Nautiyal Himanshu, Scardi Paolo
Department of Civil, Environmental & Mechanical Engineering, University of Trento, via Mesiano 77, 38123, Trento, Italy.
Nanotechnology. 2022 May 20;33(32). doi: 10.1088/1361-6528/ac6c37.
Tin-based chalcogenides are of increasing interest for thermoelectric applications owing to their low-cost, earth-abundant, and environmentally friendly nature. This is especially true for 2D materials, in which breaking of the structural symmetry plays a crucial role in tuning the electronic properties. 2D materials present a unique opportunity to manipulate the electronic and thermal properties by transforming a monolayer into a Janus monolayer. In the present work, we have investigated the thermoelectric properties of hexagonal SnS, SnSemonolayer, and Janus SnSSe monolayer. Density functional theoretical calculations points out the hexagonal Janus SnSSe monolayer as a potential high-performing thermoelectric material. Results for the Janus SnSSe monolayer show an ultra-low thermal conductivity originating from the low group velocity of the low-lying optical modes, leading to superiorvalues of 0.5 and 3 at 300 K and 700 K for thetype doping, respectively.
基于锡的硫族化合物因其低成本、储量丰富且环保的特性，在热电应用中越来越受到关注。对于二维材料而言尤其如此，其中结构对称性的破坏在调节电子性质方面起着关键作用。二维材料提供了一个独特的机会，可通过将单层转变为Janus单层来操纵电子和热性质。在本工作中，我们研究了六方相SnS、SnSe单层和Janus SnSSe单层的热电性质。密度泛函理论计算指出六方相Janus SnSSe单层是一种潜在的高性能热电材料。Janus SnSSe单层的结果表明，其超低的热导率源于低能光学模式的低群速度，分别导致在300 K和700 K时，p型掺杂的优值为0.5和3。
