Shanghai Ultra-precision Optical Manufacturing Engineering Research Center and Key Laboratory of Micro and Nano Photonic Structures (Ministry of Education), Department of Optical Science and Engineering, Fudan University , Shanghai 200433, China.
Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences , Ningbo 315201, China.
ACS Appl Mater Interfaces. 2016 Aug 17;8(32):20977-85. doi: 10.1021/acsami.6b04211. Epub 2016 Aug 5.
The dumbbell structure of two-dimensional group IV material offers alternatives to grow thin films for diverse applications. Thermal properties are important for these applications. We obtain the lattice thermal conductivity of low-buckled (LB) and dumbbell (DB) silicene by using first-principles calculations and the Boltzmann transport equation for phonons. For LB silicene, the calculated lattice thermal conductivity with naturally occurring isotope concentrations is 27.72 W/mK. For DB silicene, the calculated value is 2.86 W/mK. The thermal conductivity for DB silicene is much lower than LB silicene due to stronger phonon scattering. Our results will induce further theoretical and experimental investigations on the thermoelectric (TE) properties of DB silicene. The size-dependent thermal conductivity in both LB and DB silicene is investigated as well for designing TE devices. This work sheds light on the manipulation of phonon transport in two-dimensional group IV materials by dumbbell structure formed from the addition of adatoms.
二维 IV 族材料的哑铃结构为各种应用提供了生长薄膜的替代品。热性能对于这些应用很重要。我们通过第一性原理计算和玻尔兹曼输运方程对低弯曲（LB）和哑铃（DB）硅烯的晶格热导率进行了计算。对于 LB 硅烯，在考虑天然同位素浓度的情况下，计算出的晶格热导率为 27.72 W/mK。对于 DB 硅烯，计算值为 2.86 W/mK。由于声子散射更强，DB 硅烯的热导率远低于 LB 硅烯。我们的结果将促使进一步对 DB 硅烯的热电器件性能进行理论和实验研究。我们还研究了 LB 和 DB 硅烯的尺寸依赖性热导率，以设计热电器件。这项工作为通过添加 adatoms 形成的哑铃结构来操纵二维 IV 族材料中的声子输运提供了启示。
