Towards the investigation of ternary compound in the Ti-Al-Zr-O system: Effect of oxygen fugacity on phase formation

The Ti-Al-Zr-O system has received significant attention as it hosts a variety of phases of industrial interest. In this paper, new experiments on the Ti-Al-Zr-O system aimed at clarifying phase formation depending on the redox conditions with special attention to the formation of ternary compounds and their results have been reported. For the first time a monophase AlTi₂O₅ sample with a ratio of titanium oxides TiO₂:Ti₂O₃ = 2:1 was obtained and characterized. Single-crystal X-ray diffraction analysis of β-(Zr_xTi_1-x)₂O₄ crystals was carried out. The synthesis of the ternary Ti-Al-Zr compound was performed in an evacuated quartz ampoule and accompanied by the extraction of silicon from the ampoule. The compound has pyrochlore-type cubic structure A₂ ⁴⁺B₂ ³⁺O₇ (Fd-3m) and the composition close to (Ti⁴⁺ _1,47(2)Zr_0.41(2)Si_0.12(1))₂(Al_1.15(4)Ti³⁺ _0.85(4))₂O₇. We believe that our study is a starting point for future research as it provides first experimental data on the ternary compound in the Ti-Al-Zr-O system.