Low lattice thermal conductivity in Pb₅Bi₆Se₁₄, Pb₃Bi₂S₆, and PbBi₂S₄: promising thermoelectric materials in the cannizzarite, lillianite, and galenobismuthite homologous series

Abstract

We demonstrate a notable power factor and an extremely low lattice thermal conductivity in Pb5Bi6Se14 (cannizzarite homolog), Pb3Bi2S6 (lillianite homolog), and PbBi2S4 (galenobismuthite homolog).

Hierarchical Architecturing for Layered Thermoelectric Sulfides and Chalcogenides

“…Figure 4 shows scanning electron microscopy (SEM) micrographs of the fractured section of sintered compacts of Ti 1.008 S 2 [29], [LaS] 1.20 CrS 2 [32], and Pb 5 Bi 6 Se 14 [34] that were fractured parallel to the pressure direction. The micrographs reveal a dense structure and well-organized microtexture, indicating that the pressurized sintering promotes densification and grain orientation.…”

“…The micrographs reveal a dense structure and well-organized microtexture, indicating that the pressurized sintering promotes densification and grain orientation. The XRD patterns show that the crystalline c -axis is preferentially oriented along the pressing (out-of-plane) direction [29,32,34]. A centrifugal heating technique also provides the dense samples with highly oriented microtexture [56].…”

“…Scanning electron micrographs of the fractured section of sintered compacts of ( a ) Ti 1.008 S 2 [29]; ( b ) [LaS] 1.20 CrS 2 [32]; and ( c ) Pb 5 Bi 6 Se 14 [34]. …”

“…Crystal structures of the thermoelectric sulfides and chalcogenides addressed in this article: ( a ) TiS 2 [29,30]; ( b ) [LaS] 1.14 NbS 2 [31,32]; ( c ) Pb 5 Bi 6 Se 14 [33,34]; ( d ) SnSe [35]; and ( e ) Cu 12 Sb 4 S 13 [36,37]. Sizes of atoms in this figure are arbitrary.…”

The Crystal Structures of Pb5Sb4S11 (Boulangerite) – A Phase Transition Explains Seemingly Contradictory Structure Models

“…[3][4][5][6][7][8] For instance, Ag-doped SnS reaches thermoelectric Figure of merit ZT up to 0.6 at 900 K, [9] while PbBi 2 S 4 (galenobismutite) and Pb 3 Bi 2 S 6 (lillianite) reach about 0.3 at 750 K. The ZT value of Pb 5 Bi 6 Se 14 even reaches 0.5 at 700 K. [10] The crystal chemistry of chain-like structures of lead antimony sulfides has been discussed in detail by Skowron & Brown and Makovicky. [11,12] …”