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 00:00:00 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, Vol. 30, Issue 12; Other Information: PBD: Dec 1994; TN: Translated from Neorganicheskie Materialy; 30: No. 12, 1516-1522(1994)
• Country of Publication: United States
• Language: English

Related Subjects

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