Thermoelectric efficiency

Samarium has a bright silver luster and is reasonably stable in air. Three crystal modifications of the metal exist, with transformations at 734 and 922oC. The metal ignites in air at about ISOoC. The sulfide has excellent high-temperature stability and good thermoelectric efficiencies up to llOOoC. 

After this, there was a long period of quiescence, broken by a new bout of innovation in the 1990s. Thermoelectric efficiency depends on physical parameters through a dimensionless of merit, ZT, where Z = S lKp. Here S is the Seebeck... 

Several strategies based on novel device architectures have been developed in an effort to improve overall thermoelectric efficiency, one of the most promising of which is the use of quantum well superlattices. In certain superlattice systems, the electrical conductivity through the wells is dramatically increased due to an increase in the density of electronic states in the two dimensional system. At the same time, in a layered structure such as a superlattice, thermal conductivity is decreased due to enhanced phonon scattering at interfaces. Hicks, et al. have shown that a significant increase in the figure of merit can be achieved using quantum well superlattices synthesized by molecular beam epitaxy (4). 

In this paper, we investigate the use of EC-ALE to synthesize thin films of CoSb phases with an aim toward the production of layered structures of these materials for use in thermoelectric applications. If successful, such an approach will lead to thin films with enhanced thermoelectric efficiencies, while at the same time keeping the production cost of the device low. 

The second practical challenge in phononic transport rises from heat-to-electricity conversion technology. Here, in order to develop efficient thermoelectric materials, one seeks structures with ultralow heat conductivity in conjunction with high electrical conductivity and a high Seebeck coefficient. Ultralow conductivity was manifested in disordered-layered WSe2 crystals [13], probably due to the localization of lattice vibrations. Si nanowires show enhanced thermoelectric efficiency compared... 

Abzianidze, T., G. Karumidze, L. Kekelidze, E. Tabatadze, L. Shengelia, G. Bokuchava, and B. Shirokov. 2004. Possibilities of rising in the radiation stability and thermoelectric efficiency of boron carbide. In Proceedings of the 16th International Conference on Physics Radiation Phenomena and Radiative Materials Science, Kharkov, Ukraine, p. 88. 

G.-H. Kim, L. Shao, K. Zhang, K. P. Pipe, Engineered Doping of Organic Semiconductors for Enhanced Thermoelectric Efficiency. Nat. Mater. 2013, 12, 719-723. 

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