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Phase separation and nanostructuring in the thermoelectric material PbTe1-xSx

H. Lin·E. S. Bozin·S. J. L. Billinge·J. Androulakis·C. H. Lin·M. G. Kanatzidis
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Abstract

The average and local structures of the (PbTe)1-x(PbS)x system of thermoelectric materials has been studied using the Rietveld and atomic pair distribution function (PDF) methods. Samples with 0:25 < x are macroscopically phase separated. Phase separation was suppressed in a quenched x = 0:5 sample which, nonetheless, exhibited a partial spinodal decomposition. The promising thermoelectric material with x = 0:16 showed intermediate behavior. Combining TEM and bulk scattering data suggests that the sample is a mixture of PbTe rich material and a partially spinodally decomposed phase similar to the quenched 50% sample. This results in a nano-meter scale inhomogeneous material that accounts for its very low thermal conductivity.

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H. Lin, E. S. Bozin, S. J. L. Billinge, J. Androulakis, C. H. Lin, M. G. Kanatzidis. 2006-12-15. Phase separation and nanostructuring in the thermoelectric material PbTe1-xSx. https://arxiv.org/abs/cond-mat/0612414

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