Thermoelectric properties of Pr3Rh4Sn13-type Yb3Co4Ge13 and Yb3Co4Sn13 compounds

TL;DR

This study reports the crystallographic and thermoelectric properties of Yb3Co4Ge13 and Yb3Co4Sn13 compounds, highlighting their temperature-dependent Seebeck coefficients, electrical resistance, thermal conductivity, and ZT values, with implications for thermoelectric applications.

Contribution

It provides new thermoelectric data for Yb3Co4Ge13 and Yb3Co4Sn13 compounds, including solid solutions, and analyzes their temperature-dependent properties and ZT performance.

Findings

Seebeck coefficients increase with temperature for all compounds.

Yb3Co4Sn13 exhibits a maximum ZT of 0.017 at 380 K.

Substituting Yb for Ce or La shifts the Seebeck coefficient to positive values.

Abstract

Crystallographic data and thermoelectric properties (from 240 K up to 380 K) of Yb3Co4Ge13, Yb3Co4Sn13 compounds and Yb2CeCo4Ge13 and Yb2.3La0.7Co4Ge13 solid solutions are reported. The Seebeck coefficients, electric resistance and thermal conductivity increase monotonically with increasing temperature from 240 to 380 K for all the compounds. The Seebeck coefficient is S = 14 - 27 \mu V//K for Yb3Co4Sn13, and S = -21 -- -12 \mu V/K for Yb3Co4Ge13. The substitution of Yb for cerium or lanthanum in Yb3Co4Ge13 shifts the Seeebeck coefficient to positive values. The Yb3Co4Sn13 has a maximal ZT parameter from available Pr3Rh4Sn13-type compounds. The ZT parameter of Yb3Co4Sn13 compound increases from 0.006 up to 0.017 with increasing temperature from 240 K to 380 K.