Preparation and Thermal Expansion of Calcium Iron Zirconium Phosphates with the NaZr2(PO4)3 Structure

• Published in: Inorganic materials 2018, Vol.54 (6), p.591-595
• Main Authors: Savinykh, D. O., Khainakov, S. A., Orlova, A. I., Garcia-Granda, S.
• Format: Article
• Language: English
• Subjects: Calcium zirconate; Chemistry; Chemistry and Materials Science; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Phosphates; Sol-gel processes; Solid solutions; Synthesis; Thermal expansion; X-ray diffraction; Zirconium
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168518060122

Ca 0.5(1 + x ) Zr 2– x Fe x (PO 4 ) 3 phosphates have been synthesized by a sol–gel process. The individual compounds and solid solutions obtained crystallize in the NaZr 2 (PO 4 ) 3 structure (trigonal symmetry, sp. gr. R 3 ¯ ). Using high-temperature X-ray diffraction, we have determined their thermal expansion parameters in the temperature range from 25 to 800°C. With increasing x , the magnitudes of their linear thermal expansion coefficients and thermal expansion anisotropy decrease. Most of the synthesized phosphates can be rated as low-thermal-expansion compounds and can be regarded as materials capable of withstanding thermal “stress.”