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Title: Crystal Structure Solution and High Temperature Thermal Expansions of NaZr2(PO4)3-type Materials
The NaZr2P3O12 family of materials have shown low and tailorable thermal expansion properties. In this study, SrZr4P6O24 (SrO 4ZrO2 3P2O5), CaZr4P6O24 (CaO 4ZrO2 3P2O5), MgZr4P6O24 (MgO 4ZrO2 3P2O5), NaTi2P3O12 [1 2(Na2O 4TiO2 3P2O5)], NaZr2P3O12 [1 2(Na2O 4ZrO2 3P2O5)], and related solid solutions were synthesized using the organic–inorganic steric entrapment method. The samples were characterized by in-situ high-temperature X-ray diffraction from 25 to 1500 C at the Advanced Photon Source and National Synchrotron Light Source II. The average linear thermal expansion of SrZr4P6O24 and CaZr4P6O24 was between  1  x 10 -6 per  °C and 6  x 10 -6 per  °C from 25 to 1500 °C. The crystal structures of the high-temperature polymorphs of CaZr4P6O24 and SrZr4P6O24 with R3c symmetry were solved by Fourier difference mapping and Rietveld refinement. This polymorph is present above  1250 °C. This work measured thermal expansion coefficients to 1500 °C for all samples and investigated the differences in thermal expansion mechanisms between polymorphs and between compositions.  more » « less
Award ID(s):
1838595
PAR ID:
10498209
Author(s) / Creator(s):
Editor(s):
Edited by O. V. Yakubovich, Moscow State University
Publisher / Repository:
https://zenodo.org/records/8121949 IUCr publisher
Date Published:
Journal Name:
Acta crystallographica Section B Structural science
Edition / Version:
Acta Crystallographica B
Volume:
B80
Issue:
in press
ISSN:
0108-7681
Page Range / eLocation ID:
1-14 in press
Subject(s) / Keyword(s):
NZP-type materials CaZr4(PO4)6 SrZr4(PO4)6 phase transformation thermal expansion structure solution Fourier difference map powder diffraction.
Format(s):
Medium: X Other: https://zenodo.org/records/8121949
Sponsoring Org:
National Science Foundation
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