Thermal Rectification in Bulk Material Through Unusual Behavior of Electron Thermal Conductivity of Al-Cu-Fe Icosahedral Quasicrystal

Abstract

In this study, a new thermal rectifier working at high temperatures above 300 K was developed using Al61.5Cu26.5Fe12 icosahedral quasicrystal and Ag2Te. The thermal conductivity of Al61.5Cu26.5Fe12 increased drastically with temperature and, at 1000 K, reached a value nine times larger than that at 300 K. The thermal conductivity of Ag2Te showed a sudden decrease at around 400 K, and the thermal conductivity at 423 K became 60% smaller than that at 300 K. By making a composite consisting of Al61.5Cu26.5Fe12 icosahedral quasicrystal and Ag2Te, we succeeded in obtaining a large thermal rectification ratio (TRR) of |Jlarge|/|Jsmall| = 1.63 using two heat reservoirs maintained at TH = 543 K and TL = 300 K. The obtained TRR value is the largest among those ever reported for bulk thermal rectifiers.