Nanocrystalline AZrTi₂O₇ (A = Mg, Ca, Sr and Ba) system has been synthesized by an auto-ignited combustion technique. The structure of the system is analyzed by powder X-ray diffraction and vibrational spectroscopic tools. The cation deficient zirconolite (CaZrTi₂O₇) is found to be a monoclinic structure with the space group C2/c. A narrow size distribution of the nanoparticles is observed by transmission electron microscopy with a peak at 11 nm. The optical band gap of the ceramics obtained by using Tauc’s plot is in between 3.10 eV and 3.30 eV. The photoluminescence emission spectra of the samples are investigated and the probable transitions producing the emissions are identified. The microstructure of the sintered pellets are examined by scanning electron microscopy and the elemental compositions are confirmed by energy-dispersive spectrometry. Impedance spectroscopic analysis of the sample showed that ions are the main source of conduction. Ionic conduction and grain boundary conduction stimulate high conductivity to the material. Electrical property measurements in the temperature range 500–850 °C indicate that CaZrTi₂O₇ is stable and can be utilized over a wide range of temperatures and frequencies. These materials are found suitable for optical and solid oxide fuel cell applications.

中文翻译：

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AZrTi 2 O 7（A = mg，ca，Sr和Ba）功能纳米陶瓷的合成与表征

通过自动点火燃烧技术合成了纳米晶AZrTi ₂ O ₇（A = Mg，Ca，Sr和Ba）体系。该系统的结构通过粉末X射线衍射仪和振动光谱仪进行分析。阳离子不足的锆钛矿（CaZrTi ₂ O ₇）被发现是具有C2 / c空间群的单斜结构。通过透射电子显微镜观察到纳米颗粒的窄尺寸分布，其峰值在11nm处。通过Tauc曲线获得的陶瓷的光学带隙在3.10 eV和3.30 eV之间。研究了样品的光致发光发射光谱，并确定了可能产生发射的跃迁。通过扫描电子显微镜检查烧结颗粒的微观结构，并通过能量分散光谱法确认元素组成。样品的阻抗谱分析表明，离子是主要的传导来源。离子传导和晶界传导刺激了材料的高传导性。₂ O ₇稳定，可以在广泛的温度和频率范围内使用。发现这些材料适用于光学和固体氧化物燃料电池应用。