Motivated by interesting physical and chemical properties created by doping and topological quantum state, we perform the density functional theory and the Boltzmann transport equation to systematically investigate the geometric structures, stabilities, electronic structures, thermal conductivities and thermoelectric properties for Sb and its oxidations (Sb2O and SbO). The predicted lattice thermal conductivity (k L ) of Sb is 11.6 nW K-1 at 300 K, but it would fall drastically when introducing O atoms. This is mainly attributed to the strong anharmonic interactions by adding O atoms, and few contributions are from the decreasing phonon group velocities caused by the compressed phonon spectrum. SbO has been proven as a topological insulator with a relatively large topological band gap (E g ) ∼ 0.156 eV, and meanwhile its carrier mobilities (345.78 cm2/Vs for electrons) and scattering time (44.27 × 10-14 s for electrons) are also rather high among all 2D materials, exhibiting the excellent thermoelectric performance. The calculated maximum thermoelectric figure of merit ([Formula: see text]) of the three Sb films for optimum n-type doping are close to each other at 300 K, but with an increasing temperature, the [Formula: see text] of Sb for optimum n-type doping climbs quickly and can reach up to 0.73 at 700 K, which is far higher than others. More interestingly, the [Formula: see text] of SbO can be increased sharply at 300 K after considering spin-orbit coupling (SOC): 0.50 for optimum p-type doping and 0.41 for optimum n-type doping. However, only the tiny changes in the [Formula: see text] of Sb can be found before and after considering SOC. Our research reveals how the doping and the topological quantum state affect thermoelectric performances, providing reference to design and search high [Formula: see text] thermoelectric materials in future.

中文翻译：

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锑薄膜的热电性能：氧化作用和拓扑量子态

受掺杂和拓扑量子态产生的有趣物理和化学性质的启发，我们执行密度泛函理论和玻尔兹曼输运方程，以系统地研究 Sb 及其氧化物 (Sb2O) 的几何结构、稳定性、电子结构、热导率和热电性质和 SbO)。Sb 的预测晶格热导率 (k L ) 在 300 K 时为 11.6 nW K-1，但在引入 O 原子时会急剧下降。这主要归因于通过添加 O 原子产生的强非谐相互作用，而由压缩声子谱引起的声子群速度降低的贡献很少。SbO 已被证明是一种拓扑绝缘体，具有相对较大的拓扑带隙 (E g ) ~ 0.156 eV，同时其载流子迁移率 (345. 电子的 78 cm2/Vs）和散射时间（电子的 44.27 × 10-14 s）在所有二维材料中也相当高，表现出优异的热电性能。用于最佳 n 型掺杂的三种 Sb 薄膜的计算最大热电品质因数（[公式：见正文]）在 300 K 时彼此接近，但随着温度的升高，Sb 的 [公式：见正文]最佳 n 型掺杂迅速攀升，在 700 K 时可达 0.73，远高于其他掺杂。更有趣的是，在考虑自旋轨道耦合 (SOC) 后，SbO 的 [公式：见正文] 可以在 300 K 时急剧增加：0.50 用于最佳 p 型掺杂，0.41 用于最佳 n 型掺杂。然而，在考虑 SOC 之前和之后，只能发现 Sb [公式：见正文] 的微小变化。