TY - JOUR
T1 - Designing Environmentally Friendly High- zT Zn4Sb3 via Thermodynamic Routes
AU - Wu, Hsin Jay
AU - Wei, Pai-Chun
AU - Su, Hui Yi
AU - Wang, Kuang Kuo
AU - Yen, Wan Ting
AU - Jen, I. Lun
AU - He, Jian
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: We acknowledge the financial support from the Young Scholar Fellowship Program by Ministry of Science and Technology (MOST) in Taiwan, under Grant MOST 108-2636-E-110-001.
PY - 2019/10/9
Y1 - 2019/10/9
N2 - Zn4Sb3-based compounds constitute a lead-free material family with a best thermoelectric figure of merit (zT) in the midtemperature range. Unlike being a stoichiometric compound, the mutual solubility of Zn and Sb elicits rich microstructures and the structural instability of Zn4Sb3. The solubility limit and neighboring phase relations are crucial for the delicate balance between the thermoelectric performance and phase stability of Zn4Sb3. In this work, we constructed the isothermal section of the Zn-Sb-In ternary phase diagram, built the zT map near the β-Zn4Sb3 phase region, and showed that the formation of multiscale microstructures has a profound impact on the electronic and phonon transport properties and phase stability. A high-zT zone was identified near the phase boundary between the two-phase InSb + Zn5Sb4In2 and the three-phase Zn4Sb3 + InSb + Zn5Sb4In2 regions. A sample with a nominal composition of Zn3.8In0.2Sb3 exhibited an ultralow κL of 0.2 (W m-1 K-1), an enhanced PF of 1.75 (mW m-1 K-2), and a remarkable zT value of 1.8 at 698 K. These state-of-the-art thermoelectric properties were attributed to the simultaneous enhancement in phonon scattering and the carrier energy-filtering effect in a unique hierarchical microstructure, in which InSb nanoprecipitates are dispersed in Zn5Sb4In2 coarse grains, and the latter are embedded in the host matrix In-Zn4Sb3. These results opened an avenue for environmentally friendly cost-effective midtemperature thermoelectric materials.
AB - Zn4Sb3-based compounds constitute a lead-free material family with a best thermoelectric figure of merit (zT) in the midtemperature range. Unlike being a stoichiometric compound, the mutual solubility of Zn and Sb elicits rich microstructures and the structural instability of Zn4Sb3. The solubility limit and neighboring phase relations are crucial for the delicate balance between the thermoelectric performance and phase stability of Zn4Sb3. In this work, we constructed the isothermal section of the Zn-Sb-In ternary phase diagram, built the zT map near the β-Zn4Sb3 phase region, and showed that the formation of multiscale microstructures has a profound impact on the electronic and phonon transport properties and phase stability. A high-zT zone was identified near the phase boundary between the two-phase InSb + Zn5Sb4In2 and the three-phase Zn4Sb3 + InSb + Zn5Sb4In2 regions. A sample with a nominal composition of Zn3.8In0.2Sb3 exhibited an ultralow κL of 0.2 (W m-1 K-1), an enhanced PF of 1.75 (mW m-1 K-2), and a remarkable zT value of 1.8 at 698 K. These state-of-the-art thermoelectric properties were attributed to the simultaneous enhancement in phonon scattering and the carrier energy-filtering effect in a unique hierarchical microstructure, in which InSb nanoprecipitates are dispersed in Zn5Sb4In2 coarse grains, and the latter are embedded in the host matrix In-Zn4Sb3. These results opened an avenue for environmentally friendly cost-effective midtemperature thermoelectric materials.
UR - http://hdl.handle.net/10754/659498
UR - https://pubs.acs.org/doi/10.1021/acsaem.9b01531
UR - http://www.scopus.com/inward/record.url?scp=85073166722&partnerID=8YFLogxK
U2 - 10.1021/acsaem.9b01531
DO - 10.1021/acsaem.9b01531
M3 - Article
SN - 2574-0962
VL - 2
SP - 7564
EP - 7571
JO - ACS Applied Energy Materials
JF - ACS Applied Energy Materials
IS - 10
ER -