Chalcopyrite ZnSnSb₂: A Promising Thermoelectric Material

Abstract

Ternary compounds with a tetragonal chalcopyrite structure, such as CuGaTe 2 , are promising thermoelectric (TE) materials. It has been demonstrated in various chalcopyrite systems, including compounds with quaternary chalcopyrite-like structures, that the lattice parameter ratio, c/a, being exactly 2.00 to have a pseudocubic structure is key to increase the degeneracy at the valence band edge and ultimately achieve high TE performance. Considering the fact that ZnSnSb 2 with a chalcopyrite structure is reported to have c/a close to 2.00, it is expected to have multiple valence bands leading to a high p-type zT. However, there are no complete investigations on the high temperature TE properties of ZnSnSb 2 mainly because of the difficulty of obtaining a single-phase ZnSnSb 2 . In the present study, pure ZnSnSb 2 samples with no impurities are synthesized successfully using a Sn flux-based method and TE properties are characterized up to 585 K. Transport properties and thermal analysis indicate that the structure of ZnSnSb 2 remains chalcopyrite with no order− disorder transition and clearly show that ZnSnSb 2 can be made to exhibit a high zT in the low-to-mid temperature range through further optimization.

High-Throughput Screening for Advanced Thermoelectric Materials: Diamond-Like ABX2 Compounds

“…Despite the high PFs, pnictides are comparable with the chalcogenide counterparts in ZT max because of the cancellation from enhanced κ e s and κ L s. In Figure c, 12 compounds with ZT > 0.6 are labeled. CuInTe 2 and AgGaTe 2 have been experimentally confirmed to be high-performance p-type TE materials, and their experiment ZT values at 700 K are 0.59 and 0.5, respectively, which are consistent with our theoretical results (0.66 and 0.67). , Nomura et al recently reported that ZnSnSb 2 is a promising TE material . The other compounds, predicted TE materials CdSnSb 2 , AgInS 2 , AgGaSe 2 , ZnCdTe 2 , and LiInTe 2 , have been little studied in this context experimentally, but based on the results above, they are promising TE materials.…”

“…17,19 Nomura et al recently reported that ZnSnSb 2 is a promising TE material. 32 The other compounds, predicted TE materials CdSnSb 2 , AgInS 2 , AgGaSe 2 , ZnCdTe 2 , and LiInTe 2 , have been little studied in this context experimentally, but based on the results above, they are promising TE materials. By the same method, the predicted maximum ZT values of n-type ABX 2 compounds at 700 K are shown in Figure 4d, and 12 compounds with ZT > 0.6 are labeled.…”

“…S-, Se-, and Te-based chalcogenide diamond-like compounds have been widely reported. Compounds based on other anions, such as P-, As-, and Sb-based compounds, have been less studied as TE materials, − although many of these have been studied as photovoltaic materials, with findings of reasonable semiconducting properties, such as charge carrier transport. − Here we use the HTP calculations, recently done for chalcogenides, to study the TE properties of ternary ABX 2 (A = IA, IIA, IIIA, VA, IB, and IIB; B = IA, IIIA, IVA, VA, and IIB, VB, VIII; X = IIIA, VA, VIA, and VIIA) compounds with diamond-like structures.…”

Realizing High Thermoelectric Performance in the ZnTe-Alloyed CuGaTe2 through Band Engineering

“…In the semiconductor, S , σ, and κ e are always coupled with each other, and lattice thermal conductivity κ L is the relatively independent parameter and is affected by the phonon scattering efficiency. The majority strategies to improve the ZT are not only to improve the thermoelectric power factor ( S 2 σ) through carrier concentration optimization, band structure engineering, and energy filtering effect but also to lower the κ L by alloying, introducing alloying, dislocations, nanostructure, low dimensions, strong anharmonicity, and low sound speed to suppress the phonon propagation. − Point defect scattering is the most effective and simplest way to reduce κ L in the thermoelectric materials, including vacancy, substitutional, and interstitial defects.…”

Phase Boundary Mapping of Tin‐Doped ZnSb Reveals Thermodynamic Route to High Thermoelectric Efficiency

“…The impurity phase Zn 4 Sb 3 is a well-known p-type thermoelectric phase, [15,16] while ZnSnSb 2 has only a small window of stability. [17] The two different liquid phases that appear in the 400 °C phase diagram transform primarily into crystalline Sn and SnSb when quenched to room temperature.…”