The thermoelectric properties of single-crystalline and polycrystalline n-type Ba8CuxSi46−x type I clathrate were investigated and compared. Single-crystalline Ba8CuxSi46−x clathrate was synthesized by the Czochralski (CZ) method with a Cu content gradient, while spark plasma sintering (SPS) was used for the reorganization of polycrystalline materials. The same Cu content resulted in almost the same Seebeck coefficient in both single-crystalline and polycrystalline crystals, while the power factor (PF = S2/ ρ) of single-crystalline clathrate is twice that of polycrystalline clathrate. Thus, single crystallization is effective for the synthesis of high-efficiency thermoelectric materials in a type I Ba8CuxSi46−x clathrate ternary system.
All Science Journal Classification (ASJC) codes