The thermal behavior of some polymeric precursors used in CaAl12O19 synthesis
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CaAl12O19 was synthesised using three different precursors: (a) a polyesteric type precursor resulted from the traditional Pechini method; (b) a polyesteric type precursor resulted from the reaction between citric acid and calcium and aluminum nitrates; and (c) a polymeric type precursor resulted from the reaction between acrylic acid and calcium an aluminum nitrates. The thermal behavior of the three precursors used in the CaAl12O19 synthesis was monitored to underline the thermal effects associated to the CaAl12O19 formation. Thermal analyses performed on precursors do not reveal clear differences regarding the thermal effects assigned to calcium aluminates formation, at temperatures over 800 °C. In contrast, thermal analysis of samples pre-fired at 200 °C, and especially at 600 °C, show clear differences between samples obtained in different ways. It is noted that in samples obtained from acrylic acid and nitrates, and citric acid and nitrates, CA6 is practically single phase after calcination at 1,200 °C. However, in the sample obtained from citric acid, ethylene glycol, and nitrates, calcined at 1,200 °C, CA6 is present along with CA2 and α-Al2O3.
KeywordsCalcium aluminates Polymeric precursor method Thermal analysis
This work was partially supported by the strategic Grant POSDRU/88/1.5/S/50783, Project ID50783 (2009), co-financed by the European Social Fund—Investing in People, within the Sectoral Operational Programme Human Resources Development 2007–2013.
- 1.Ianoş R, Lazău I, Păcurariu C, Barvinschi P. Peculiarities of CaO·6Al2O3 formation by using low-temperature combustion synthesis. Eur J Inorg Chem. 2008;6:925–30.Google Scholar
- 4.Singh VK, Sharma KK. Low-temperature synthesis of calcium hexa-aluminate. J Am Ceram Soc. 2002;84(4):769–72.Google Scholar
- 14.Pan YX, Liu GK. Influence of Mg2+ on luminescence efficiency and charge compensating mechanism in phosphor CaAl12O19:Mn4+. J Lumin. 2010. doi: 10.1016/j.jlumi.2010.11.014.