학술논문
Hinge-like structure induced unusual properties of black phosphorus and new strategies to improve the thermoelectric performance
Document Type
Working Paper
Author
Source
Scientific Reports 4, 6946 (2014)
Subject
Language
Abstract
We systematically investigated the geometric, electronic and thermoelectric (TE) properties of bulk black phosphorus (BP) under strain. The hinge-like structure of BP brings unusual mechanical responses such as anisotropic Young's modulus and negative Poisson's ratio. A sensitive electronic structure of BP makes it transform among metal, direct and indirect semiconductors under strain. The maximal figure of merit $ZT$ of BP is found to be 0.72 at $800\,\mathrm{K}$ that could be enhanced to 0.87 by exerting an appropriate strain, revealing BP could be a potential medium-high temperature TE material. Such strain-induced enhancements of TE performance are often observed to occur at the boundary of the direct-indirect band gap transition, which can be attributed to the increase of degeneracy of energy valleys at the transition point. By comparing the structure of BP with SnSe, a family of potential TE materials with hinge-like structure are suggested. This study not only exposes various novel properties of BP under strain, but also proposes effective strategies to seek for better TE materials.
Comment: 6 figures. Supplemental Information is available in Scientific Reports and also involved in this source package
Comment: 6 figures. Supplemental Information is available in Scientific Reports and also involved in this source package