论文标题
分层MX（M = SN，Pb; X = S，TE）化合物的热电和晶格动力学特性
Thermoelectric and lattice dynamics properties of layered MX (M = Sn, Pb; X = S, Te) compounds
论文作者
论文摘要
由于其有希望的热电（TE）特性，已广泛研究了铅和锡藻源。在降低维度时，已经报道了其TE效率的进一步提高，这是现代设备制造的重要特征。使用密度函数理论结合了半古典玻尔兹曼传输理论，我们研究了二维（2D）MX（M = SN，PB; X = S，TE）单层的结构，电子和TE特性。发现自旋轨道耦合对其电子结构具有重大影响，尤其是对于重型化合物。结构优化，随后是声子传输研究占了上风，矩形（γ-）相在能量上是对SNS和SNTE单层最有利的，而平方结构是PBS和PBTE单层最稳定的。我们的结果与以前的研究非常吻合。这些2D材料表现出较高的Seebeck系数和功率因子以及低晶格的导热率，这是优质TE材料的重要特征。对于N型SNS，SNTE，PBS和P-TYPE PBTE单层的最大值（ZT）为1.04、1.46、1.51和1.94，分别在700 K时分别高于其BOLK ZT值。因此，这些单层是有希望的TE应用程序的候选人。
Lead and tin chalcogenides have been studied widely due to their promising thermoelectric (TE) properties. Further enhancement in their TE efficiency has been reported upon the reduction of the dimension, which is an important feature in modern device fabrications. Using density functional theory combined with the Semi-classical Boltzmann transport theory, we studied the structural, electronic and TE properties of two-dimensional (2D) MX (M = Sn, Pb; X = S, Te) monolayers. Spin-orbit coupling was found to have significant effects on their electronic structure, particularly for the heavy compounds. Structural optimization followed by phonon transport studies prevailed that the rectangular (γ-) phase is energetically the most favorable for SnS and SnTe monolayers, whereas the square structure is found the most stable for PbS and PbTe monolayers. Our results are in good agreement with previous studies. These 2D materials exhibit high Seebeck coefficients and power factors along with low lattice thermal conductivities, which are essential features of good TE materials. The maximum figure of merits (ZT) of 1.04, 1.46, 1.51 and 1.94 are predicted for n-type SnS, SnTe, PBS and p-type PbTe monolayers respectively at 700 K, which are higher than their bulk ZT values. Hence, these monolayers are promising candidates for TE applications.
