Synthesis of YBa2Cu3O7−x from a soluble Y-Ba-Cu precursor

Abstract

The synthesis of the superconducting YBa₂Cu₃O_7−x from a soluble, molecular precursor with the composition Cu₃O₃Ba₂Y(meOEt)₇ (meOEt is 2‐methoxyethoxide) is described. The precursor was synthesized from the reaction of a soluble copper (II) oxide polymer with alkoxides of barium and yttrium. Pyrolysis and oxidation of the precursor resulted in the formation of oriented sheets of the orthorhombic YBa₂Cu₃O_7−x phase. The orientation in the bulk YBa₂Cu₃O_7−x is believed to result from the presence of linear Cu‐O‐Cu‐O chains in the precursor. Bulk YBa₂Cu₃O_7−x, prepared from the precursor, had an onset transition temperature of 92.5 K and zero resistance at 89.5 K.