RIKEN Center for Emergent Matter Science Emergent Functional Polymers Research Team
Team Leader: Keisuke Tajima (Ph.D.)
Research Summary

We work on the development of new organic semiconducting polymer materials and their application to organic electronic devices. Specifically, we seek the methodology and the molecular design to control the precise structures in molecular- and nano-scale at our will, and try to find breakthroughs to drastically enhance the performance of the organic electronic devices. Targets of our research are not only the conventional organic solar cells and field-effect transistors, but also the organic electronic devices with new functions based on the structure controls.
Main Research Fields
- Chemistry
Related Research Fields
- Engineering
Keywords
- Organic solar cells
- Semiconducting organic polymers
- Thin films
- Nanostructures
- Interfacial science
Selected Publications
- 1.
Wang, W.-C., Chen, S.-Y., Yang, Y.-W., Hsu, C. S., and Tajima, K.:
"Face-on Reorientation of π-Conjugated Polymers in Thin Films by Surface-Segregated Monolayers"
J. Mater. Chem. A 4, 2070013 (2020). - 2.
Nakano, K., Chen, Y., and Tajima, K.:
"Quantifying Charge Carrier Density in Organic Solar Cells by Differential Charging Techniques"
AIP Adv. 9, 125205 (2019). - 3.
Tajima, K.:
"Look Beyond the Surface: Recent Progress in Applications of Surface-segregated Monolayers for Organic Electronics"
Polym. J. 51, 1117 (2019). - 4.
Nakano, K., Chen, Y., Xiao, B., Han, W., Huang, J., Yoshida, H., Zhou, E. J., and Tajima, K.:
"Anatomy of the Energetic Driving Force for Charge Generation in Organic Solar Cells"
Nat. Comm. 10, 2520 (2019). - 5.
Wang, F., Nakano, K., Segawa, H., and Tajima, K.:
"Phytol-derived Alkyl Side-chains for ¬π-Conjugated Semiconducting Polymers"
Chem. Mater. 31, 2097 (2019). - 6.
Wang, F., Nakano, K., Yoshida, H., Hashimoto, K., Segawa, H., Hsu, C.-S., and Tajima, K.:
"Effects of End-On Oriented Polymer Chains at the Donor/Acceptor Interface in Organic Solar Cells"
J. Mater. Chem. A 6, 22880 (2018) - 7.
Wang, F., Hashimoto, K., Segawa, H., and Tajima, K.:
"Synthesis of Poly(3-butylthiophene) with Trisiloxane End Group and Its Surface Segregation Behavior inThin Films"
J. Photopolym. Sci. Tech. 31, 151 (2018) - 8.
Wang, C., Nakano, K., Lee, H. F., Chen, Y., Hong, Y.-L., Nishiyama, Y., and Tajima, K.:
"Intermolecular Arrangement of Fullerene Acceptors around Semiconducting Polymers in Mixed Bulk Heterojunctions"
Angew. Chem. Int. Ed 57, 7034 (2018) - 9.
Wang, F., Hashimoto, K., Segawa, H., and Tajima, K.:
"Effects of Chain Orientation in Self-Organized Buffer Layers Based on Poly(3-alkylthiophene)s for Organic Photovoltaics"
ACS Appl. Mater. Interfaces 10, 8901 (2018) - 10.
Ohnishi, I., Hashimoto, K., and Tajima K.:
"Synthesis of Diketopyrrolopyrrole-based Polymers with Polydimethylsiloxane Side Chains And Their Application in Organic Field-effect Transistors"
R. Soc. open sci. 5, 172025 (2018)
Recent Research Results
Feb. 1, 2024
Organic semiconductors with proton-hopping promiseSep. 27, 2018
A self-powered heart monitor taped to the skinNov. 6, 2015
Light-absorbing polymers stand to attentionJun. 12, 2015
Working at the interface for future energy
Related Links
Lab Members
Principal investigator
- Keisuke Tajima
- Team Leader
Core members
- Kyohei Nakano
- Research Scientist
- Hitoshi Saito
- Special Postdoctoral Researcher
- Takaho Yokoyama
- Postdoctoral Researcher
- Hyeonwoo Jung
- Postdoctoral Researcher
- Yumiko Kaji
- Technical Staff II
- Akira Ohno
- Visiting Scientist
Contact Information
N301-1, Chemistry and Materials Physics Building,
2-1 Hirosawa, Wako,
Saitama 351-0198, Japan
Email: keisuke.tajima [at] riken.jp