"This is not a one-off discovery. Rather, we have developed and demonstrated a new way to create a whole new class of doped thermoelectric materials with superior properties," said Ramanath, a faculty member in the Department of Materials Science and Engineering at Rensselaer. "Our findings truly hold the potential to transform the technology landscape of refrigeration and make a real impact on our lives."
Results of the study are detailed in the Nature Materials paper "A new class of doped nanobulk high figure of merit thermoelectrics by scalable bottom-up assembly." See the paper online at: http://dx.doi.org/10.1038/NMAT3213
Trying to engineer thermoelectric materials is somewhat like playing a game of "tug of war," Ramanath said. Researchers endeavor to control three separate properties of the material: electrical conductivity, thermal conductivity, and Seebeck coefficient. Manipulating one of these properties, however, necessarily affects the other two. This new study demonstrates a new way to minimize the interdependence of these three properties by combining doping and nanostructuring in well-known thermoelectric materials such as tellurides and selenides based on bismuth and antimony.
The goal of tweaking these three properties is to create a thermoelectric material with a high figure of merit, or ZT, which is a measure of how efficient the material is at converting heat to electricity. The new pea-sized pellets of nanomaterials developed by the Rensselaer team demonstrated a ZT of 1 to 1.1 at room temperature. Since such high values are obtained even without optimizing the process, the researchers are confident that higher ZT can be obtained with some smart engineering.
"It's really ama
|Contact: Michael Mullaney|
Rensselaer Polytechnic Institute