About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Energy Materials for Sustainable Development
|
| Presentation Title |
Thermoelectric Properties of Transition Metal Dichalcogenide Alloys and Heterostructures |
| Author(s) |
Zlatan Aksamija |
| On-Site Speaker (Planned) |
Zlatan Aksamija |
| Abstract Scope |
Improving the thermoelectric (TE) figure-of-merit (ZT) requires either improving the power factor PF=S2&#\963; or decreasing the thermal conductivity of the material. The latter is strongly affected by mass-difference scattering when forming alloys of two materials. To date, several studies have investigated the TE performance of transition-metal dichalcogenides (TMDs). However, little has been done to investigate the TE properties of TMD alloys. Here we use numerical modeling of transport in the Boltzmann formalism with first-principles Density Functional Theory (DFT) calculations of electronic structure to investigate the effects of alloying on TE properties of 2D monolayer TMDs. We find that alloying decreases lattice thermal conductivity 5- to 6-fold while reducing carrier mobility by a modest amount. Alloying the transition metals Mo and W in sulfides produces the highest ZT due to the smallest band offsets between the constituents. We also show that reducing sample dimensions increases ZT by further reducing thermal conductivity. |