Investigation of zirconium phosphate Zr{sub 3}(PO{sub 4}){sub 4} during heating

• Published in: Crystallography reports 2009-05, Vol.54 (3)
• Main Authors: Orlova, A. I., Samoilov, S. G., Kazantsev, G. N., Volgutov, V. Yu, Bykov, D. M., Golubev, A. V., Borovikova, E. Yu
• Format: Article
• Language: English
• Subjects: CALORIMETRY; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; COOLING; CRYSTALLOGRAPHY; EXPANSION; HEATING; INFRARED SPECTRA; PHASE TRANSFORMATIONS; SODIUM PHOSPHATES; SOL-GEL PROCESS; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TRIGONAL LATTICES; X-RAY DIFFRACTION; ZIRCONIUM PHOSPHATES
• ISSN: 1063-7745; 1562-689X
• DOI: 10.1134/S1063774509030109

Zirconium phosphate Zr{sub 3}(PO{sub 4}){sub 4} has been synthesized by the sol-gel technique and investigated using X-ray powder diffraction, IR spectroscopy, and differential scanning calorimetry. It has been established that the symmetry of the unit cell, R3-barc, which is characteristic of the NaZr{sub 2}(PO{sub 4}){sub 3} (NZP) family, is lowered to P3-barc. The behavior of the zirconium phosphate during heating has been examined using high-temperature X-ray diffraction at temperatures ranging from 25 to 575 deg. C. It has been revealed that the structure of the zirconium phosphate is hardly subjected to expansion due to heating in the temperature ranges 25-125 deg. C ({alpha}{sub a} < 1 x 10{sup -6} K{sup -1}, {alpha}{sub c} < 1 x 10{sup -6} K{sup -1}, {Delta}{alpha} < 1 x 10{sup -6} K{sup -1}) and 325-575{sup o}C ({alpha}{sub a} = -1.4 x 10{sup -6} K{sup -1}, {alpha}{sub c} < 1 x 10{sup -6} K{sup -1}, {Delta}{alpha} < -2.4 x 10{sup -6} K{sup -1}). In the temperature range 125-325{sup o}C, the synthesized compound undergoes a second-order phase transition (upon heating), which is accompanied by the contraction of the structure along all crystallographic directions. Upon cooling in the range from 75 to 25 deg. C, the phase transition is accompanied by the expansion of the structure.