TY - JOUR
T1 - Dual Alloying Strategy to Achieve a High Thermoelectric Figure of Merit and Lattice Hardening in p-Type Nanostructured PbTe
AU - Sarkar, Sumanta
AU - Zhang, Xiaomi
AU - Hao, Shiqiang
AU - Hua, Xia
AU - Bailey, Trevor P.
AU - Uher, Ctirad
AU - Wolverton, Chris
AU - Dravid, Vinayak P.
AU - Kanatzidis, Mercouri G.
N1 - Funding Information:
This work was supported by the Department of Energy, Office of Science Basic Energy Sciences under grant DE-SC0014520, DOE Office of Science. This work made use of the NUFAB-COOK and MatCI Facilities which receive support from the MRSEC Program (NSF DMR-1720139) of the Materials Research Center at Northwestern University. This work also made use of EPIC (JEOL 2100F TEM, Hitachi HD-2300 Dual EDS Cryo STEM, Fischione Model 1050 TEM Mill, and PHI TRIFT III ToF-SIMS) facility of Northwestern University’s NUANCE Center, which has received support from the Soft and Hybrid Nanotechnology Experimental (SHyNE) Resource (NSF ECCS-1542205); the MRSEC program (NSF DMR-1720139) at the Materials Research Center; the International Institute for Nanotechnology (IIN); the Keck Foundation; and the State of Illinois, through the IIN. Temperature-dependent Hall measurements were supported by the U.S. Department of Energy, Office of Science, and Office of Basic Energy Sciences under Award Number DE-SC-0008574.
Publisher Copyright:
© Copyright 2018 American Chemical Society.
PY - 2018/10/12
Y1 - 2018/10/12
N2 - The introduction of an alkaline earth metal telluride as a second phase in PbTe can lead to very high thermoelectric figure of merit, ZT, as a result of hierarchical structuring, e.g., in the PbTe-SrTe system. However, there are two roadblocks to this strategy: poor solubility and occurrence of incoherent nanoprecipitates in the PbTe matrix, e.g., the PbTe-BaTe system. Here we demonstrate a dual alloying approach by simultaneously alloying CaTe and BaTe in the p-type PbTe matrix to achieve ZTmax ranging up to ∼2.2 at high temperatures. Synergistic enhancement of the Seebeck coefficient via favorable band convergence gives rise to higher power factors up to 34 μW cm-1 K-2 and significant suppression of lattice thermal conductivity, IL, down to ∼0.6 W m-1 K-1 results from large multicenter phonon scattering. Additionally, co-inclusion of Ca and Ba causes unanticipated lattice hardening in otherwise brittle PbTe, essential for practical device applications.
AB - The introduction of an alkaline earth metal telluride as a second phase in PbTe can lead to very high thermoelectric figure of merit, ZT, as a result of hierarchical structuring, e.g., in the PbTe-SrTe system. However, there are two roadblocks to this strategy: poor solubility and occurrence of incoherent nanoprecipitates in the PbTe matrix, e.g., the PbTe-BaTe system. Here we demonstrate a dual alloying approach by simultaneously alloying CaTe and BaTe in the p-type PbTe matrix to achieve ZTmax ranging up to ∼2.2 at high temperatures. Synergistic enhancement of the Seebeck coefficient via favorable band convergence gives rise to higher power factors up to 34 μW cm-1 K-2 and significant suppression of lattice thermal conductivity, IL, down to ∼0.6 W m-1 K-1 results from large multicenter phonon scattering. Additionally, co-inclusion of Ca and Ba causes unanticipated lattice hardening in otherwise brittle PbTe, essential for practical device applications.
UR - http://www.scopus.com/inward/record.url?scp=85054604169&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85054604169&partnerID=8YFLogxK
U2 - 10.1021/acsenergylett.8b01684
DO - 10.1021/acsenergylett.8b01684
M3 - Article
AN - SCOPUS:85054604169
SN - 2380-8195
VL - 3
SP - 2593
EP - 2601
JO - ACS Energy Letters
JF - ACS Energy Letters
IS - 10
ER -
