Crystal growth and characterization of the superconducting phase in the BiSrCuO system

Crystal growth was investigated in the system BiSrCuO. Layered bismuth cuprates with formulas close to (Bi, Sr)4CuOx or (Bi, Sr)5Cu2Ox and a typical micaceous, lath-like habit were grown by slow cooling from a wide range of compositions partially or totally melted in the temperature range 890-1000°C. Only (Bi, Sr)4CuOx crystals with 0.8<Sr/Bi<0.9 were superconducting, with Tc9-10 K. In Sr-rich melts, platy crystals of orthorhombic SrCuO2 and SrCu1.7Ox were obtained. BiSrCuO melts react with platinum below ca. 1000°C, leading to the formation of Sr4PtO6 crystals. © 1988.