Thermoelectric properties and nonstoichiometry of GaGeTe

Journal Article · Sat Sep 15 00:00:00 EDT 2012 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/J.JSSC.2012.03.030· OSTI ID:22149798

Kucek, V.; Benes, L.; Lostak, P. ^[1]; Vlcek, M. ^[2]

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1. Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice (Czech Republic)
2. Joint Laboratory of Solid State Chemistry of IMC AS CR and University of Pardubice, Studentska 84, 53210, Pardubice (Czech Republic)

Polycrystalline samples of composition Ga{sub 1+x}Ge{sub 1-x}Te (x=-0.03 Division-Sign 0.07) and GaGeTe{sub 1-y} (y=-0.02 Division-Sign 0.02) were synthesized from elements of 5 N purity using a solid state reaction. The products of synthesis were identified by X-ray diffraction; phase purity and microstructure were examined by EDX/SEM. Samples for measurement of transport properties were prepared using hot-pressing. They were characterized by measurement of electrical conductivity, the Hall coefficient, and the Seebeck coefficient over a temperature range 80-480 K and of thermal conductivity over a temperature range 300-580 K. All samples show p-type conductivity. We discuss the influence of stoichiometry on the phase purity of the samples and on free carrier concentration. The investigation of thermoelectric properties shows that the power factor of these samples is low compared to state-of-the-art materials at room temperature but increases distinctly with temperature. - Graphical abstract: Structure and preparation of GaGeTe. Electrical conductivity {sigma}, the Hall coefficient R{sub H}, the Seebeck coefficient S and thermal conductivity {kappa} as a function of temperature for the Ga{sub 1.01}Ge{sub 0.99}Te{sub 0.99} sample. Highlights: Black-Right-Pointing-Pointer We explore thermoelectric and transport properties of Ga{sub 1+x}Ge{sub 1-x}Te and GaGeTe{sub 1-y}. Black-Right-Pointing-Pointer GaGeTe is p-type degenerate semiconductor; the hole concentration increase with x and y. Black-Right-Pointing-Pointer Maximum power factor {sigma}S{sup 2}=3.6 Multiplication-Sign 10{sup -4} Wm{sup -1} K{sup -2} at 475 K.

• OSTI ID: 22149798
• Journal Information: Journal of Solid State Chemistry, Vol. 193; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ELECTRIC CONDUCTIVITY
GALLIUM
GERMANIUM
IMPURITIES
MICROSTRUCTURE
POLYCRYSTALS
POWER FACTOR
SCANNING ELECTRON MICROSCOPY
SEMICONDUCTOR MATERIALS
SOLIDS
SYNTHESIS
TEMPERATURE DEPENDENCE
THERMAL CONDUCTIVITY
THERMOELECTRIC PROPERTIES
X-RAY DIFFRACTION