In‐Situ Loading Bridgman Growth of Mg3Bi1.49Sb0.5Te0.01 Bulk Crystals for Thermoelectric Applications

Abstract

Abstract The single crystal growth of Mg3Bi2‐based thermoelectric materials is of great significance for their applications near room temperature. So far, it is still a big challenge to grow such bulk single crystals and attempts are primarily focused on the metal flux methods. For the first time, bulk single crystals of n‐type Mg3Bi1.49Sb0.5Te0.01 are directly grown by applying an In‐situ Loading Bridgman method. The as‐grown single crystal features an excellent carrier mobility of 220 cm2 V−1 s−1, which is among the best compared to other Mg3Bi2‐based bulk materials. Besides, this method is successfully developed to fast grow uniform polycrystalline materials with high thermoelectric and mechanic performance. As demonstrated by the single‐leg device, a large temperature difference of 10.5 K is achieved at the supplied electric current of 0.6 A, much superior to other room temperature state‐of‐the‐art thermoelectric materials. With the single crystalline and polycrystalline materials prepared reliably and conveniently, in‐depth investigations on the Mg3Bi2 thermoelectric system can be greatly benefited, which should as well significantly facilitate their practical applications at room temperature.

Keywords

• Bridgman crystal growth
• bulk crystals
• Mg 3Bi 2‐based alloys
• single‐leg devices
• thermoelectric materials