A thermoelectric material element includes: a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode. During the operation, the thermoelectric material portion includes a first temperature region having a first temperature, and a second temperature region having a second temperature lower than the first temperature of the first temperature region. A ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.

A thermoelectric material element includes: a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode. During the operation, the thermoelectric material portion includes a first temperature region having a first temperature, and a second temperature region having a second temperature lower than the first temperature of the first temperature region. A ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.

A thermoelectric composition is provided that includes a nanocomposite comprising a copper selenide (Cu.sub.2Se) matrix having a plurality of nanoinclusions comprising copper metal selenide (CuMSe.sub.2) distributed therein. M may be selected from the group consisting of: indium (In), aluminum (Al), gallium (Ga), antimony (Sb), bismuth (Bi), and combinations thereof. The thermoelectric composition has an average figure of merit (ZT) of greater than or equal to about 1.5 at a temperature of less than or equal to about 850K (about 577° C.). Methods of making such a thermoelectric nanocomposite material by a sequential solid-state transformation of a CuSe.sub.2 precursor are also provided.

Provided herein is a thermoelectric element that includes a cold end, a hot end, and a p-type or n-type material having a length between the hot end and the cold end. The p-type or n-type material has an intrinsic Seebeck coefficient (S), an electrical resistivity (ρ), and a thermal conductivity (λ). Each of two or more of S, ρ, and λ generally increases along the length from the cold end to the hot end. The thermoelectric element may be provided in single-stage thermoelectric devices providing enhanced maximum temperature differences. The single-stage thermoelectric devices maybe combined with one another to provide multi-stage thermoelectric devices with even further enhanced maximum temperature differences.

Provided herein is a thermoelectric element that includes a cold end, a hot end, and a p-type or n-type material having a length between the hot end and the cold end. The p-type or n-type material has an intrinsic Seebeck coefficient (S), an electrical resistivity (ρ), and a thermal conductivity (λ). Each of two or more of S, ρ, and λ generally increases along the length from the cold end to the hot end. The thermoelectric element may be provided in single-stage thermoelectric devices providing enhanced maximum temperature differences. The single-stage thermoelectric devices maybe combined with one another to provide multi-stage thermoelectric devices with even further enhanced maximum temperature differences.

A thermoelectric cooler including a thermoelectric junction and a radiation source. The thermoelectric cooler includes n-type material, p-type material, and an electrical power source. The radiation source emits ionizing radiation that increases electrical conductivity of the n and p type materials. Also detailed is a method of using radiation to reach high coefficient of performance (COP) values with a thermoelectric cooler that includes providing a thermoelectric cooler and a radiation source, with the thermoelectric cooler including an n-type material, p-type material, an electrical power source, and emitting ionizing radiation with the radiation source to increase the electrical conductivity which strips electrons from the n-type material, the p-type material, or both the n-type material and p-type material from their nuclei with the electrons then free to move within the material.

Composite nanoparticle compositions and associated nanoparticle assemblies are described herein which, in some embodiments, exhibit enhancements to one or more thermoelectric properties including increases in electrical conductivity and/or Seebeck coefficient and/or decreases in thermal conductivity. In one aspect, a composite nanoparticle composition comprises a semiconductor nanoparticle including a front face and a back face and sidewalls extending between the front and back faces. Metallic nanoparticles are bonded to at least one of the sidewalls establishing a metal-semiconductor junction.

Disclosed is a composition for forming a thermoelectric film, the composition comprising an edge-oxidized graphene oxide, wherein the edge-oxidized graphene oxide is dispersed in a thermoelectric material.

Composite nanoparticle compositions and associated nanoparticle assemblies exhibit enhancements to one or more thermoelectric properties including increases in electrical conductivity and/or Seebeck coefficient and/or decreases in thermal conductivity. A composite nanoparticle composition comprises a semiconductor nanoparticle including a front face and a back face and sidewalls extending between the front and back faces. Metallic nanoparticles are bonded to at least one of the sidewalls establishing a metal-semiconductor junction.

Composite nanoparticle compositions and associated nanoparticle assemblies exhibit enhancements to one or more thermoelectric properties including increases in electrical conductivity and/or Seebeck coefficient and/or decreases in thermal conductivity. A composite nanoparticle composition comprises a semiconductor nanoparticle including a front face and a back face and sidewalls extending between the front and back faces. Metallic nanoparticles are bonded to at least one of the sidewalls establishing a metal-semiconductor junction.