Thermal conductivity in Bi_0.5Sb_1.5Te_3+x and the role of dense dislocation arrays at grain boundaries.

ABSTRACT: Several prominent mechanisms for reduction in thermal conductivity have been shown in recent years to improve the figure of merit for thermoelectric materials. Such a mechanism is a hierarchical all-length-scale architecturing that recognizes the role of all microstructure elements, from atomic to nano to microscales, in reducing (lattice) thermal conductivity. In this context, there have been recent claims of remarkably low (lattice) thermal conductivity in Bi_0.5Sb_1.5Te₃ that are attributed to seemingly ordinary grain boundary dislocation networks. These high densities of dislocation networks in Bi_0.5Sb_1.5Te₃ were generated via unconventional materials processing with excess Te (which formed liquid phase, thereby facilitati

SUBMITTER: Deng R 

PROVIDER: S-EPMC5983911 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature