Propertiy-based Novel Materials Design of Layered Thermoelectric Oxides with Bulk Nano-Interfaces

2014 Fiscal Year Final Research Report

• Project/Area Number: 24560825
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Inorganic materials/Physical properties
• Research Institution: Osaka University
• Principal Investigator: YOSHIYA Masato 大阪大学, 工学(系)研究科(研究院), 准教授 (00399601)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 熱電変換 / 層状構造 / 熱伝導 / 第一原理計算 / 分子動力学法 / 電子伝導 / 酸化物熱電材料

Outline of Final Research Achievements

Origins of electronic and thermal properties that thermoelectric energy conversion efficiency have been revealed by computational experiments, in addition to mechanism behind stabilization of the layered structure. It has been revealed that, in NaxCoO2 and related materials, interlayer distance significantly affects both electronic and thermal properties and thermodynamic stability, and, in Ca3Co4O9 and its sister materials, dynamic interference of atomic vibrations across interfaces suppresses thermal conduction in CoO2 layer which carries most of heat in the material. In addition, each layer in TinO2n-1 and its sister materials plays different role with TiO2 layers dominating heat transport while Ti2O3 layers govern electronic properties. Based on those in-depth understandings, new strategies to control electronic and thermal properties by fully utilizing their layered structure, thereby improving thermoelectric conversion, have been obtained.

Free Research Field

計算材料物理学