| 초록 |
Simple binary compound SnSe has attracted widespread attention due to high thermoelectric figure of merit ZT in its single crystal form. For thermoelectric devices that consist of numerous couples of n- and p-type thermoelectric legs, it is required to develop both types of materials with high performance. However, their n-type SnSe based compounds are largely underdeveloped and exhibit poorer performance than that of p-type counterpart. Here we report new n-type polycrystalline SnSe systems that are dually introduced with Cl and PbSe. Cl doping induces the n-type conduction behavior in SnSe and PbSe alloying optimizes the carrier concentration, resulting in a peak ZT of ~1.2 at 823 K. Importantly, in spite of highly anisotropic layered structure of SnSe, we obtain comparable ZT along the perpendicular and parallel to the press direction of spark plasma sintering by developing different fabrication processes specialized for both the directions. |
