[8a-Z18-1~11] 9.4 Thermoelectric conversion

[8a-Z18-7] Lowering the lattice thermal conductivity of colusite via interstitial doping

〇Koichiro Suekuni¹, Yuta Shimizu¹, Hikaru Saito¹, Raju Chetty², Michihiro Ohta², Toshiro Takabatake³, Michitaka Ohtaki¹ (1.Kyushu Univ., 2.AIST GZR, 3.Hiroshima Univ.)

Keywords:thermoelectric materials, sulfides, lattice thermal conductivity

Atomic-scale defects/disordered states are thought to be responsible for lowering the lattice thermal conductivity for thermoelectric colusites. In this study, we investigated the effect of interstitial Cu atoms (defects) on the thermal conductivity for Cu₂₆V₂Ge₆S₃₂ colusite. The thermal conductivity was compared between Cu-doped and non-doped samples with equivalent hole carrier concentration. The former sample showed suppressed thermal conductivity, indicating the strong phonon scattering due to the introduction of interstitial Cu atoms.