Effect of sintering and annealing temperatures on the critical temperature and electrical resistivity of Bi2Ba2Ca2Cu3O10+δ

الملخص EN

Samples of the high temperature superconducting system, Bi2Ba2Ca2Cu3O10+δ, were prepared by using the solid state reaction method with different sintering temperatures of 810, 830, 850, 870 and 890 oC.

The electrical resistivity measurements exhibited that the sintering and annealing conditions have major effects on the critical temperature of the superconducting compound.

The sample prepared at 850 oC has a critical temperature Tc ≈110 K, meanwhile the sample prepared at 870 oC has a critical temperature ≈ 80 K.

However, the sample which was prepared at 890 oC showed semiconducting behavior with an activation energy of 6.40 meV.

The effect of annealing on the critical temperature has been investigated using the sample prepared at 850 oC.

The value of Tc at the annealing temperature of 400 oC rises from 110 K to 138 K with increasing the annealing time from 24 hrs to 72 hrs.

This increase might be due to the increase of oxygen content or to the intergrowth of a large number of Cu-O layers in the cell.