Hinge-like structure induced unusual properties of black phosphorus and new strategies to improve the thermoelectric performance.

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 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 valle

SUBMITTER: Qin G 

PROVIDER: S-EPMC4221793 | biostudies-literature | 2014 Nov

REPOSITORIES: biostudies-literature