Controling Interfacial Structure in Mixed Films for Efficient Organic Solar Cells

• Project/Area Number: 16H07421
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Device related chemistry
• Research Institution: Institute for Molecular Science
• Principal Investigator: Izawa Seiichiro 分子科学研究所, 物質分子科学研究領域, 助教 (60779809)
• Project Period (FY): 2016-08-26 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
• Keywords: 有機太陽電池 / 有機半導体 / 界面 / 電荷再結合 / 電荷分離 / ドーピング / エネルギー準位接続 / 有機薄膜太陽電池 / 界面構造 / ドナー／アクセプター界面

Outline of Final Research Achievements

Organic solar cells attract much attention as future energy conversion devices due to their advantages such as low manufacturing cost and flexibility. In this study, we controlled the structure of the electron donor/acceptor interfaces where charge separation and recombination occurred in the mixed film. We clarified the relationship between the nanostructure and the photoelectric conversion process, and improved the performance. First, we controlled the mixed state near the interface by the difference of polymer side chain structure, and clarified the necessity of weakening Coulomb binding energy in order to improve the open-circuit voltage. We also succeeded in controlling the open-circuit voltage by impurity doping.

Research Products

• [Journal Article] Effect of trap-assisted recombination on open-circuit voltage loss in phthalocyanine/fullerene solar cells (2018)
  • Author(s): Shintaku Naoto、Hiramoto Masahiro、Izawa Seiichiro
  • Journal Title: Organic Electronics Volume: 55 Pages: 69-74
  • DOI: 10.1016/j.orgel.2018.01.016
  • Peer Reviewed
• [Journal Article] Crystallization and Polymorphism of Organic Semiconductor in Thin Film Induced by Surface Segregated Monolayers (2018)
  • Author(s): Izawa Seiichiro、Nakano Kyohei、Suzuki Kaori、Chen Yujiao、Kikitsu Tomoka、Hashizume Daisuke、Koganezawa Tomoyuki、Nguyen Thuc-Quyen、Tajima Keisuke
  • Journal Title: Scientific Reports Volume: 8 Issue: 1 Pages: 481-491
  • DOI: 10.1038/s41598-017-18881-y
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Doping for Controlling Open-Circuit Voltage in Organic Solar Cells (2018)
  • Author(s): Shintaku Naoto、Hiramoto Masahiro、Izawa Seiichiro
  • Journal Title: Journal of Physical Chemistry C Volume: 122 Issue: 10 Pages: 5248-5253
  • DOI: 10.1021/acs.jpcc.7b12203
  • Peer Reviewed
• [Journal Article] Hall Effect in Bulk-Doped Organic Single Crystals (2017)
  • Author(s): C. Ohashi, S. Izawa, Y. Shinmura, M. Kikuchi, S. Watase, M. Izaki, H. Naito, and M. Hiramoto
  • Journal Title: Adv. Mater. Volume: 29 Issue: 23 Pages: 1605619-1605619
  • DOI: 10.1002/adma.201605619
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Hole- and electron-only transport in ratio-controlled organic co-deposited films observed by impedance spectroscopy (2017)
  • Author(s): Shintaku Naoto、Izawa Seiichiro、Takagi Kenichiro、Naito Hiroyoshi、Hiramoto Masahiro
  • Journal Title: Organic Electronics Volume: 50 Pages: 515-520
  • DOI: 10.1016/j.orgel.2017.08.020
  • Peer Reviewed
• [Journal Article] Drawing organic photovoltaics using paint marker pens (2017)
  • Author(s): Suzuki Kaori、Izawa Seiichiro、Chen Yujiao、Nakano Kyohei、Tajima Keisuke
  • Journal Title: AIP Advances Volume: 7 Issue: 11 Pages: 115002-115008
  • DOI: 10.1063/1.5006352
  • Peer Reviewed / Open Access
• [Presentation] 膜中のバンドの曲がりが有機太陽電池の開放端電圧に与える影響 (2018)
  • Author(s): 伊澤 誠一郎、新宅 直人、平本 昌宏
  • Organizer: 応用物理学会 春季学術講演会
• [Presentation] ドナー/アクセプター界面の結晶性が有機薄膜太陽電池の開放電圧に与える影響 (2017)
  • Author(s): 伊澤 誠一郎、菊地 満、新宅 直人、平本 昌宏
  • Organizer: 応用物理学会 秋季学術講演会
• [Presentation] Induced Crystallization of [6,6]-Phenyl-C61-Butyric Acid Methyl Ester in Thin Films by Surface Segregated Monolayers (2017)
  • Author(s): Seiichiro Izawa, Kyohei Nakano, Kaori Suzuki,Yujiao Chen, Tomoka Kikitsu, Daisuke Hashizume, Tomoyuki Koganezawa, Thuc-Quyen Nguyen, Keisuke Tajima
  • Organizer: European Conference, Molecular Electronics 2017
• [Presentation] Induced Crystallization of Organic Semiconductorin Thin Films by Surface Segregated Monolayers (2017)
  • Author(s): Seiichiro Izawa, Kyohei Nakano, Kaori Suzuki,Yujiao Chen, Tomoka Kikitsu, Daisuke Hashizume, Tomoyuki Koganezawa, Thuc-Quyen Nguyen, Keisuke Tajima
  • Organizer: 27th International Photovoltaic Science and Engineering Conference
  • Int'l Joint Research
• [Presentation] 有機薄膜太陽電池で電荷再結合を抑制するためのドナー/アクセプター界面構造 (2017)
  • Author(s): 伊澤 誠一郎、菊地 満、新宅 直人、平本 昌宏
  • Organizer: 応用物理学会 春季学術講演会
  • Place of Presentation: パシフィコ横浜、横浜市、神奈川県
• [Presentation] 有機電子デバイスの高性能化に向けた界面構造制御 (2017)
  • Author(s): 伊澤誠一郎
  • Organizer: SPring-8 次世代先端デバイス研究会
  • Place of Presentation: ＡＰ品川、港区、東京都
  • Invited
• [Presentation] Effects of Energetics at Donor/Acceptor Interfaces on Organic Solar Cells (2016)
  • Author(s): Seiichiro Izawa, Kyohei Nakano, Kaori Suzuki, Keisuke Tajima
  • Organizer: KJF International Conference on Organic Materials for Electronics and Photonics 2016
  • Place of Presentation: ACROS Fukuoka, Fukuoka
  • Int'l Joint Research