SYNTHESIS OF A 90 K Y2BA4CU7O15-X SUPERCONDUCTOR UNDER AMBIENT-PRESSURE BY TRIETHYLAMMONIUMOXALATE COPRECIPITATION

Abstract

A 90 K superconducting Y2Ba4Cu7O15-x (247) powder with fine and homogeneous grain size was prepared by oxalate/triethylamine co-precipitation of a stoichiometric amount of mixed cations of yttrium, barium and copper from their aqueous solution of nitrate salts. Characterization results of the 247 superconductor by X-ray diffraction, electrical resistivity and magnetization measurements are reported. The intragrain critical current density (J(c)) of the as-prepared 247 superconductor was derived from magnetic hysteresis to be 8.5 X 10(6) A/cm2 at 5 K and 1 T. This new route may have considerable potential in the large-scale preparation of Y2Ba4Cu7O15-x.