EFFECT OF NANOSIZE MgO PARTICLES ADDITION ON FORMATION AND SUPERCONDUCTIVITY OF Tl0.9Bi0.1Sr1.95Ta0.05Ca0.9Y0.1Cu2O7- CERAMICS

Abstract

In this paper, nanosize MgO particles were added to Tl_0.9Bi_0.1Sr_1.95Ta_0.05Ca_0.9Y_0.1Cu₂O_7-d superconductor in various weight fraction between 0 wt.% to 0.8 wt.% before sintering using the conventional solid state synthesis method. The phase formation and the microstructure of the samples were studied by XRD and SEM, respectively. The highest critical temperature T_{c zero} of 80 K was observed at 0.2 wt.% MgO and T_c was gradually suppressed for higher MgO additions. The effect of the MgO addition on J_c revealed maximum J_c at 0.2 wt.% MgO addition. SEM investigations revealed no difference in microstructure for the pure sample and the MgO added samples. The results showed that a small amount of MgO addition (0.2 wt.%) in Tl-1212 enhanced J_c and this is suggested as due to increased flux pinning in the sample due to the MgO addition.