REQUIREMENTS AND PROSPECTS FOR COMPETITIVE THERMOELECTRIC MATERIALS

摘要

Practical thermoelectric devices have conversion efficiencies of 5-10%, corresponding to material figures-of-merit (FOMs) of ZT ≈ 1.These efficiencies are much inferior to those of commercial electricity generators or vapor-compression refrigerators. In this paper, thermoelectric efficiency is examined from the standpoint of the FOMs that would enable thermoelectrics to compete successfully with conventional machines. It is argued that ZT≥8 will be required. Some emerging new bulk materials may eventually reach that performance level, but probably not in the near term if historical trends apply. Multilayer thin films appear to have the best chance of attaining the requisite FOMs within the next few years.