Synthesis, characterisation and thermoelectric properties of the oxytelluride Bi{sub 2}O{sub 2}Te

Journal Article · Sun Mar 15 04:00:00 EDT 2015 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2015.02.026· OSTI ID:22475657

Luu, Son D.N. ^[1]; Vaqueiro, Paz ^[2]

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1. Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom)
2. Department of Chemistry, University of Reading, Whiteknights, Reading RG6 6AD (United Kingdom)

Bi{sub 2}O{sub 2}Te was synthesised from a stoichiometric mixture of Bi, Bi{sub 2}O{sub 3} and Te by a solid state reaction. Analysis of powder X-ray diffraction data indicates that this material crystallises in the anti-ThCr{sub 2}Si{sub 2} structure type (space group I4/mmm), with lattice parameters a=3.98025(4) and c=12.70391(16) Å. The electrical and thermal transport properties of Bi{sub 2}O{sub 2}Te were investigated as a function of temperature over the temperature range 300≤T (K)≤665. These measurements indicate that Bi{sub 2}O{sub 2}Te is an n-type semiconductor, with a band gap of 0.23 eV. The thermal conductivity of Bi{sub 2}O{sub 2}Te is remarkably low for a crystalline material, with a value of only 0.91 W m{sup −1} K{sup −1} at room temperature. - Graphical abstract: Bi{sub 2}O{sub 2}Te, which crystallises in the anti-ThCr{sub 2}Si{sub 2} structure type, is an n-type semiconductor with a remarkably low thermal conductivity. - Highlights: • Bi{sub 2}O{sub 2}Te crystallises in the anti-ThCr{sub 2}Si{sub 2} structure type. • Bi{sub 2}O{sub 2}Te is an n-type semiconductor, with a band gap of 0.23 eV. • The thermal conductivity of Bi{sub 2}O{sub 2}Te approaches values found for amorphous solids. • The thermoelectric figure of merit of undoped Bi{sub 2}O{sub 2}Te reaches 0.13 at 573 K.

• OSTI ID: 22475657
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Vol. 226; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
BISMUTH OXIDES
BISMUTH TELLURIDES
ELECTRIC CONDUCTIVITY
LATTICE PARAMETERS
MIXTURES
N-TYPE CONDUCTORS
POWDERS
SOLIDS
SYNTHESIS
TEMPERATURE DEPENDENCE
TETRAGONAL LATTICES
THERMAL CONDUCTIVITY
THERMOELECTRIC MATERIALS
THERMOELECTRIC PROPERTIES
X-RAY DIFFRACTION