Tinselenidene: a Two-dimensional Auxetic Material with Ultralow Lattice Thermal Conductivity and Ultrahigh Hole Mobility
Li-Chuan Zhang1, Guangzhao Qin1, Wu-Zhang Fang2, Hui-Juan Cui2, Qing-Rong Zheng2, Qing-Bo Yan1 & Gang Su2
1College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing,
China 100049.
2School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China 100049.
Correspondence and requests for materials should be addressed to Q.-B.Y. (email: yan@ucas.ac.cn) or G.S. (email:
gsu@ucas.ac.cn)
By means of extensive ab initio calculations, a new two-dimensional (2D) atomic material tin selenide monolayer (coined as tinselenidene) is predicted to be a semiconductor with an indirect gap (~1.45 eV) and a high hole mobility (of order 10000 cm2V−1S−1), and will bear an indirect-direct gap transition under a rather low strain (<0.5 GPa). Tinselenidene has a very small Young’s modulus (20–40 GPa) and an ultralow lattice thermal conductivity (<3 Wm−1K−1 at 300 K), making it probably the most flexible and most heat-insulating material in known 2D atomic materials. In addition, tinseleniden has a large negative Poisson’s ratio of −0.17, thus could act as a 2D auxetic material. With these intriguing properties, tinselenidene could have wide potential applications in thermoelectrics, nanomechanics and optoelectronics.
