The development of ultrathin, stable ferroelectric materials is crucial for advancing high-density, low-power electronic devices. Nonetheless, ultrathin ferroelectric materials are rare due to the critical size effect. Here, a novel ferroelectric material, magnesium molybdenum oxide (Mg₂Mo₃O₈) is presented. High-quality ultrathin Mg₂Mo₃O₈ crystals are synthesized using chemical vapor deposition (CVD). Ultrathin Mg₂Mo₃O₈ has a wide bandgap (≈4.4 eV) and nonlinear optical response. Mg₂Mo₃O₈ crystals of varying thicknesses exhibit out-of-plane ferroelectric properties at room temperature, with ferroelectricity retained even at a 2 nm thickness. The Mg₂Mo₃O₈ exhibits a relatively large remanent polarization ranging from 33 to 52 µC cm⁻², which is tunable by changing its thickness. Notably, Mg₂Mo₃O₈ possesses a high Curie temperature (>980 °C) across various thicknesses. Moreover, the as-grown Mg₂Mo₃O₈ crystals display remarkable stability under harsh environments. This work introduces nolanites-type crystal into ultrathin ferroelectrics. The scalable synthesis of stable ultrathin ferroelectric Mg₂Mo₃O₈ expands the scope of ferroelectric materials and may prosper applications of ferroelectrics.

中文翻译：

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高品质超薄铁电氧化钼镁的可规模化合成

超薄、稳定的铁电材料的开发对于推进高密度、低功耗电子设备至关重要。尽管如此，由于临界尺寸效应，超薄铁电材料很少见。这里，提出了一种新型铁电材料——镁钼氧化物（Mg ₂ Mo ₃ O _{8 ）。}采用化学气相沉积 (CVD) 合成高质量超薄 Mg ₂ Mo ₃ O _8晶体。超薄Mg ₂ Mo ₃ O ₈具有宽带隙（≈4.4 eV）和非线性光学响应。不同厚度的Mg ₂ Mo ₃ O ₈晶体在室温下表现出面外铁电特性，即使在2 nm厚度下也能保持铁电性。Mg ₂ Mo ₃ O ₈表现出相对较大的剩余极化，范围为33至52 µC cm ^{- 2}，可通过改变其厚度来调节。值得注意的是，Mg ₂ Mo ₃ O ₈在各种厚度上都具有高居里温度（> 980 °C）。此外，生长的Mg ₂ Mo ₃ O ₈晶体在恶劣环境下表现出显着的稳定性。这项工作将诺兰石型晶体引入超薄铁电体中。稳定的超薄铁电Mg ₂ Mo ₃ O ₈的可规模合成扩大了铁电材料的范围，并可能繁荣铁电的应用。