Abstract Ferroelectric materials with high Curie temperatures, TC, and tuning of the TC over a large temperature range are very important for the basic sciences and engineering. This paper reviews the various types of high-temperature ferroelectrics with perovskite, bismuth layered, tungsten bronze, and perovskite slab structures, especially Sr2Nb2O7 with TC = 1342 °C and its family. The lattice instability of the high-temperature ferroelectric phase transitions is also discussed. The superior tunability of the TC is achieved by the substitution of cations at the A- and B-sites in the perovskite-like structures. The variation of the soft optic and relaxation modes and elastic anomalies related to structural phase transitions were discussed in relation to the A- and B-site substitutions of oxygen octahedral ferroelectrics, especially Ba2NaNb5(1-x)Ta5xO15 with a tungsten bronze structure and (BaxSr1-x)2Nb2O7, Sr2(Nb1-xTax)2O7 with the perovskite slab structure.

中文翻译：

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超高居里温度铁电体和卓越的 TC 可调性：晶格不稳定性和铁电相变

摘要 具有高居里温度、TC 和 TC 在大温度范围内调谐的铁电材料对于基础科学和工程非常重要。本文综述了具有钙钛矿、铋层状、钨青铜和钙钛矿板状结构的各种类型的高温铁电体，特别是 TC = 1342 °C 的 Sr2Nb2O7 及其家族。还讨论了高温铁电相变的晶格不稳定性。通过在类钙钛矿结构中的 A 位和 B 位取代阳离子，可以实现 TC 的优异可调性。讨论了与氧八面体铁电体的 A 位和 B 位取代相关的软光学和弛豫模式的变化以及与结构相变相关的弹性异常，