Phase transitions of LiAlO2 at high pressure and high temperature

✍ Scribed by Li Lei; Duanwei He; Yongtao Zou; Wei Zhang; Zhao Wang; Ming Jiang; Maolu Du

• Publisher: Elsevier Science
• Year: 2008
• Tongue: English
• Weight: 343 KB
• Volume: 181
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2008.04.006

✦ Synopsis

This work presents a comprehensive study on phase transitions in LiAlO 2 system at high pressures and temperatures (0.5-5.0 GPa and 300-1873 K, respectively), as well as the phase stability for polymeric phases of LiAlO 2 in the studied P-T space by X-ray diffraction (XRD). Besides the previously described polymorphic hexagonal a-phase, orthorhombic b-phase and tetragonal d-phase, a possible new phase of LiAlO 2 was observed after the tetragonal g-LiAlO 2 sample was treated at 5.0 GPa and 389 K. The stable regimes of these high-pressure phases were defined through the observation of coexistence points of the polymeric phases. Our results revealed that LiAlO 2 could experience structural phase transitions from g-LiAlO 2 to its polymorphs at lower pressures and temperatures compared to the reported results. Hexagonal a-LiAlO 2 with highly (003) preferential orientation was prepared at 5.0 GPa and 1873 K.