Nowadays, there has been significant interest in two-dimensional (2D) materials for thermoelectrical (TE) application due to their intrinsic high electrical conductivity and weak phonon transport ability. Since a series of novel 2D 7-atomic materials (such as the MoSi₂N₄ monolayer) have been proposed (Y. L. Hong et al., Science, 2020, 369, 670), some of them are expected to be potential TE materials. In this study, through a combination of first-principles calculations and semi-classical Boltzmann transport theory, we systemically investigate the electrical and thermal transport properties of the original 2D ZrSn₂N₄ monolayer. It is interesting to find that p-type (n-type) doped ZrSn₂N₄ has a high PF value of 3.13 (2.71) mW m⁻¹ K⁻² at 1200 K. Besides, the high phonon anharmonic scattering results in a low thermal conductivity of 3.27 (3.57) W m⁻¹ K⁻¹ for p-type (n-type) ZrSn₂N₄ at 1200 K. Consequently, the optimal ZT values for p-type (n-type) doped ZrSn₂N₄ show a moderate level of 1.15 (0.91) at 1200 K. These results suggest the great potential of the ZrSn₂N₄ monolayer as a TE material.

中文翻译：

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新型二维单层ZrSn2N4热电性能的理论预测

如今，由于二维（2D）材料固有的高电导率和弱声子传输能力，人们对热电（TE）应用产生了浓厚的兴趣。由于一系列新型2D 7原子材料（例如MoSi ₂ N ₄单层）被提出（YL Hong等人，Science，2020, 369 , 670），其中一些有望成为潜在的TE材料。在本研究中，通过结合第一性原理计算和半经典玻尔兹曼输运理论，我们系统地研究了原始二维ZrSn ₂ N ₄单层的电和热输运特性。有趣的是，p型（n型）掺杂ZrSn ₂ N _{4在1200 K时具有3.13 (2.71) mW m} ^-1 K ^-2的高PF值。此外，高声子非简声散射导致p 型（n 型）ZrSn ₂ N _{4在 1200 K 时具有 3.27 (3.57) W m} ^-1 K ^-1的低热导率。因此， p 型（n 型）掺杂 ZrSn ₂的最佳ZT值N ₄在1200 K 时显示出1.15 (0.91) 的中等水平。这些结果表明ZrSn ₂ N ₄单层作为TE 材料的巨大潜力。