用湿化学法合成了Ｓｒ４ＣｏｘＦｅ６－ｘＯ１３±δ系列混合导体氧化物，对其相结构与透氧性能进行了研究．钴离子的引入导致材料中钙钛矿型杂相的出现，Ｘ＝２．０时材料中还产生了ＣｏＯ杂相，ｘ＝２．６时材料呈现钙钛矿型结构．Ｓｒ４Ｆｅ４Ｃｏ２Ｏ１３±δ的相结构还与焙烧温度及环境气氛中的氧浓度密切相关．随着氧浓度的降低，材料从纯相Ｓｒ４Ｆｅ６Ｏ１３结构（纯氧气气氛下）转变为Ｓｒ４Ｆｅ６Ｏ１３结构、钙钛矿型结构和ＣｏＯ共存（空气气氛下），直至转变为针镍矿结构、 Ｓｒ４Ｆｅ６Ｏ１３结构和 ＣｏＯ共存． Ｓｒ４Ｆｅ６Ｃｏ１３±δ导体膜在ａｉｒ／Ｈｅ氧浓差梯度下的透氧量为 １．５×１０-８ｍｏｌ／ｃｍ２·ｓ（８５０℃），在６５０～８５０℃范围内透氧活化能为７０ｋＪ／ｍｏｌ．
Mixed-conducting Sr4CoxFe6-xO13±δ oxides were synthesized by pyrolysis of cellulose-citric-metal salt compound.
Their crystal structures were investigated, and oxygen permeability of Sr4Co2Fe4O13±δ was also studied by a GC method. The
introduction of cobalt in Sr4Fe6O13 led to the occurrence of perovskite phase in the Sr4Fe6O13 bulk even at low doping
content of cobalt (x=0.5), some minor CoO phase was also observed when x=2.0, and the material mainly demonstrated perovskite structure when
x=2.6. The phase structure of Sr4CoxFe6-xO13±δ was found to be closely related with the calcined temperature and the
oxygen concentration in the ambient atmosphere during calcination or retreatment at high temperature. The air-synthesized sample had the
intergrowth phase Sr4Fe6-xCoxO13±δ and the perovskite phase Sr(Fe, Co)O3-δ coexisted along with CoO impurity. The
N2-annealed sample coexisted of Sr4Fe6O13 phase, brownmillerite phase and minor CoO impuirty. When Sr4Co2Fe4O13±δ
was treated in pure oxygen environment, the sample changed to single phase (Sr4Fe6O13 type phase). The oxygen permeability of
Sr4Co2Fe4O13±δ membrane had a value close to 1.5×10-8mol/cm2·s at 1123K. From 923K to 1223K, the activation energy for oxygen transportation was about 70kJ/mol.
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