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arXiv · 2205.08559

The Highly Disordered Zintl Phase Ca$_{10}$GdCdSb$_9$ -- New Example of a p-type Semiconductor with Remarkable Thermoelectric Properties

Michael O. Ogunbunmi·Svilen Bobev
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Abstract

Ca$_{10}$GdCdSb$_9$ is a new Zintl phase with a large unit cell volume (~2500 {\AA}3) and a very complex, disordered structure, which can drive the realization of ultralow thermal conductivity in this material. The measured Seebeck coefficient, $\alpha$, for single-crystalline Ca$_{10}$GdCdSb$_9$ approaches 350 $\mu$V/K at 600 K. The experimentally determined electrical resistivity of Ca$_{10}$GdCdSb$_9$ is very low, leading to a remarkably high-power factor PF of 23.2 $\mu$W/cm.K$^2$ at 460 K. The extraordinary PF value in this material, higher than those of the currently known state-of-the-art materials within the same temperature range, suggests that the Ca$_{10}$RECdSb$_9$ material system (RE = rare earth metal) could serve as a viable playground to harnessing new efficient thermoelectric generators.

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Michael O. Ogunbunmi, Svilen Bobev. 2022-05-17. The Highly Disordered Zintl Phase Ca$_{10}$GdCdSb$_9$ -- New Example of a p-type Semiconductor with Remarkable Thermoelectric Properties. https://arxiv.org/abs/2205.08559

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