Solubility limit of Zn²⁺ in low thermal expansion ZrMgMo<inf>3</inf>O<inf>12</inf> and its influence on phase transition temperature

Abstract:

Low thermal expansion in ABM3O12 phases, such as ZrMgMo3O12, have drawn significant attention due to their potencial applications as advanced ceramics with remarkable thermal shock resistance. Herein, we explored Zn2+ additions into ZrMgMo3O12 due to its potential to tune the coefficient of thermal expansion to even lower values. The influence of the solubility limit of Zn2+ in ZrMg1-xZnxMo3O12 on the temperature of the phase transition from the monoclinic to the orthrombic phase (x = 0.10; 0.30; 0.35 and 0.40) was thoroughly studied. X-ray powder diffraction (XRPD) confirmed the stability of the orthorhombic (Pna21) phase over a wide temperature range, for compositions up to x = 0.35, while for x = 0.40 the solubility limit of Zn2+ was exceeded and monoclinic ZnMoO4 appeared as a secondary phase. As the Zn2+ content increases, the transition temperature is shifted to higher temperatures, as demonstrated by XRPD and differential scanning calorimetry (DSC). The onset of the transition temperature for x = 0.10, 0.30 and 0.35 was 181, 240 and 253 K, respectively. All these values are well below room temperature, which is of paramount importance from a technological perspective. Thermogravimetric analysis shows that the as-synthesized phases are not hygroscopic.

Año de publicación:

2020

Keywords:

• Thermal shock resistance
• negative thermal expansion
• In situ XRPD
• A M O 2 3 12

Fuente:

scopus

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