Premium
Effect of pH on synthesis and properties of perovskite oxide via a citrate process
Author(s) -
Wu Zhentao,
Zhou Wei,
Jin Wanqin,
Xu Nanping
Publication year - 2006
Publication title -
aiche journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.958
H-Index - 167
eISSN - 1547-5905
pISSN - 0001-1541
DOI - 10.1002/aic.10664
Subject(s) - crystallinity , oxide , oxygen permeability , oxygen , perovskite (structure) , chemistry , inorganic chemistry , chemical engineering , membrane , materials science , crystallography , organic chemistry , biochemistry , engineering
A series of La 0.6 Sr 0.4 Co 0.4 Fe 0.6 O 3‐δ (LSCF) perovskite‐type oxides were synthesized using a modified citrate process under various pH conditions (pH =1, 3, 5, 7, and 9, respectively). The effect of pH on the chelate process, crystal development, morphology, and oxygen permeability of LSCF oxides were investigated. FT‐IR analysis showed that the chelate processes for pH = 1 and 3 were different from those for pH = 5, 7, and 9. XRD and SEM observations revealed that the crystal formation and morphology of LSCF oxides were dependent on the precursors with different pH conditions. The LSCF membranes derived from the precursors with lower pH values (pH = 1 and 3) exhibited larger apparent activation energy for oxygen permeation than the other samples (pH = 5, 7, and 9) in the range of 1073‐1123K. This study indicated that properties such as crystallinity and oxygen permeability of LSCF oxide could be tailored by controlling the pH values in the synthesis process. © 2005 American Institute of Chemical Engineers AIChE J, 2006