Wilhelm-Ostwald-Institut für Physikalische und Theoretische Chemie, Universität Leipzig , Linnéstraße 2, 04103 Leipzig, Germany.
J Am Chem Soc. 2017 Aug 30;139(34):11694-11697. doi: 10.1021/jacs.7b06296. Epub 2017 Aug 21.
The first metal-shrouded two-dimensional semiconductor, single-layer TlO, is discussed from first principles. It is thermally and dynamically stable, has a low cleavage energy calling for exfoliation from layered TlO bulk, and has a very small interface mismatch compared to (001) Tl metal. Single-layer TlO exhibits a direct bandgap of 1.56 eV and a very high charge carrier mobility of 4.3 × 10 cm V s. The metal-shrouded 2D semiconductor promises interesting applications in 2D electronics. An intriguing layer-thickness-dependent direct-to-indirect bandgap transition is observed, and contrary to early literature, the bulk is also a semiconductor.
本文从第一性原理出发，讨论了首例金属包裹的二维半导体材料——单层 TlO。它具有热力学和动力学稳定性，剥离能低，易于从 TlO 层状体中剥离，与（001）Tl 金属相比界面失配非常小。单层 TlO 的带隙为 1.56eV，载流子迁移率高达 4.3×10^4cm^2V^-1s^-1。这种金属包裹的二维半导体有望在二维电子学中得到广泛应用。我们观察到了有趣的层厚相关的直接-间接带隙转变，与早期文献相反，体材料也是半导体。
