Network theory for inhomogeneous thermoelectrics
Abstract
The Onsager-de Groot-Callen transport theory, implemented as a network model, is used to simulate the transient Harman method, which is widely used experimentally to determine all thermoelectric transport coefficients in a single measurement setup. It is shown that this method systematically overestimates the Seebeck coefficient for samples composed of two different materials. As a consequence, the figure of merit is also overestimated, if the thermal coupling of the measurement setup to the environment is weak. For a mixture of metal and semiconductor particles near metal percolation the figure of merit obtained by the Harman method is more than 100 \% too large. For a correct interpretation of the experimental data, information on composition and microstructure of the sample are indispensable.
Cite
@article{arxiv.1512.04235,
title = {Network theory for inhomogeneous thermoelectrics},
author = {Sebastian Angst and Dietrich E. Wolf},
journal= {arXiv preprint arXiv:1512.04235},
year = {2016}
}