More Like this

1. Impact of Lu-Substitution in Yb _14–x Lu _x ZnSb ₁₁ : Thermoelectric Properties and Oxidation Studies

   https://doi.org/10.1021/acsaem.3c01756  

   Justl, Andrew P.; Winston, Logan D.; Bux, Sabah K.; Kauzlarich, Susan M. (October 2023, ACS Applied Energy Materials)
2. Discovery of multivalley Fermi surface responsible for the high thermoelectric performance in Yb ₁₄ MnSb ₁₁ and Yb ₁₄ MgSb ₁₁

   https://doi.org/10.1126/sciadv.abe9439  

   Perez, Christopher J.; Wood, Maxwell; Ricci, Francesco; Yu, Guodong; Vo, Trinh; Bux, Sabah K.; Hautier, Geoffroy; Rignanese, Gian-Marco; Snyder, G. Jeffrey; Kauzlarich, Susan M. (January 2021, Science Advances)

   null (Ed.)

   The Zintl phases, Yb 14 M Sb 11 ( M = Mn, Mg, Al, Zn), are now some of the highest thermoelectric efficiency p-type materials with stability above 873 K. Yb 14 MnSb 11 gained prominence as the first p-type thermoelectric material to double the efficiency of SiGe alloy, the heritage material in radioisotope thermoelectric generators used to power NASA’s deep space exploration. This study investigates the solid solution of Yb 14 Mg 1− x Al x Sb 11 (0 ≤ x ≤ 1), which enables a full mapping of the metal-to-semiconductor transition. Using a combined theoretical and experimental approach, we show that a second, high valley degeneracy ( N v = 8) band is responsible for the groundbreaking performance of Yb 14 M Sb 11 . This multiband understanding of the properties provides insight into other thermoelectric systems (La 3− x Te 4 , SnTe, Ag 9 AlSe 6 , and Eu 9 CdSb 9 ), and the model predicts that an increase in carrier concentration can lead to zT > 1.5 in Yb 14 M Sb 11 systems. 

   more » « less
3. Advancing the Ca ₁₄ AlSb ₁₁ Structure Type: Synthesis and Characterization of Yb ₁₄ CdSb ₁₁ for Thermoelectric Applications

   https://doi.org/10.1002/zaac.202500015  

   Opara, Ivan Chinonso; Fettinger, James C; Star, Kurt E; Bux, Sabah K; Shen, Zihao; Taufour, Valentin; Kauzlarich, Susan M (April 2025, Zeitschrift für anorganische und allgemeine Chemie)

   The ternary phase, Yb14CdSb11, has been synthesized by flux and polycrystalline methods. The crystal structure is determined via single-crystal X-ray diffraction, revealing that it crystallizes in the Ca14AlSb11 structure type (I41/acd space group with unit cell parameters of a = 16.5962(2) & Aring; and c = 22.1346(5) & Aring;, 90 K, Z = 8, R1 = 2.65%, and wR2 = 4.58%). The polycrystalline form of the compound is synthesized from a stoichiometric reaction of Yb4Sb3, CdSb, Yb, and Sb. The elemental composition is confirmed using scanning electron microscopy and energy-dispersive spectroscopy, and phase purity is verified by powder X-ray diffraction. Thermoelectric measurements, including resistivity, Seebeck coefficient, thermal conductivity, Hall carrier concentration, and Hall mobility, are conducted from 300 to 1273 K. Yb14CdSb11 exhibits a peak zT = 0.90 at 1200 K. Carrier concentration and Hall mobility range from 6.99 x 1020-1.01 x 1021 cm-3 and 4.45-9.35 x 10-1 cm2 V-1 s-1, respectively. This carrier concentration is lower than that reported for the Zn or Mn analogs leading to a lower thermoelectric figure of merit at high temperatures. However, with appropriate doping, this phase should also be a promising p-type candidate for high-temperature energy conversion applications. 

   more » « less
4. Probing High-Temperature Oxidation of Thermoelectric Phases Yb ₁₄ M Sb ₁₁ ( M = Mg, Mn, Zn)

   https://doi.org/10.1021/acsami.2c13093  

   Justl, Andrew P.; Kauzlarich, Susan M. (October 2022, ACS Applied Materials & Interfaces)
5. Evolution of Thermoelectric Properties in the Triple Cation Zintl Phase: Yb _13–x Ca _x BaMgSb ₁₁ ( x = 1–6)

   https://doi.org/10.1021/acs.chemmater.1c02584  

   Perez, Christopher J.; Cerretti, Giacomo; Wille, Elizabeth L.; Devlin, Kasey P.; Grewal, Navtej S.; Justl, Andrew P.; Wood, Maxwell; Bux, Sabah K.; Kauzlarich, Susan M. (October 2021, Chemistry of Materials)