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Mechanism of Rare Earth Incorporation and Crystal Growth of Rare Earth Containing Type-I Clathrates.

ABSTRACT: Type-I clathrates possess extremely low thermal conductivities, a property that makes them promising materials for thermoelectric applications. The incorporation of cerium into one such clathrate has recently been shown to lead to a drastic enhancement of the thermopower, another property determining the thermoelectric efficiency. Here we explore the mechanism of the incorporation of rare earth elements into type-I clathrates. Our investigation of the crystal growth and the composition of the phase Ba_8-x RE _x TM _y Si_46-y (RE = rare earth element; TM = Au, Pd, Pt) reveals that the RE content x is mainly governed by two factors, the free cage space and the electron balance.

SUBMITTER: Prokofiev A

PROVIDER: S-EPMC4718404 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Mechanism of Rare Earth Incorporation and Crystal Growth of Rare Earth Containing Type-I Clathrates.

Prokofiev Andrey A Svagera Robert R Waas Monika M Weil Matthias M Bernardi Johannes J Paschen Silke S

Crystal growth & design 20151202 1

Type-I clathrates possess extremely low thermal conductivities, a property that makes them promising materials for thermoelectric applications. The incorporation of cerium into one such clathrate has recently been shown to lead to a drastic enhancement of the thermopower, another property determining the thermoelectric efficiency. Here we explore the mechanism of the incorporation of rare earth elements into type-I clathrates. Our investigation of the crystal growth and the composition of the ph ...[more]

PMID: 26823658

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