Garrett Mahler , Charles Iyare Jr. , Carolina Avalos , Seongyoung Kong , Kirill Kovnir , Joya A. Cooley
{"title":"Tuning thermal expansion and phase transition temperature with Mg substitution in Zn2V2O7","authors":"Garrett Mahler , Charles Iyare Jr. , Carolina Avalos , Seongyoung Kong , Kirill Kovnir , Joya A. Cooley","doi":"10.1016/j.jssc.2025.125296","DOIUrl":null,"url":null,"abstract":"<div><div>The thermal expansion coefficient of a material exhibiting negative thermal expansion above 400 °C, Zn<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>V<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>7</mn></mrow></msub></math></span>, was tuned using Mg as a substituent on the Zn site. Samples <span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>0</mn><mo>,</mo><mn>0</mn><mo>.</mo><mn>1</mn><mo>,</mo><mn>0</mn><mo>.</mo><mn>2</mn></mrow></math></span> 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<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>V<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>O<span><math><msub><mrow></mrow><mrow><mn>7</mn></mrow></msub></math></span> transitions from the <span><math><mi>α</mi></math></span> phase (<span><math><mrow><mi>C</mi><mn>2</mn><mo>/</mo><mi>c</mi></mrow></math></span>) to the <span><math><mi>β</mi></math></span> phase (<span><math><mrow><mi>C</mi><mn>2</mn><mo>/</mo><mi>m</mi></mrow></math></span>) 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<sup>−1</sup> in <span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>0</mn></mrow></math></span> to –13.46 ppm K<sup>−1</sup> in <span><math><mrow><mi>x</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>3</mn></mrow></math></span>.</div></div>","PeriodicalId":378,"journal":{"name":"Journal of Solid State Chemistry","volume":"347 ","pages":"Article 125296"},"PeriodicalIF":3.2000,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Solid State Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022459625001197","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
The thermal expansion coefficient of a material exhibiting negative thermal expansion above 400 °C, ZnVO, was tuned using Mg as a substituent on the Zn site. Samples 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 ZnVO transitions from the phase () to the phase () 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 to –13.46 ppm K−1 in .
期刊介绍:
Covering major developments in the field of solid state chemistry and related areas such as ceramics and amorphous materials, the Journal of Solid State Chemistry features studies of chemical, structural, thermodynamic, electronic, magnetic, and optical properties and processes in solids.