Recent progress in Bi-Te-based thermoelectric materials

Thermoelectric (TE) technology is becoming increasingly important in applications of solid-state cooling and renewable energy sources. Bi₂Te₃-based TE materials are widely used in small-scale cooling and temperature control applications; however, higher levels of TE performance are required for new applications such as large-scale cooling (e.g., domestic refrigerators or air conditioners) and for highly efficient power generation system. Recently, the TE performance of Bi₂Te₃-based materials has been remarkably enhanced by the introduction of nanostructuring technologies which can be used to prepare TE raw materials. Because it takes into account the theoretical and experimental characteristics, nanostructuring has been shown to be one of the most promising ways to realize the simultaneous control of the electronic and thermal transport properties. In this review, emphasis is placed on bulk-type nanostructured Bi₂Te₃-based TE materials. Nanostructuring technologies for enhanced TE performance are summarized, and a few important strategies are presented.