Tuning thermal expansion and phase transition temperature with Mg substitution in Zn 2 V 2 O 7
Year: 2025
Type: article
Abstract: The thermal expansion coefficient of a material exhibiting negative thermal expansion above 400 °C, Zn 2 V 2 O 7 , was tuned using Mg as a substituent on the Zn site. Samples x = 0 . 0 , 0 . 1 , 0 . 2 and 0.3 were prepared using high-temperature ceramic methods. Changes to the structure and properties with Mg substitution were analyzed using Rietveld refinement of ambient and variable-temperature X-ray diffraction data (VTXRD) using synchrotron radiation. The parent structure Zn 2 V 2 O 7 transitions from the α phase ( C 2 / c ) to the β phase ( C 2 / m ) near 650 °C, and Mg substitution lowers the temperature of this transition as corroborated by differential scanning calorimetry measurements. Mg substitution allows the volume thermal expansion coefficient to be tuned from –19.80 ppm K −1 in x = 0 . 0 to –13.46 ppm K −1 in x = 0 . 3 . • Mg-substituted Zn 2 V 2 O 7 was prepared by solid state synthesis. • Mg-substitution lowered temperature of α to β phase transition. • Increasing Mg content resulted in decreased magnitude of negative thermal expansion coefficient.
Source: Journal of Solid State Chemistry
Authors: Garrett Mahler, Charles Iyare, Carolina Avalos, Seongyoung Kong, Kirill Kovnir, Joya A. Cooley
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $3,540
OpenAlex ID: W4408288292