Antimony telluride is an
inorganic compound with the
chemical formula Sb2Te3. As is true of other pnictogen chalcogenide layered materials, it is a grey
crystalline solid with layered structure. Layers consist of two atomic sheets of antimony and three atomic sheets of
tellurium and are held together by weak
van der Waals forces. Sb2Te3 is a narrow-gap semiconductor with a
band gap 0.21 eV; it is also a
topological insulator, and thus exhibits thickness-dependent physical properties.[1]
Crystalline structure
Sb2Te3 has a rhombohedral crystalline structure.[8] The crystalline material comprises atoms covalently bonded to form 5 atom thick sheets (in order: Te-Sb-Te-Sb-Te), with sheets held together by van der Waals attraction. Due to its layered structure and weak inter-layer forces, bulk antimony telluride may be mechanically exfoliated to isolate single sheets.
Synthesis
Although antimony telluride is a naturally occurring compound, select stoichiometric compounds may be formed by the reaction of
antimony with
tellurium at 500–900 °C.[3]
Doping Sb2Te3 with iron introduces multiple Fermi pockets, in contrast to the single frequency detected for pure Sb2Te3, and results in reduced carrier density and mobility.[9]
^Yáñez-Limón, J. M.; González-Hernández, J.; Alvarado-Gil, J. J.; Delgadillo, I.; Vargas, H. (1995). "Thermal and electrical properties of the Ge:Sb:Te system by photoacoustic and Hall measurements". Physical Review B. 52 (23): 16321–16324.
Bibcode:
1995PhRvB..5216321Y.
doi:
10.1103/PhysRevB.52.16321.
PMID9981020.
^Kim, Won-Sa (1997). "Solid state phase equilibria in the Pt–Sb–Te system". Journal of Alloys and Compounds. 252 (1–2): 166–171.
doi:
10.1016/S0925-8388(96)02709-0.