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.Sr4Fe4Co2O13±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±δoxides 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±δwas 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 SrFe6-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±δwas treated in pure oxygen environ-ment,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.
参考文献
| [1] | Gellings P J,Bouwmeester H J M.Catal.Today,1992,12: 1-105. |
| [2] | Steele B C H.Solid.State Ionics,1995,76: 321-329. |
| [3] | 邵宗平,熊国兴.化学进展,1999,11 (1): 30-40. |
| [4] | Itoh N,Sanchez C M A,Xu W C,et al.J.Membr.Sci.,1993,77: 245-253. |
| [5] | Zeng Y,Lin Y S,Swartz S L.J.Membr.Sci.,1998,150: 87-98. |
| [6] | Tsai C Y,Ma Y H,Moser W R,et al.Chem.Eng.Commun.,1995,134: 107-132. |
| [7] | Balachandran U,Dusek J T,Mieville R L,et al.Appl.Catal.A: Gen.,1995,133: 19-29. |
| [8] | Foster E P,Tijm P J A,Bennett D L.Stud.Surf.Sci.Catal.,1998,119: 867-874. |
| [9] | Balachandran U,Kleefisch M S,Kobylinski T P,et al.U S Patent,1998.5,723,074. |
| [10] | Balachandran U,Kleefisch M S,Kobylinski T P,et al.International Patent,1994.WO 94/24065. |
| [11] | Ma B,Balachandran U.Mater.Res.Bull.,1998,33: 223-236. |
| [12] | Guggilla S,Manthiram A.J.Electrochem.Soc.,1997,144: L120-L122. |
| [13] | Fjellvag H,Hauback B C,Bredesen R.J.Mater.Chem.,1997,7 (12): 2415-2419. |
| [14] | Kim S,Yang Y L,Christoffersen R,et al.Solid.State.Ionics,1998,109: 187-196. |
| [15] | Balachandran U,Ma B,Maiya P S,et al.Solid.State.Ionics,1998,108: 363-370. |
| [16] | 邵宗平,盛世善,熊国兴,等.功能材料,1998,28: 1190-1191. |
| [17] | Shao Z P,Xiong G X,Sheng S S,et al.Stud.Surf.Sci.Catal.,1998,108: 431-438. |
| [18] | 邵宗平,熊国兴,杨维慎(SHAO Zong-Ping,et al).无机材料学报(Journal of Inorganic Materials),2000,15 (1): 124-130. |
| [19] | Ma B,Hodges J P,Jorgensen J D,et al.J.Solid.State.Chem.,1998,141: 576-586. |
| [20] | Kim S,Yang Y L,Christoffersen R,et al.Solid.State.Ionics.,1997,104: 57-65. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%