A potential thermoelectric material CuAlO2 is theoretically studied. We first construct a model Hamiltonian of CuAlO2 based on the first principles band calculation, and calculate the Seebeck coefficient. Then, we compare the model with that of a well-known thermoelectric material NaxCoO2, and discuss the similarities and the differences. It is found that the two materials are similar from an electronic structure viewpoint in that they have a peculiar pudding-mold type band shape, which is advantageous as thermoelectric materials. There are however some differences, and we analyze the origin of the difference from a microscopic viewpoint. The band shape of CuAlO2 is found to be even more ideal than that of NaxCoO2, and we predict that once a significant amount of holes is doped in CuAlO2, thermoelectric properties (especially the power factor) even better than that of NaxCoO2 can be expected.
@article{arxiv.1304.2526,
title = {Pudding-mold type band in a potential thermoelectric material CuAlO$_2$ : comparison with Na$_x$CoO$_2$},
author = {Kouta Mori and Hirofumi Sakakibara and Hidetomo Usui and Kazuhiko Kuroki},
journal= {arXiv preprint arXiv:1304.2526},
year = {2013}
}