| 초록 |
SnTe is a lead-free thermoelectric material of which maximum power conversion efficiency is achievable in the intermediate temperature range of 600-900K. It is a promising less toxic alternative to PbTe. Compared to PbTe, SnTe has gotten less attention for thermoelectric applications because of its high thermal conductivity due to the high carrier concentration arising from inherent Sn vacancies in the lattice, very small band gap and a light-heavy hole valance bands large energy split. As a result, its thermoelectric figure of merit (ZT) has been limited to ~0.5 at 873K. In this work, we demonstrate thermal conductivity of SnTe could be suppressed down to ~1.2W/mK at 873K by incorporating fluidic Cu atoms into the interstitial voids of the SnTe lattices. As a result, the best composition sample exhibits a ZT ~1.5 at 873K. |
