摘要
研究钴离子部分取代铜离子对YBa2 Cu3 O6+δ的氧非计量值δ和氧渗透率的影响 .对于钴替代的样品 ,氧非计量的绝对值变大 ,且其数值不再随温度和氧分压的变化发生显著变化 .YBa2 Cu2 CoO6+δ样品在中、高温具有可观的氧渗透率 .对于厚度为 1.2mm的致密YBa2 Cu2 CoO6+δ样品 ,在 85 0℃时 ,只要在样品两端施加较小的氧分压差(PO2 =2 1.2kPa、PO2 =10 1Pa) ,其氧渗透率即可达 5 7μmol/cm2 s,明显高于YBa2 Cu3 O6+δ的氧渗透率 (31μmol/cm2s) .YBa2 Cu2
The effects of substitution of Cu by Co in YBa 2Cu 3O 6+δ on the oxygen nonstoichiometry and permeability were investigated. The oxygen nonstochiometry δ 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 μmol/cm 2s was observed at 850℃ from YBa 2Cu 2CoO 6+δ disk-shaped dense sample of thickness 1.2 mm with one side exposed to air (P O 2=21.2 kPa) and the other side to flowing helium (P O 2=101 Pa), but only 31 μmol/cm 2s was measured for YBa 2Cu 3O 6+δ. The improved oxygen permeabilty in YBa 2Cu 2CoO 6+δ was attributed to the even distribution of oxygen ions and oxygen vacancacies in the basal plane.
基金
ProjectsupportedbytheNationalNaturalScienceFoundationofChina (5 0 2 2 5 2 0 8)
