Achieving high power factor and output power density in p-type half-Heuslers Nb _1-x Ti _x FeSb

TLDR

Thermoelectric technology can boost energy consumption efficiency by converting waste heat into electricity, and while reducing thermal conductivity has been widely pursued, increasing the power factor has seen less success. The study reports a successful power factor enhancement by improving carrier mobility. The authors achieved this by improving carrier mobility. The approach yielded a record power factor of ~106 μW·cm⁻¹·K⁻² at room temperature and a record output power density in a single‑leg device from 293 K to 868 K, demonstrating the importance of high power factor for power generation.

Abstract

Significance Thermoelectric technology can boost energy consumption efficiency by converting some of the waste heat into useful electricity. Heat-to-power conversion efficiency optimization is mainly achieved by decreasing the thermal conductivity in many materials. In comparison, there has been much less success in increasing the power factor. We report successful power factor enhancement by improving the carrier mobility. Our successful approach could suggest methods to improve the power factor in other materials. Using our approach, the highest power factor reaches ∼106 μW⋅cm −1 ⋅K −2 at room temperature. Such a high power factor further yields a record output power density in a single-leg device tested between 293 K and 868 K, thus demonstrating the importance of high power factor for power generation applications.