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Optimization of thermoelectric performance of SrSi2-based alloys via the modification in band structure and phonon-point-defect scattering.

ABSTRACT: Thermoelectric properties of alkaline-earth-metal disilicides are strongly dependent on their electronic band structure in the vicinity of the Fermi level. In particular, the strontium disilicide, SrSi2 with a narrow band gap of about few tens of meV is composed of non-toxic, naturally abundant elements, and its thermoelectric properties are very sensitive to the substitution/alloying with third elements. In this article, we summarize the thermoelectric performance of substituted and Sr-deficient/Sr-rich SrSi2 alloys to realize the high thermoelectric figure-of-merit (ZT) for practical applications in the electronic and thermoelectric aspects, and also to explore the alternative routes to further improve its ZT value.

SUBMITTER: Kuo YK

PROVIDER: S-EPMC4243697 | biostudies-other | 2014

REPOSITORIES: biostudies-other

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Optimization of thermoelectric performance of SrSi2-based alloys via the modification in band structure and phonon-point-defect scattering.

Kuo Yung-Kang YK Ramachandran Balakrishnan B Lue Chin-Shan CS

Frontiers in chemistry 20141125

Thermoelectric properties of alkaline-earth-metal disilicides are strongly dependent on their electronic band structure in the vicinity of the Fermi level. In particular, the strontium disilicide, SrSi2 with a narrow band gap of about few tens of meV is composed of non-toxic, naturally abundant elements, and its thermoelectric properties are very sensitive to the substitution/alloying with third elements. In this article, we summarize the thermoelectric performance of substituted and Sr-deficien ...[more]

PMID: 25505784

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