Oxygen Nonstoichiometry And Permeability Of Co-Substituted Yba2cu3o6+Delta

The effects of substitution of Cu by Co in YBa2Cu3O6+delta on the oxygen nonstoichiometry and permeability were investigated. The oxygen nonstochiometry delta increased as a result of Co substitution, and its values did not change very much with the changing temperature and oxygen partial pressure. An oxygen permeation flux of 57 mumol/cm(2)s was observed at 850degreesC from YBa2Cu2CoO6+delta disk-shaped dense sample of thickness 1.2 mm with one side exposed to air (P-0 2=21.2 kPa) and the other side to flowing helium (P-0 2=101 Pa), but only 31 mumol/cm(2)s was measured for YBa2Cu3O6+delta. The improved oxygen permeabilty in YBa2Cu2CoO6+delta was attributed to the even distribution of oxygen ions and oxygen vacancacies in the basal plane.