Effect of nonstoichiometry on the electrophysical properties of the layered compounds Ge{sub 3}Bi{sub 2}Te{sub 6} and GeBi{sub 2}Te{sub 4}

Journal Article · Thu Dec 01 04:00:00 EST 1994 · Inorganic Materials

OSTI ID:135583

Shelimova, L E; Karpinskii, O G; Avilov, E S; Kretova, M A; Lubman, C U ^[1]

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1. Baikov Institute of Metallurgy, Moscow (Russian Federation)

The objective of this work was to investigate the effect of deviation from stoichiometry on the electrophysical properties (electrical and thermal conductivity, thermoelectric power, and carrier concentration) of the ternary layered semiconducting compounds Ge{sub 3{plus_minus}{delta}1}Bi{sub 2+{delta}2}Te{sub 6+{delta}3} and Ge{sub 1{plus_minus}{delta}3}, which are promising for use in thermoelectric converters.The electrophysical properties were measured at 300 K. The Ge{sub 1-{delta}1}Bi{sub 2+{delta}3} alloys were studied by powder X-ray diffraction analysis on a DRON UM-1 diffractometer (CoK{sub {alpha}} radiation). It was found that Ge{sub 3{plus_minus}{delta}1} Bi{sub 2+{delta}2}Te{sub 6{plus_minus}{delta}3} is a nonstoichiometric phase with p-type conductivity throughout the {delta}{sub 1}, {delta}{sub 2}, and {delta}{sub 3} ranges examined. Our results suggest that cation vacancies are likely to be the dominant nonstoichiometric defects responsible for the high concentration of holes. The conductivity of Ge{sub 1{plus_minus}{delta}1}Bi{sub 2}Te{sub 4} changes from the p-type in the Ge-deficient alloys to the n-type in the Gerich alloys.

• OSTI ID: 135583
• Journal Information: Inorganic Materials, Journal Name: Inorganic Materials Journal Issue: 12 Vol. 30; ISSN 0020-1685; ISSN INOMAF
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
36 MATERIALS SCIENCE
BISMUTH COMPOUNDS
CARRIER DENSITY
ELECTRIC CONDUCTIVITY
ENERGY SOURCE DEVELOPMENT
GERMANIUM COMPOUNDS
N-TYPE CONDUCTORS
NESDPS Office of Nuclear Energy Space and Defense Power Systems
P-TYPE CONDUCTORS
PHYSICAL PROPERTIES
SEMICONDUCTOR MATERIALS
TELLURIUM COMPOUNDS
THERMAL CONDUCTIVITY
THERMOELECTRIC GENERATORS
THERMOELECTRIC MATERIALS