Back to Search
Start Over
Bi4O4Cu1.7Se2.7Cl0.3: Intergrowth of BiOCuSe and Bi2O2Se Stabilized by the Addition of a Third Anion
- Source :
- Journal of the American Chemical Society
- Publication Year :
- 2017
- Publisher :
- American Chemical Society (ACS), 2017.
-
Abstract
- Layered two-anion compounds are of interest for their diverse electronic properties. The modular nature of their layered structures offers opportunities for the construction of complex stackings used to introduce or tune functionality, but the accessible layer combinations are limited by the crystal chemistries of the available anions. We present a layered three-anion material, Bi4O4Cu1.7Se2.7Cl0.3, which adopts a new structure type composed of alternately stacked BiOCuSe and Bi2O2Se-like units. This structure is accessed by inclusion of three chemically distinct anions, which are accommodated by aliovalently substituted Bi2O2Se0.7Cl0.3 blocks coupled to Cu-deficient Bi2O2Cu1.7Se2 blocks, producing a formal charge modulation along the stacking direction. The hypothetical parent phase Bi4O4Cu2Se3 is unstable with respect to its charge-neutral stoichiometric building blocks. The complex layer stacking confers excellent thermal properties upon Bi4O4Cu1.7Se2.7Cl0.3: a room tem-perature thermal conductivity (κ) of 0.4(1) W/mK was measured on a pellet with preferred crystallite orientation along the stacking axis, with perpendicular measurement indicating it is also highly anisotropic. This κ value lies in the ultra-low regime and is smaller than that of both BiOCuSe and Bi2O2Se. Bi4O4Cu1.7Se2.7Cl0.3 behaves like a charge-balanced semiconductor with a narrow band gap. The chemical diversity offered by the additional anion allows the integration of two common structural units in a single phase by the simultaneous and coupled creation of charge-balancing defects in each of the units.
- Subjects :
- Chemistry
Stacking
Formal charge
02 engineering and technology
General Chemistry
010402 general chemistry
021001 nanoscience & nanotechnology
01 natural sciences
Biochemistry
Catalysis
0104 chemical sciences
Ion
Crystal
Crystallography
Colloid and Surface Chemistry
Thermal conductivity
Phase (matter)
0210 nano-technology
Layer (electronics)
Stoichiometry
Subjects
Details
- ISSN :
- 15205126 and 00027863
- Volume :
- 139
- Database :
- OpenAIRE
- Journal :
- Journal of the American Chemical Society
- Accession number :
- edsair.doi.dedup.....2860d095be024cb137af816af4dc9b95
- Full Text :
- https://doi.org/10.1021/jacs.7b06168