A Novel Tantalic Acid‐Based Polymerizable Complex Route to LiTaO3 Using Neither Alkoxides nor Chlorides of Tantalum.
A Novel Tantalic Acid‐Based Polymerizable Complex Route to LiTaO3 Using Neither Alkoxides nor Chlorides of Tantalum.
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DOI:
10.1002/chin.200001024
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发表时间:
2000-01
期刊:
影响因子:
--
通讯作者:
Judit Szanics;M. Kakihana
中科院分区:
文献类型:
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作者:
Judit Szanics;M. Kakihana
A novel tantalic acid-based polymerizable complex (PC) route to LiTaO3was developed that uses neither alkoxides nor chlorides of Ta. Moisture-insensitive Ta2O5was chosen as a starting source of Ta, and it was converted to a Ta−oxalate solution by means of the classic KHSO4−oxalic acid method of Schoeller. Tantalic acid precipitated upon addition of ammonia solution to the Ta−oxalate solution. The freshly precipitated tantalic acid was soluble in a hot oxalic acid aqueous solution, and it was quite stable against hydrolysis. This water-resistant Ta precursor mixed with citric acid (CA), ethylene glycol (EG), and Li2CO3was polymerized at 130 °C to produce a yellowish transparent polyester-type resin without undergoing precipitation, which after decomposition on heating at 350 °C was used as a powder precursor for LiTaO3. Phase-pure LiTaO3in powder form was successfully synthesized at a reduced temperature (500 °C). The final LiTaO3powder calcined at 500−700 °C had a considerably large surface area in the range of 22−37 m2/g when compared with 1.4 m2/g for the conventional solid-state reaction powder of the same compound.