Thermoelectric Characteristics of Solid-Solid Phase Transition Material VO2

Abstract

One of the problems of thermoelectric power generator is the fluctuation of output due to a temperature fluctuation of the heat source. To solve this problem, we propose a thermoelectric generator that uses vanadium dioxide (VO2), which is a latent heat storage material, as a thermoelectric material. VO2 is a solid-solid phase transition material and has a large latent heat associated with the phase transition. Therefore, the thermoelectric generator using VO2 may reduce the temperature fluctuation of the heat source and realize constant output. In this study, a VO2 sintered body was prepared and the thermoelectric properties of the VO2 sintered body was measured. The power factor, which is a measure of power generation performance of thermoelectric materials, of the VO2 sintered body increased significantly after the phase transition into the metallic phase, and reached 6 μWm^-1K^-2 at maximum.