2021 Fiscal Year Final Research Report

Spectral control of near-field thermal radiation for highly efficient thermo-photovoltaic power generation

Research Project

PDF

Project/Area Number	17H06125
Research Category	Grant-in-Aid for Scientific Research (S)
Allocation Type	Single-year Grants
Research Field	Optical engineering, Photon science
Research Institution	Kyoto University
Principal Investigator	NODA Susumu 京都大学, 工学研究科, 教授 (10208358)
Co-Investigator(Kenkyū-buntansha)	浅野卓京都大学, 工学研究科, 准教授 (30332729) 井上卓也京都大学, 工学研究科, 助教 (70793800)
Project Period (FY)	2017-05-31 – 2022-03-31
Keywords	熱輻射制御 / 近接場 / フォトニック結晶 / 熱光発電 / 太陽電池 / 半導体
Outline of Final Research Achievements	In this research, we aimed to establish a method of extracting thermal radiation that exceeds the conventional power limit (blackbody limit) by using a system in which a high-temperature emitter and a photovoltaic cell are brought into close proximity via an intermediate substrate, and to establish the foundation for the development of high-power, high-efficiency thermophotovoltaic power generation systems. As a result, we have developed a systematic theory of near-field thermal radiation control and fabricated a near-field thermophotovoltaic device that integrated a high-temperature (up to 1200 K) thermal emitter and a room-temperature photovoltaic cell with a sub-wavelength gap (<140 nm). By using the developed device, we have succeeded for the first time in extracting near-field thermal radiation and photocurrent exceeding the blackbody limit in a single device.
Free Research Field	光工学および光量子科学
Academic Significance and Societal Importance of the Research Achievements	近接場熱輻射制御に関する体系的な理論構築とともに、高温の熱輻射光源と室温の受光素子を、中間基板を介して距離140nm以下に近接させた一体型熱光発電デバイスの開発を通じて、黒体限界を超える熱輻射および光電流を得ることに成功した本成果は、世界的にも例が無く、学術的に極めて意義のある成果であると言える。さらに、黒体限界を超える光電流を取り出すことに成功したことは、現在の太陽光発電の効率を凌駕する超小型かつ高効率な次世代発電システムの実現にもつながる重要な成果と言え、太陽熱・地熱等の各種熱エネルギーの有効利用を可能とし、将来の脱炭素社会の実現に貢献出来ることが期待され、その社会的意義も大きいと言える。