Abstract
Effects of the Li-addition to the Bi-2212 phase on the formation process and the superconductive properties were studied for the samples with the nominal compositions of Bi:Sr:Ca:Cu:Li=2:1.5 :1.5:2:x(x=0 to 0.6). The samples were heated at 560-860°C for 1 to 48h in air. Monophasic Bi-2212 samples was obtained for x=0.2 to 0.6 by heating above 730°C, which was approximately 100°C lower than that of the sample with x=0.A new compound containing Li element was formed in the temperature range between 700 and 720°C, which remarkably promoted the formation of the Bi-2212 phase. The lattice parameter c of the Bi-2212 phase increase with increasing Li content. The temperature dependence of magnetic susceptibility showed that Tc rose up to 90K for the sample with x=0.4 heated at 750°C for 12h.
