Anisotropic Thermoelectric Generator Made from Single Crystal Bi Microwire

Abstract

Currently, for thermoelectric conversion of heat most widely used is the approach based on the Seebeck and Peltier effects created at the interface of two materials with different values S of the Seebeck coefficient. Another type of thermoelectric converter is the anisotropic thermoelement (AT) using anisotropy of thermoelectric power. AT has some advantages: - the transverse thermopower, unlike a conventional thermocouple, is proportional to the temperature gradient (T1- T2)/h instead of the temperature difference T1-T2; - Voltage V is proportional to the length l of AT. To increase the AT output voltage we need either increase the length l of AT or decrease its thickness h. According to our experimental data, to obtain a thermoelectric voltage of 1 V at a transverse temperature gradient of 5 K, the microwire with a diameter of 2 μm and a length of 8 m must be used. In our experimental sample the long wire in glass coating was wound into a flat spiral.