SrFe_(0.6)Cu_(0.3)Ti_(0.1)O_(3-δ)混合导体透氧材料的稳定性

Stability of SrFe_(0.6)Cu_(0.3)Ti_(0.1)O_(3-δ) Mixed Conducting Membrane Material

利用柠檬酸络合法制备了SrFe(Cu,Ti)O3-δ混合导体透氧材料。采用XRD、O2-TPD、H2-TPR、SEM等测试技术考察了材料的稳定性。结果表明,SrFe0.7Cu0.3O3-δ在低氧压下会发生相分解,产生SrCuO2杂相,而掺杂Ti后的SrFe0.6Cu0.3Ti0.1O3-δ在低氧压下保持单一的钙钛矿结构。H2-TPR和O2-TPD的测试表明,Ti4+的掺杂提高了材料的氧脱附起始温度和其它金属离子的还原温度。SrFe0.6Cu0.3Ti0.1O3-δ膜在透氧过程中,会有Cu2+和Sr2+从钙钛矿结构中析出,在原晶粒边界形成新的小晶粒,但这种轻微的组分偏析没有影响到材料的透氧量,此透氧膜在66 h的操作过程中显示了良好的稳定性。

SrFe（Cu,Ti）O3-δ mixed conducting membrane materials were synthesized by citric acid complexing method.The stabilities of the materials were studied by means of XRD,O2-TPD,H2-TPR and SEM.It was found that phase decomposition occurred in SrFe0.7Cu0.3O3-δ under a low oxygen partial pressure and a minor phase SrCuO2 was formed.The addition of Ti4＋ greatly enhanced the structure stability of the material,and SrFe0.6Cu0.3Ti0.1O3-δ maintained single-phased perovskite structure.H2-TPR and O2-TPD results showed that the addition of T^i4＋ increased the initial oxygen desorption temperature of the material,and the reduction temperature of the other metal ions.Slight phase decomposition was found on the He-side surface of SrFe0.6Cu0.3Ti0.1O3-δ membrane after oxygen permeating test and fresh small grains congregated at the boundary of the initial grains.SrFe0.6Cu0.3Ti0.1O3-δ exhibits a high stability during 66 h oxygen permeating process.