The present invention is generally directed to nanocomposite thermoelectric materials that exhibit enhanced thermoelectric properties. The nanocomposite materials include two or more components, with at least one of the components forming nanosized structures within the composite material. The components are chosen such that thermal conductivity of the composite is decreased without substantially diminishing the composite’s electrical conductivity. Suitable component materials exhibit similar electronic band structures. For example, a band-edge gap between at least one of a conduction band or a valence band of one component material and a corresponding band of the other component material at interfaces between the components can be less than about 5kBT, wherein kB is the Boltzman constant and T is an average temperature of said nanocomposite composition.

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Nanocomposites with high thermoelectric figures of merit

Thermoelectric materials with high figures of merit, ZT values, are disclosed. In many instances, such materials include nano-sized domains (e.g., nanocrystalline), which are hypothesized to help increase the ZT value of the material (e.g., by increasing phonon scattering due to interfaces at grain boundaries or grain/inclusion boundaries). The ZT value of such materials can be greater than about 1, 1.2, 1.4, 1.5, 1.8, 2 and even higher. Such materials can be manufactured from a thermoelectric starting material by generating nanoparticles therefrom, or mechanically alloyed nanoparticles from elements which can be subsequently consolidated (e.g., via direct current induced hot press) into a new bulk material. Non-limiting examples of starting materials include bismuth, lead, and/or silicon-based materials, which can be alloyed, elemental, and/or doped. Various compositions and methods relating to aspects of nanostructured thermoelectric materials (e.g., modulation doping) are further disclosed.

Methods for high figure-of-merit in nanostructured thermoelectric materials

A method for separating a metal from a composition including the metal involves forming an electrolytic cell in which the anode comprises a composition including the metal. The electrolyte is an ionic liquid. A sufficient potential difference is applied between the anode and the cathode to cause the metal to transfer from the anode to the cathode and to be deposited thereon.

Process for separating metals

The present invention provides an indium-doped Co4Sb12 skutterudite composition in which some Co on the cubic lattice structure may be replaced with one or more members of the group consisting of Fe, Ni, Ru, Rh, Pd, Ir and Pt; some Sb on the planar rings may be replaced by one or more members of the group consisting of Si, Ga, Ge and Sn; and a second dopant atom is selected from a member of the group consisting of Ca, Sc, Zn, Sr, Y, Pd, Ag, Cd, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The composition is useful as a thermoelectric material. In preferred embodiments, the composition has a figure of merit greater than 1.0. The present invention also provides a process for the production of the composition, and thermoelectric devices using the composition.

High performance thermoelectric materials and their method of preparation

The present invention provides a thermoelectric conversion device having high thermoelectric conversion performance. In this device, electrodes are arranged so that electric current flows in an interlayer direction of a layered substance, unlike the arrangements derived from common knowledge in the art. In the thermoelectric conversion device according to the present invention, a thermoelectric-conversion film is obtained through epitaxial growth and formed by arranging an electrically conducting layer and an electrically insulating layer alternately; the electrically conducting layer has an octahedral crystal structure in which a transition metal atom M is positioned at its center and oxygen atoms are positioned at its vertexes; and the electrically insulating layer includes a metal element or a crystalline metal oxide. The c axis of the layered substance made of the electrically conducting layer and the electrically insulating layer is parallel to an in-plane direction of the substrate, and a pair of electrodes are arranged so that electric current flows along the c axis.

Thermoelectric conversion device, and cooling method and power generating method using the device

PROBLEM TO BE SOLVED: To provide a filledskutterudite-family thermoelectric conversion material that does not contain any lead, is manufactured by a simple process where grinding and hot press are eliminated, shows high thermoelectric characteristics in a medium-temperature region of 700 K or less, and has excellent thermoelectric conversion efficiency. SOLUTION: Current flows in an in-plain direction being vertical to the quenching direction for obtaining a material where a metal mass obtained by allowing the thermoelectric conversion material to be subjected to fluxing and quenching is heat-treated. In this case, the thermoelectric conversion material is mainly composed of a filledskutterudite compound. In the thermoelectric conversion material, the main part of the material is shown by a composition expression LnXT4Pn12. In this case, Ln is at least one kind selected from a group of La, Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yd, Lu, Th, and U, T is at least one kind this selected from a group of Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, and Pt, Pn is at least one kind selected from a group of P, As, Sb, S, Se, and Te, and X is equal to or more than 0.2 and equal to or less than 1.

Thermoelectric conversion material and element

A waste treatment apparatus treats radioactive contaminated waste from a nuclear fuel material handling facility to decontaminate the radioactive contaminated waste by using an electrolytic molten salt, and reuses the electrolytic molten salt so that any effluents are not produced. Radioactive contaminated waste ( 10 ) from a nuclear fuel material handling facility is subjected to electrolysis by a molten salt electrolysis unit ( 20 ) to decontaminate the waste ( 10 ). The used salt ( 16 ) used for decontaminating the waste ( 10 ) is filtered to separate nuclear fuel materials ( 19 ) from the used salt ( 16 ). The filtered salt ( 18 ) is reused by the molten salt electrolysis unit ( 20 ). The salt adhering to the decontaminated waste ( 12 ) is recovered by an evaporating unit ( 59 ), and the recovered salt ( 15 ) is reused by the molten salt electrolysis unit ( 20 ).

Method of treating waste from nuclear fuel handling facility and apparatus for carrying out the same

Method and apparatus of treating waste from nuclear fuel handling facility

PROBLEM TO BE SOLVED: To provide a thermoelectric conversion module which uses a thermoelectric conversion element usable at 400 deg.C or above. SOLUTION: The thermoelectric conversion module comprises a p-type thermoelectric conversion element main body (11) and an n-type thermoelectric conversion element main body (13), which are so provided as to constitute a first plane on a high-temperature side and a second plane on a low-temperature side while connected in series (to face each other) using electrode members (13 and 14). The p-type thermoelectric conversion element main body (11) comprises a p-type silicon semiconductor while the n-type thermoelectric conversion element main body (12) comprises an n-type silicon semiconductor. The electrode members (13 and 14) comprise a silver electrode material.

Thermoelectric conversion module and heat exchanger using it

PROBLEM TO BE SOLVED: To provide a thermoelectric conversion material having a low coeffi cient of thermal conductivity, a high thermoelectric conversion efficiency, and low toxicity. SOLUTION: This thermoelectric conversion material has a composition expressed by the following chemical formula (1): NaαMXAYO4-Z, where, M and A respectively represent one or more kinds of alkali metallic elements 4 selected from among K, Rb, and Cs and one or more kinds of metallic elements selected from among Co, Fe, Ni and Cu and the mol rations α, X, Y, and Z respectively represent numerical values meeting 0<α<1.2, 0.1<=X<=1, 0.7<=α+X<=1.2, 0<Y, and 0<=Z.

Naruhito Kondo

Papers

Thermoelectric conversion material and element

Method of treating waste from nuclear fuel handling facility and apparatus for carrying out the same

Method and apparatus of treating waste from nuclear fuel handling facility

Thermoelectric conversion module and heat exchanger using it

Thermoelectric conversion material, thermoelectric conversion element, thermal battery, and cooler