钙钛矿型Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ)透氧膜材料的制备及其透氧性能的研究  

Preparation and Oxygen Permeability of Ba_(0.5)Sr_(0.5)Co_(0.8)Fe_(0.2)O_(3-δ) Perovskite-type Oxygen Permeation Membranes

作　　者：李培培[1] 程继贵[1] 李世松[1] 孙文周[1] 张旭晨[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,合肥230009

出　　处：《人工晶体学报》2015年第5期1183-1189,共7页Journal of Synthetic Crystals

基　　金：中航工业产学研合作创新工程项目(20120034)

摘　　要：通过甘氨酸硝酸盐法（GNP）合成了钙钛矿型Ba0.5Sr0.5Co0.8Fe0.2O3-δ（BSCF）复合氧化物粉体。经压制、烧结后,得到了BSCF烧结体试样,还通过硝酸溶液浸蚀处理对烧结体试样进行了表面浸蚀处理。采用X射线衍射仪（XRD）对煅烧后的粉体进行了相成分分析;采用扫描电子显微镜（SEM）及能谱仪（EDS）对烧结体和表面浸蚀后烧结体样品的微观组织和成分进行了表征;对烧结体的致密度、电导率进行了测试分析,并在自制的氧渗透装置上测定了BSCF钙钛矿膜的透氧量,分析了温度和不同氧分压差等对膜透氧性能的影响。实验结果表明,甘氨酸-硝酸盐法所制备的前驱体粉末在900℃煅烧3 h后可获得具有单一钙钛矿结构的BSCF粉体,1100℃煅烧的BSCF烧结体的电导率在600℃时最大达到38.15 S·cm-1。其透氧量随着温度和氧分压差的升高而增大,且硝酸表面浸蚀处理后,BSCF膜片的透氧性能有明显提高,透氧速率提高1.6~4.5倍。850℃,20%O2-80%N2混合气体/He条件下,浸蚀后的透氧膜片的透氧量达到2.36 m L/cm2·min,而未浸蚀透氧膜片的透氧量仅为1.36 m L/cm2·min。Ba0. 5Sr0. 5Co0. 8Fe0. 2O3- δ（ BSCF） powders were synthesized by a glycine-nitrate process. BSCF membranes were prepared by pressing and sintering the BSCF powders. The surface erosion of the membranes was carried out by using nitric acid. Phase structure of the synthesized powders was characterized by X-ray diffraction（ XRD） analysis. Microstructure and elements analysis of sintered the BSCF and modified the BSCF samples were characterized by scanning electron microscopy（ SEM） and energy dispersive spectrometer（ EDS）. Density and electrical conductivity of the sintered BSCF samples were measured. And the oxygen permeability of the membranes were determined by self-built oxygen permeability device. Effects of temperature and oxygen partial pressure on the oxygen permeability of the BSCF were also investigated. The results show that BSCF with a single perovskite structure can be obtained by calcining the precursors at 900 ℃ for 3 h. The BSCF samples sintered at 1100 ℃ have thehighest electrical conductivity of 38. 15 S ·cm- 1at 600 ℃. The oxygen permeability of BSCF samples increases with increasing test temperature and oxygen partial pressure. It is also found that surface nitric etching can improve surface oxygen exchange reaction and increase the oxygen fluxes up to 1. 6-4. 5times. At 850 ℃ under 20% O2-80% N2 mixer / He,the oxygen permeability of the modified membrane reaches 2. 36 m L / cm2·min,while the unmodified samples have a value of about 1. 36 m L/cm2·min.

关 键 词：甘氨酸-硝酸盐法 Ba0.5Sr0.5Co0.8Fe0.2O3-δ 电导率 表面浸蚀 透氧性能 

分 类 号：G312[文化科学] TB34[一般工业技术—材料科学与工程]