Composition and properties of compounds in the PbSe-Bi2Se3 system

Topological metal behavior in GeBi2Te4single crystals

“…[19][20][21][22]30 The systems were found to have either an A or B site deficiency, 23 or antisite disorder. 22 Both have been reported previously 31,32 and also observed recently by Okamoto et al 26 In the current work, an inspection of the SXPD patterns of GBT confirmed the rhombohedral R3m structure, with lattice constants at room temperature a = 4.3262(1)Å and c = 41.3356(7)Å.…”

“…19,20 GBT belongs to the family of tetradymitelike-layered pseudobinary compounds with a general chemical formula A IV B VI − A V 2 B VI 3 (A IV = Ge, Sn, Pb; A VI = Bi, Sb; B VI = Te, Se). [21][22][23][24] Compounds with such a complex, many-layered structure (up to nine atomic layers per building block) had already been studied mainly due to their thermoelectric properties. [21][22][23][24] Very recently, GBT was claimed to be a 3D TI based on ARPES measurements, 25 albeit with a Dirac point lying below the Fermi energy ( −0.2 eV).…”

“…[21][22][23][24] Compounds with such a complex, many-layered structure (up to nine atomic layers per building block) had already been studied mainly due to their thermoelectric properties. [21][22][23][24] Very recently, GBT was claimed to be a 3D TI based on ARPES measurements, 25 albeit with a Dirac point lying below the Fermi energy ( −0.2 eV). This is in contrast with first principle calculations, 25,26 which place the Dirac point inside the band gap, and a resolution of this point is imperative.…”

Hierarchical Architecturing for Layered Thermoelectric Sulfides and Chalcogenides

“…The two layers are stacked alternately along the c -axis, resulting in a three-dimensional structure with varying thicknesses that form different members in the homology. The thermoelectric properties of homologous compounds can be tuned by modifying the size and shape of the structural module(s); therefore, the homologous compounds are good platforms for developing new thermoelectric materials [34,94,98,99,100,101,102,103,104,105,106,107,108,109]. …”

“…Another way is to reduce κ lat further by increasing the complexity of the crystal structure using crystal-structural evolution enabled by the homologous series (Figure 9). Table 3 lists the room-temperature thermoelectric properties of three members of the cannizzarite homologous series, Pb 5 Bi 6 Se 14 , Pb 5 Bi 12 Se 23 , and Pb 5 Bi 18 Se 32 [103]. An important result here is that κ lat systematically reduces from 0.72 W·K −1 ·m −1 for Pb 5 Bi 6 Se 14 ( m = 1, n = 1) to 0.49 W·K −1 ·m −1 for Pb 5 Bi 18 Se 32 ( m = 1, n = 3), demonstrating the reduction in κ lat through crystal-structural evolution at the atomic scale.…”