Low temperature synthesis of CaZrO3 nanoceramics from CaCl2–NaCl molten eutectic salt

Document Type : Research Paper

Authors

1 Young Researchers and Elite Club, Zanjan Branch, Islamic Azad University, Zanjan, Iran

2 School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran

Abstract

CaZrO3 nanoceramics were successfully synthesized at 700 C using the molten salt method, and the effects of processing parameters, such as temperature, holding time, and amount of salt on the crystallization of CaZrO3 were investigated. CaCl2, Na2CO3, and nano-ZrO2 were used as starting materials. On heating, CaCl2–NaCl molten eutectic salt provided a liquid medium for the reaction of CaCO3 and ZrO2 to form CaZrO3. The results demonstrated that CaZrO3 started to form at about 600C and that, after the temperature was increased to 1,000C, the amounts of CaZrO3 in the resultant powders increased with a concomitant decrease in CaCO3and ZrO2 contents. After washing with hot distilled water, the samples heated for 3 h at 700C were single-phase CaZrO3 with 90–95 nm particle size. Furthermore, the synthesized CaZrO3 particles retained the size and morphology of the ZrO2 powders which indicated that a template mechanism dominated the formation of CaZrO3 by molten-salt method.

Keywords


[1]. G. Ro´g, M. Dudek, A. Kozlowska-Ro´g, M. Buc´ko, Calcium zirconate: preparation, properties and application to the solid oxide galvanic cells, J. Electrochimica Acta. 47 (2002) 4523- 4529.
[2]. T. Yu, C. H. Chen, X. F. Chen, W. Zhu, R. G. Krishnan, Fabrication and characterization of perovskite CaZrO3 oxide thin films, Ceram. Int. 30 (2004) 1279-1282. [3]. W.J. Lee, A. Wakahara, B.H. Kim, Decreasing of CaZrO3 sintering temperature with glass frit addition, Ceram. Int. 31 (2005) 521-524.
[4]. Z.S. Li, W.E. Lee, S. Zhang,Lowtemperature synthesis of CaZrO3 powder from molten Salts, J. Am. Ceram. Soc. 90 (2007) 364-368. [5]. Z. Song, Q. Li, D. Ma, J. Wen, F. Yuan, and S. Deng, Production Process for Electrically Fused Calcium Zirconate China patent.page 6 (2003).
[6]. C. Moure, L.D. Olmo, G.F. Arroyo, P. Duran, J. R. Jurado, C. Pascual, Sintering and Densification of Calcium Zirconate Powders Prepared by Coprecipitation, Science of Ceram. 12 (1984) 321-326. [7]. G. Pfaff, Wet Chemical Synthesis of the Calcium Zirconates CaZrO3 and CaZr4O9, Mater.Sci. 3 (2002) 59-67. [8]. F. Gonenli , A. C. Tas, Chemical Synthesis of Pure and Gd-Doped CaZrO3 Powders, J. Eur. Ceram. Soc. 19 (1999) 2563-2567. [9]. R. Ianos, P. Barvinschi, Solution combustions synthesisofcalciumzirconate, CaZrO3, powders, J. Solid State Chem. 183 (2010) 491-496. [10]. S. K. Manik, S. K. Pradhan,X-ray Microstructure Characterization of Ball-Milled Nanocrystalline Microwave Dielectric CaZrO3 by Rietveld Method J. Appl. Crystallogr. 38 (2004) 291-298. [11]. Z. Song, J. Ma, H. Sun, W. Wang, Y. Sun, L. Sun, Z. Liu, C. Gao, Synthesis of NiWO4 nano-particles in low temperature molten salt medium,Ceram. Int. 35 (2009) 2675-2678. [12]. X. Jiang, J. Ma, Y. Yao, Y. Sun, Z. Liu, Y. Ren, J. Liu, B. Lin, Low temperature synthesis of SrWO4 nano-particls by a molten salt method, Ceram. Int. 35(2009) 3525-3528. [13]. R. S. Roth, M. A. Clevinger, and D. McKenna, Phase Diagrams for Ceramists, Edited by Smith G. American Ceramic Society, (1984) 63-66. [14]. J. Kubaschewski, C.B. Alcock, Metallurgical Thermochemistry, 5th edition, Pergamon Press, Oxford, (1979). [15]. Z. Li, S. Zhang, W.E. Lee, Molten salt synthesis of LaAlO3 powder at low temperatures, J. Eur. Ceram. Soc. 27 (2007) 3201-3205. [16]. Z. Li, S. Zhang, W.E. Lee, Molten salt synthesis of zinc aluminate powder, J. Eur. Ceram. Soc. 27 (2007) 3407-3412. [17]. T.P. Boyarchuk, E.G. Khailova, V.L. Cherginets, Potentiometric Measurements in Molten Chlorides Solubilities of Metal Oxides in the Molten Eutectic Mixture CsCl–KCl–NaCl at 600oC, J. Electrochim Acta. 38 (1993) 1481-1485.
[18]. V.L. Cherginets, E.G. Khailova, On the Solubility of Bivalent Metal Oxides in Molten Alkaline Chlorides,J. Electrochim Acta. 39 (1994) 823-829.