@article{61a0d0a2b80442c28a5ed1f01dca0eb7,
title = "Exceptional thermoelectric performance in Mg3Sb0.6Bi1.4 for low-grade waste heat recovery",
abstract = "Bi2Te3 alloys have been the most widely used n-type material for low temperature thermoelectric power generation for over 50 years, thanks to the highest efficiency in the 300-500 K temperature range relevant for low-grade waste-heat recovery. Here we show that n-type Mg3Sb0.6Bi1.4, with a thermoelectric figure-of-merit zT of 1.0-1.2 at 400-500 K, finally surpasses n-type Bi2Te3. This exceptional performance is achieved by tuning the alloy composition of Mg3(Sb1-xBix)2. The two primary mechanisms of the improvement are the band effective-mass reduction and grain size enhancement as the Mg3Bi2 content increases. The benefit of the effective-mass reduction is only effective up to the optimum composition Mg3Sb0.6Bi1.4, after which a different band dominates charge transport. The larger grains are important for minimizing grain-boundary electrical resistance. Considering the limited choice for low temperature n-type thermoelectric materials, the development of Mg3Sb0.6Bi1.4 is a significant advancement towards sustainable heat recovery technology.",
author = "Kazuki Imasato and Kang, {Stephen Dongmin} and Snyder, {G. Jeffrey}",
note = "Funding Information: The authors would like to acknowledge support from the NASA Science Mission Directorate{\textquoteright}s Radioisotope Power Systems Thermoelectric Technology Development program. KI acknowledges support from the Funai Foundation for Information Technology. The EBSD in this work made use of the EPIC facility of Northwestern University{\textquoteright}s NUANCE Center, which has received support from: the Soft and Hybrid Nanotechnology Experimental Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR-1720139) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; the State of Illinois, through the IIN. Funding Information: The authors would like to acknowledge support from the NASA Science Mission Directorate's Radioisotope Power Systems Thermoelectric Technology Development program. KI acknowledges support from the Funai Foundation for Information Technology. The EBSD in this work made use of the EPIC facility of Northwestern University's NUANCE Center, which has received support from: the Soft and Hybrid Nanotechnology Experimental Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR-1720139) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; the State of Illinois, through the IIN. Publisher Copyright: {\textcopyright} 2019 The Royal Society of Chemistry.",
year = "2019",
month = mar,
doi = "10.1039/c8ee03374a",
language = "English (US)",
volume = "12",
pages = "965--971",
journal = "Energy and Environmental Science",
issn = "1754-5692",
publisher = "Royal Society of Chemistry",
number = "3",
}
