Ternary Chalcogenides GeSb₂Se₃ and Ge₃Sb₄Se₇ Containing a _∞¹[Sb₂Se₂]^2– 1D Chain and a 2D Structure Related to SnSe

Abstract

Ternary chalcogenides, GeSb2Se3 and Ge3Sb4Se7, were synthesized and characterized. These chalcogenides are the first ternary selenides in a ternary Ge–Sb–Se system that feature a layer structure related to black phosphorus and SnSe-type structures. Both compounds contain a ∞ 1[Sb2Se2]2– unit with Sb+ cations in a zigzag Sb–Sb chain structure, and Sb3+ cations in a distorted NaCl100-type of ∞ 1[Ge n–2Sb2Se n ]2+ unit (n = 4, 5). These materials exhibit n-type semiconducting properties with thermal conductivity significantly lower than that of GeSe and Sb2Se3, which could be correlated to the 1D Sb+ chain and disordered sites with different Ge/Sb compositions. It is anticipated that these newly discovered ternary chalcogenides may provide unique properties with enhanced thermoelectric properties.

Synthesis and Characterization of New Multinary Selenides A10B18Se37 (A=Sn/Pb; B=In/Sb/Bi)

“…Seebeck coefficients in 300 ~773 K remain in negative values of about À 190 to À 250 μV/K, indicating n-type semiconducting behavior (Figure 4b). The observed values are about 1/3 compared to the value from Sn 4 In 5 Sb 9 Se 25 and Sn 6.13 Pb 1.87 In 5.00 Sb 10.12 Bi 2.88 Se 35 and comparable with those of some ternary and quaternary selenides such as GeSb 2 Se 3 , [48] Sn 4 Bi 10 Se 19 , [43][44] Pb 7 Bi 4 Se 13 , [29][30] Pb 6 Bi 2 Se 9 , [45] In 0.2 Sn 6 Bi 1.8 Se 9 , [36] and Pb 4 In x M 6 À x Se 13 (M=Sb, Bi). [49] The reduced Seebeck coefficient can be attributed to the increase in electric conductivity with the effect of heavy element substitution.…”

Synthesis, Crystal Structure, and Physical Properties of BaSnS2

“…Metal chalcogenides continue to be investigated for diverse applications of interest, including nonlinear optics, [ 1 ] thermoelectrics, [ 2,3 ] superconductivity, [ 4 ] and ferroelectrics. [ 5 ] More recently, the synthesis and physical properties of ternary [ 6,7 ] and quaternary [ 8–11 ] chalcogenides have been of intense interest, not only due to an interest in their fundamental properties but also for applied research toward energy‐related applications. [ 12–16 ] For certain materials, the electrical properties can be modified by a variation in stoichiometry, [ 17–19 ] while others display transport properties that are atypical of compositions in this class of materials.…”

Synthesis and Characterization of Multinary Selenides A4B10Se19 (A=Sn, Pb; B=Sb, Bi)

“…[30] The results revealed multinary selenides with complex structures and the compositions of new compounds by stacking known NaCl-type building blocks. A new type of homologous series of Ge nÀ 2 Sb 4 Se n + 2 (n = 4, 5) [31] and [M 2x Se 2xÀ 2 ][M 2yÀ 2 Se 3yÀ 3 ] ((x, y) = (4, 6) and (6, 8)) [32] were synthesized with a new arrangement of building units, indicating that the studies on the homologous series of multinary chalcogenides were successful for creating new compounds with a complex framework. [31][32] In this study, we report the synthesis, structure characterization, and physical properties of A 4 B 10 Se 19 (A = Sn, Pb, B = Sb, Bi).…”