical behavior of the normal state with increasing the CoFe2O4 concentration. The bipolaron model can explain properly the normal state resistivity of the samples.