Northwestern Univ., Evanston, IL (United States). Dept. of Chemistry
Northwestern Univ., Evanston, IL (United States). Dept. of Materials Science and Engineering
Northwestern Univ., Evanston, IL (United States). Dept. of Chemistry; Beihang Univ., Beijing (China). School of Materials Science and Engineering
Univ. of Michigan, Ann Arbor, MI (United States). Dept. of Physics
Northwestern Univ., Evanston, IL (United States). Dept. of Chemistry; Argonne National Lab. (ANL), Argonne, IL (United States). Materials Science Division
The broad-based implementation of thermoelectric materials in converting heat to electricity hinges on the achievement of high conversion efficiency. Here we demonstrate a thermoelectric figure of merit ZT of 2.5 at 923 K by the cumulative integration of several performance-enhancing concepts in a single material system. Using non-equilibrium processing we show that hole-doped samples of PbTe can be heavily alloyed with SrTe well beyond its thermodynamic solubility limit of <1 mol%. The much higher levels of Sr alloyed into the PbTe matrix widen the bandgap and create convergence of the two valence bands of PbTe, greatly boosting the power factors with maximal values over 30 μWcm -1 K -2. Exceeding the 5 mol% solubility limit leads to endotaxial SrTe nanostructures which produce extremely low lattice thermal conductivity of 0.5 Wm -1 K -1 but preserve high hole mobilities because of the matrix/precipitate valence band alignment. The best composition is hole-doped PbTe-8% SrTe.
Tan, Gangjian, et al. "Non-equilibrium processing leads to record high thermoelectric figure of merit in PbTe–SrTe." Nature Communications, vol. 7, Jul. 2016. https://doi.org/10.1038/ncomms12167
Tan, Gangjian, Shi, Fengyuan, Hao, Shiqiang, et al., "Non-equilibrium processing leads to record high thermoelectric figure of merit in PbTe–SrTe," Nature Communications 7 (2016), https://doi.org/10.1038/ncomms12167
@article{osti_1326596,
author = {Tan, Gangjian and Shi, Fengyuan and Hao, Shiqiang and Zhao, Li-Dong and Chi, Hang and Zhang, Xiaomi and Uher, Ctirad and Wolverton, Chris and Dravid, Vinayak P. and Kanatzidis, Mercouri G.},
title = {Non-equilibrium processing leads to record high thermoelectric figure of merit in PbTe–SrTe},
annote = {The broad-based implementation of thermoelectric materials in converting heat to electricity hinges on the achievement of high conversion efficiency. Here we demonstrate a thermoelectric figure of merit ZT of 2.5 at 923 K by the cumulative integration of several performance-enhancing concepts in a single material system. Using non-equilibrium processing we show that hole-doped samples of PbTe can be heavily alloyed with SrTe well beyond its thermodynamic solubility limit of -1 K -2. Exceeding the 5 mol% solubility limit leads to endotaxial SrTe nanostructures which produce extremely low lattice thermal conductivity of 0.5 Wm -1 K -1 but preserve high hole mobilities because of the matrix/precipitate valence band alignment. The best composition is hole-doped PbTe-8% SrTe.},
doi = {10.1038/ncomms12167},
url = {https://www.osti.gov/biblio/1326596},
journal = {Nature Communications},
issn = {ISSN 2041-1723},
volume = {7},
place = {United States},
publisher = {Nature Publishing Group},
year = {2016},
month = {07}}
Tan, Gangjian; Ohta, Michihiro; Kanatzidis, Mercouri G.
Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 377, Issue 2152https://doi.org/10.1098/rsta.2018.0450