Gupta Raveena, Dongre Bonny, Bera Chandan, Carrete Jesús
Institute of Nano Science and Technology, Habitat Center, Phase-X, Mohali, Punjab 160062, India.
Centre for Nanoscience and Nanotechnology, Panjab University, Sector-25, Chandigarh 160036, India.
J Phys Chem C Nanomater Interfaces. 2020 Aug 13;124(32):17476-17484. doi: 10.1021/acs.jpcc.0c03414. Epub 2020 Jul 16.
Several ternary "Janus" metal dichalcogenides such as {Mo,Zr,Pt}-SSe have emerged as candidates with significant potential for optoelectronic, piezoelectric, and thermoelectric applications. SnSSe, a natural option to explore as a thermoelectric given that its "parent" structures are SnS and SnSe has, however, only recently been shown to be mechanically stable. Here, we calculate the lattice thermal conductivities of the Janus SnSSe monolayer along with those of its parent dicalchogenides. The phonon frequencies of SnSSe are intermediate between those of SnSe and SnS; however, its thermal conductivity is the lowest of the three and even lower than that of a random Sn[SSe] alloy. This can be attributed to the breakdown of inversion symmetry and manifests as a subtle effect beyond the reach of the relaxation-time approximation. Together with its low favorable power factor, its thermal conductivity confirms SnSSe as a good candidate for thermoelectric applications.
几种三元“Janus”金属二硫属化物，如{Mo,Zr,Pt}-SSe，已成为在光电子、压电和热电应用方面具有巨大潜力的候选材料。鉴于其“母体”结构为SnS和SnSe，SnSSe作为一种热电材料是一个自然的探索选择，然而，直到最近才证明它具有机械稳定性。在这里，我们计算了Janus SnSSe单层及其母体二硫属化物的晶格热导率。SnSSe的声子频率介于SnSe和SnS之间；然而，它的热导率是三者中最低的，甚至低于随机Sn[SSe]合金的热导率。这可以归因于反演对称性的破坏，并且表现为超出弛豫时间近似范围的微妙效应。连同其较低的良好功率因数，其热导率证实SnSSe是热电应用的良好候选材料。
