Materials having a zero resistance transition temperature above 200 K and method for maintaining the zero resistance property

摘要

This invention is directed to a method for making multiphase copper oxide based materials which have a phase having a zero resistance transition temperature above about 200K. The method comprises subjecting a copper oxide based material precursor to an oxygenation in an atmosphere comprising more than about 20% oxygen by volume at a temperature less than about 200° C. for a time sufficient to form the material. The invention also is directed to maintaining the properties of a copper oxide based material having a zero resistance transition temperature above 150K.