[21p-438-1~12] 9.4 Thermoelectric conversion

△ [21p-438-6] Effects of defects induced by pressure on thermoelectric material CuGaTe₂

〇(D)Yosuke Fujii¹, Hiroki Funashima², Hiroshi Yoshida³, Ikuya Yamada¹, Atsuko Kosuga^1,4 (1.Osaka Pref. Univ., 2.Kobe Univ., 3.Tokyo Univ., 4.JST, PRESTO.)

Keywords:thermoelectric material, defect

We analyzed the effects of defects on thermoelectric CuGaTe₂ chalcopyrite structure materials prepared by room-temperature high-pressure treatment. We will introduce defects induced by high-pressure treatment at room-temperature. Cation-disorder at Cu and Ga sites in CuGaTe₂ were found to arise with pressure, which was determined by crystal structure analysis. We predict, from the calculated formation energy, that such disorder can be induced as a metastable structure The effects of defects on their thermal conductivity, electrical properties, and band structure will be also discussed.