Experimental relationship between the Seebeck and Peltier effects in thermoelectric modules based on Fe and Al metals

Abstract

Thermoelectric modules (TEMs) based on resource-rich metals with a high thermoelectric performance are expected to be environmentally friendly technologies for electric power and heat generation. The relationship between the Seebeck and Peltier effects in Fe−Al TEMs was investigated to clarify the thermoelectric mechanism of metal-based TEMs. The TEMs with various Seebeck coefficients ranging from 1.8 to 12.7 μV/K were fabricated. The Peltier effect was analyzed based on a model established using the current direction and temperature difference. During the application of current from Fe to Al and from Al to Fe, heat absorption and generation were observed at the Fe−Al interface, respectively. The quasi-Peltier coefficients of the TEMs, calculated from the proposed model, were highly proportional to the Seebeck coefficient. These results suggest that the number of interfacial charges between the Fe and Al metals determines the thermoelectric performance. The tailoring of these charges could be an avenue to improve the thermoelectric performance in the design of high-performance metal-based TEMs.