Method for oxygenating oxide superconductive materials

A method of oxygenating an oxide superconductive material having an initial oxygen content, said method comprising the steps:

• (a) obtaining an oxide superconductive material, wherein said oxide superconductive material comprises a compound having a formula selected from the group consisting of YBa.sub.2 Cu.sub.3 O.sub.x and Y.sub.2 Ba.sub.4 Cu.sub.7 O.sub.x, said material having an initial oxygen content;
• and
• (b) placing said oxide superconductive material in contact with an oxygen-containing media having an oxygen chemical potential greater than that of pure oxygen at 1 atmosphere pressure and at 300 degrees C, said oxygen chemical potential being achieved by application of energy from a mechanical or chemical source, and raising the temperature of said oxide superconductive material to a temperature above about 400 degrees C, and maintaining said oxide superconductive material at said temperature and under said chemical potential of oxygen for sufficient time so as to oxygenate said oxide superconductive material to a level above said initial oxygen content, wherein said oxygenation occurs without substantial change in the ratio of non-oxygen cations and anions.