| 초록 |
Thermoelectric technology allows direct and reversible conversion between heat and electricity. SnSe is a representative thermoelectric material with the high thermoelectric performance in the temperature range of 773− 923 K. The high thermoelectric performance of SnSe mainly originates from its highly anisotropic crystal structure and favorable electronic and phonon band structures. Due to its intrinsic p-type nature, most researches have focused on p-type SnSe and thus the stabilization of n-type carrier at the optimal level is still challenging. In this presentation, we report high performance n-type polycrystalline SnSe system by halogen doping. We optimize electron carrier concentration of n-type SnSe system by controlling doping level, which improves power factors significantly. Simultaneously, thermal conductivities are reduced due to point defect scattering of heat-carrying phonon. As a result, the optimized samples show a high thermoelectric figure of merit of ~1.25 at 800 K. |
