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Abstract Eu5Sn2As6is a Zintl phase crystalizing in the orthorhombic space groupPbamwith one‐dimensional chains of corner‐shared SnAs4tetrahedra running in thec‐direction. Eu5Sn2As6has an impressive room temperature Seebeck of >100 μV/K and < – 100 μV/K at 600 K crossing fromp‐ ton‐type at 650 K. The maximum thermoelectric figure of merit,zT, for Eu5Sn2As6is small (0.075), comparable to that of the Zintl phase Ca5Al2Sb6whose thermoelectric performance was improved by doping Na onto the Ca sites. In this study, we show that the thermoelectric properties of Eu5Sn2As6can be improved by substituting with K or La. The series Eu5‐xKxSn2As6provides an increase in maximumzTof 0.22 forx=0.15 due to a decrease resistivity while the onset of bipolar conduction systematically increases in temperature. Upon La substitution, Eu5‐xLaxSn2As6results in a newn‐type Zintl phase across the temperature range of 300–800 K.
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Chemical Origins of Optically Addressable Spin States in Eu 2 (P 2 S 6 ) and Eu 2 (P 2 Se 6 )
- PAR ID:
- 10553983
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Materials Au
- Volume:
- 5
- Issue:
- 1
- ISSN:
- 2694-2461
- Format(s):
- Medium: X Size: p. 182-190
- Size(s):
- p. 182-190
- Sponsoring Org:
- National Science Foundation
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