Details

Autor(en) / Beteiligte

• Qin, Guangzhao
• Qin, Zhenzhen
• Fang, Wu-Zhang
• Zhang, Li-Chuan
• Yue, Sheng-Ying
• Yan, Qing-Bo
• Hu, Ming
• Su, Gang

Titel

Diverse anisotropy of phonon transport in two-dimensional group IV-VI compounds: A comparative study

Ist Teil von

• Nanoscale, 2016-06, Vol.8 (21), p.1136-11319

Ort / Verlag

England

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• New classes of two-dimensional (2D) materials beyond graphene, including layered and non-layered, and their heterostructures, are currently attracting increasing interest due to their promising applications in nanoelectronics, optoelectronics and clean energy, where thermal transport is a fundamental physical parameter. In this paper, we systematically investigated the phonon transport properties of the 2D orthorhombic group IV-VI compounds of GeS, GeSe, SnS and SnSe by solving the Boltzmann transport equation (BTE) based on first-principles calculations. Despite their similar puckered (hinge-like) structure along the armchair direction as phosphorene, the four monolayer compounds possess diverse anisotropic properties in many aspects, such as phonon group velocity, Young's modulus and lattice thermal conductivity ( κ ), etc . Especially, the κ along the zigzag and armchair directions of monolayer GeS shows the strongest anisotropy while monolayer SnS and SnSe show almost isotropy in phonon transport. The origin of the diverse anisotropy is fully studied and the underlying mechanism is discussed in details. With limited size, the κ could be effectively lowered, and the anisotropy could be effectively modulated by nanostructuring, which would extend the applications to nanoscale thermoelectrics and thermal management. Our study offers fundamental understanding of the anisotropic phonon transport properties of 2D materials, and would be of significance for further study, modulation and applications in emerging technologies. The four monolayer group IV-VI compounds (GeS, GeSe, SnS and SnSe), although possessing similar hinge-like structure along the armchair direction, show diverse anisotropic properties in phonon transport.