Methodology of thermoelectric performance enhancement by hybridization of electronic quantum states and high conductivity states

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K22110
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 28:Nano/micro science and related fields
• Research Institution: Osaka University
• Principal Investigator: Nakamura Yoshiaki 大阪大学, 基礎工学研究科, 教授 (60345105)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: 熱電材料 / 透明材料 / ナノワイヤ / ナノ構造物理 / 量子閉じ込め構造

Outline of Final Research Achievements

In this study, we are aiming at developing a methodology of thermoelectric performance enhancement using the proposed nanostructure, namely a film including epitaxial core-shell nanowires. Therein, the shell layers are quantum-confined low dimensional structures with sharp density of states having high Seebeck coefficient and nanowires have high electrical conductivity and low thermal conductivity. It is expected that the confined states penetrate into the nanowires, leading to the high Seebeck coefficient and high electrical conductivity. We succeeded in the formation of films including ZnO/Mg0.1Zn0.9O core-shell nanowires, which shows higher Seebeck coefficient than ZnO films without nanowires. Although the detail study is needed to elucidate the mechanism, this result gives the clue to new methodology of thermeolecrric performance enhancement by nanostructuring

Free Research Field

ナノ構造物理

Academic Significance and Societal Importance of the Research Achievements

この研究は、ナノ構造を用いて量子状態を操作することで熱電変換効率を増大させるという新しい性能向上の方法論を打ち出すものであり、高い学術的意義を有する。また、この手法は、ユビキタス元素からなる酸化物に適用できるため、将来、環境調和型の透明熱電材料実現への道を拓くという社会的インパクトを与えるものである。