Superconductivity above 100 K by Pr substitution in the two-copper-layer Bi-Pb-Sr-Ca-Cu-O system

Abstract
The effect of Pr substitution on superconducting and transport properties has been studied in the Bi-Pb-Sr-Ca-Cu-O system. We obtain samples with structure similar to the 80-K phase for Tc(R=0) up to 102 K. In particular, the highest Tc (102 K) is obtained with the nominal composition Bi1.7 Pb0.3 Sr1.8 Pr0.2 Ca2 Cu3 O10+y, showing an 80-K single phase. We believe that the variation of Tc is determined by changes in the hole density in the Cu-O2 planes due to the substitution of Pr into Sr sites.