Abstract We systematically investigate the structural, electronic properties of bulk CeO2, its H-phase and T-phase monolayers, studied using first-principles calculations based on density functional theory (DFT). The calculated electronic bandgap is 2.02 eV, 0.86 eV and 2.52 eV for CeO2 bulk, H-phase and T-phase, respectively. Here, the bandgap is tuned by applying triaxial tensile strain up to 28%. Using strain engineering, the bandgap further increases and behaves as a metal at about 28% for the bulk as well as its monolayers. It is found that for bulk CeO2, initially, the bandgap increases for strains up to 16% and then decreases. Similarly, for H-phase the bandgap increases initially at 4% strain and then decreases. Whereas, for T-phase, on applying strain the band gap decreases. Here, the bandgap is in visible range due to that it will be used in optoelectronic devices such as solar cells and LEDs. The result also shows that the CeO2 nanostructures have diverse electronic properties, tunable by strain engineering and have wide applications in nanoelectronics and nanodevices.

中文翻译：

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使用第一性原理计算的 CeO2 单层的结构和电学特性

摘要 我们系统地研究了块状 CeO2 及其 H 相和 T 相单层的结构、电子特性，并使用基于密度泛函理论 (DFT) 的第一性原理计算进行了研究。对于 CeO2 体、H 相和 T 相，计算出的电子带隙分别为 2.02 eV、0.86 eV 和 2.52 eV。在这里，通过施加高达 28% 的三轴拉伸应变来调整带隙。使用应变工程，带隙进一步增加并表现为块状及其单层的约 28% 的金属。发现对于块体 CeO2，最初，带隙随着应变增加 16%，然后减小。类似地，对于 H 相，带隙最初在 4% 应变时增加，然后减小。而对于 T 相，在施加应变时，带隙减小。这里，带隙在可见范围内，因为它将用于太阳能电池和 LED 等光电器件。结果还表明，CeO2 纳米结构具有多种电子特性，可通过应变工程进行调节，在纳米电子学和纳米器件中具有广泛的应用。