Autor: | H. Van den Rul, M. K. Van Bael, L.C. Van Poucke, K. Van Werde, D. Nelis, G. Vanhoyland, Jules Mullens, D. Mondelaers |
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Rok vydání: | 2003 |
Předmět: |
Materials science
Aqueous solution Metal ions in aqueous solution Inorganic chemistry Chemical modification chemistry.chemical_element General Chemistry Quaternary compound Condensed Matter Physics Oxalate Electronic Optical and Magnetic Materials Bismuth Biomaterials chemistry.chemical_compound chemistry Materials Chemistry Ceramics and Composites Strontium oxide Sol-gel |
Zdroj: | Journal of Sol-Gel Science and Technology. 26:1125-1129 |
ISSN: | 0928-0707 |
DOI: | 10.1023/a:1020771126807 |
Popis: | The synthesis of multimetal oxides containing pentavalent elements like Nb and Ta out of an aqueous solution is very complicated due to the extremely high sensitivity of these metals towards hydrolysis. Moreover the only water-soluble starting compound is the oxalate which is not very suited for gel formation. Nevertheless, from Nb-oxalate it is possible to prepare a water-soluble Nb(V)-precursor by chemical modification. The synthesized precursor remains stable in the pH-range needed for gel formation. This Nb(V)-precursor is used for the synthesis of the ferroelectric material SrBi2Nb2O9 (SBN). An aqueous acetate-citrate solution-gel precursor for SBN was prepared. The chemical homogeneity of this precursor was investigated by means of TEM-experiments. All metal ions were found to be homogeneously dispersed in the precursor gel at least down to 10 nm. The SBN phase formation is followed by means of X-ray Diffraction. It has been shown that the perovskite phase already forms at 550°C. |
Databáze: | OpenAIRE |
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