Thermoelectric materials, which convert heat energy to electrical energy, may become increasingly important in the world’s energy situation. Through the inclusion of nanoscale features embedded within a thermoelectric bulk material, it has been shown that a corresponding decrease in lattice thermal conductivity results in an enhanced thermoelectric figure of merit, ZT. This project focused on a new method of nanostructuring: lowering the lattice thermal conductivity by generating a two-phase material in which one phase had nanoscale layers to scatter phonons. The thermoelectric properties of metal chalcogenides with SnSe were investigated for three systems: PbTe-SnSe, PbSe-SnSe, and SnTe-SnSe. PbTe-SnSe formed a solid solution with decreased thermal conductivity over PbTe but poor ZT. PbSe-SnSe and SnTe-SnSe formed multiphase systems with significantly decreased thermal conductivities compared to their parent materials at room temperature (maximum 26.2% and 87%, respectively). In addition, SnTe-SnSe showed promise for further research because it is naturally p-type, less toxic than lead-based materials, and showed a maximum ZT of 0.45 at 700K for a SnTe-SnSe 20% sample.

Last modified

• 07/24/2018

Creator

• Steven N. Girard
• Katherine R. Stevens
• Simon Johnsen
• Mercouri G. Kanatzidis

DOI

• https://doi.org/10.21985/N2F419

Keyword

• Volume 7

Date created

• 2010

Resource type

• Article

Rights statement

• In Copyright