Technology of production of high effective thermoelectric materials on the base nanodimensional films of CoSb3 skutterudite

Keywords
New substances and materials

Description
Production of nanoscaled skutterudite CoSb3 –based film as thermoelectric material with high attributes of thermoelectric properties

Innovative aspect and main advantages:
In spite of active attempts to get material with the high value of ZT nowaday thermoelectric elements which in majorities are synthesized by the methods of powder metallurgy have ZT which does not exceed 1. In the nanodimensional film state ZT, as theoretical calculations show, can have value ≥ 2. It is explained that at transition to nanodimensions the electron-phonon interaction decreases and a phonon subsystem, being adiabatically isolated, does not almost accept participating in the transfer of heat from a heater to the cooler. Therefore nanostructuring of thermoelectric materials is effective technology to achieve a high ZT due to achievement of low thermal conductivity.
It is suggested to use the nanodimensional CoSb3 –based skutterudite film as thermoelectric material with high-performance thermoelectric properties. A lattice thermal conductivity can be considerably reduced due to decrease of size of grains that results in additional scattering of phonons on the grain boundaries, and also presence of pores in films. One of the special properties of skutterudite compounds there is also possibility of decrease of lattice thermal conductivity when small in size atoms fill pores in the crystalline structure of skutterudite. Alloying atoms (filler of pores), for example, the atoms of elements of Ba, Yb, Tl, Ce, La, at resonance frequency additionally scatter heat, what is carried by phonons, that results in the lower thermal conductivity of film. Due to it thermoelectric efficiency of ZT can attain the value more than 1,4.

Problem solved:
Thermoelectrics is priority direction of development of science and technique based on the direct conversion of thermal energy into electric. Absence of moing parts and possibility of functioning in extreme conditions provide with thermoelectric energy sources a high reliability and practically unlimited resource of work. The special advantage is using the thermal energy that is lost. For this reason such sources are founded wide application in space, in a military technique and in the way of life.

Development status:
Concept or theoretical stage, not yet proven

Potential customers, markets:
Space field, military technics, life