Study of thermoelectric material design with caged and randomly substituted structures by using quantum interference effects of electrons

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K06487
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Yamaguchi University
• Principal Investigator: Akai Koji 山口大学, 国際総合科学部, 准教授 (20314825)
• Co-Investigator(Kenkyū-buntansha): 岸本 堅剛 山口大学, 大学院創成科学研究科, 助教 (50234216)
• Research Collaborator: MATSUURA MITSURU 山口大学, 名誉教授
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 熱・エネルギー材料 / 熱電クラスレート半導体 / 電子状態

Outline of Final Research Achievements

In the present study, we calculated the electronic structure of clathrate semiconducting compounds, and then host group-IV atoms are randomly substituted for group-III atoms and the relation of the crystal structure with the mechanism of the high carrier mobility was discussed. The electronic structure calculation had been performed for type-I and type-VIII clathrate semiconductors Ba-Ga-Sn and the type-II clathrate semiconductor K-Ba-Ga-Sn, respectively. We found the interesting correlation between the carrier mobility and the interaction that is brought by the rattling guest atoms and electrons at the states of the lowest energy conduction band, and we studied the mostly localized Wannier functions to analyze the carrier scattering effects by the atomic substitution for host sites.

Free Research Field

工学