Search for high-mobility thermoelectric material with super-ionic conductivity and control of lattice disorder

2014 Fiscal Year Final Research Report

• Project/Area Number: 25620040
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Inorganic chemistry
• Research Institution: The University of Tokyo
• Principal Investigator: ISHIWATA Shintaro 東京大学, 工学(系)研究科(研究院), 准教授 (00525355)
• Co-Investigator(Renkei-kenkyūsha): SAKAI Hiswaki 東京大学, 大学院工学系研究科, 助教 (20534598)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 熱電変換 / 層状遷移金属カルコゲナイド / ゼーベック効果 / 超イオン伝導

Outline of Final Research Achievements

To search for a high-performance thermoelectric material showing low thermal conductivity as low as a glass in addition to high electronic conductivity, we studied the effect of controlling domain on thermoelectric properties and synthesized new compounds of layered transition-metal chalcogenides. First, we found that a polycrystalline sample of CuAgSe with superionic conductivity shows an enhanced power factor at low temperatures below 200 K by enlarging the size of domains. Second, we examined Nb-doping effect on 1T-MoTe2, which is known as a high-mobility semimetal, and found that the 10%-doped sample shows an improved figure of merit (ZT~0.02) at room temperature and that the 60%-doped sample crystallizes in new 3R polytype without inversion symmetry.

Free Research Field

固体化学、物性物理