Huaihong Guo, Teng Yang, Peng Tao, Zhidong Zhang
We systematically study the potential of layered MoS$_2$ as a promising thermoelectric material for the first time, based on Boltzmann transport theory and first-principles calculations. Anisotropic thermoelectric transport property are investigated and compared with experimental data. A good agreement between our calculated temperature-dependent thermopower and available experimental data is obtained. We then discuss the temperature and doping level dependent thermopower, electrical conductivity, power factor (PF) and ultimately figure of merit (ZT) coefficient along in-plane and cross-plane directions. MoS$_2$ has a vanishingly small anisotropy of thermopower but a big anisotropy of electrical and thermal transport properties in the optimal doping region. A clear preference for thermoelectric transport under electron doping, as well as for the cross-plane transport direction is found. Our study demonstrates that it is essential to improve the thermoelectric performance of MoS$_2$ by reducing thermal conductivity through restacking exfoliated layers, or by electron doping through substituting at S site.
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http://arxiv.org/abs/1212.3394
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