Presenter: Prof. Hajime Nakanotani (Kyushu University University)
Topic: Manipulation of spin–multiplicity toward to development of ultra–high efficient organic light–emitting devices
Time: 9:00 AM, Mar. 26th ( Tuesday)
Location: 909-B
Abstract:
Since organic light-emitting diodes (OLEDs) possess extremely attractive properties such as highly efficient electroluminescence (EL), flexibility, lightweight, and the possibility of solution processing and low-cost manufacture, they are fascinating for advanced flexible displays and lighting applications. Since the recombination of four holes and electrons will yield one singlet exciton and three triplet excitons due to the rules of spin statistics in organic semiconductors 1, exciton production efficiency (hEP)—the fraction of electron–hole pairs converted into excitons that can emit light—in organic semiconductors under electrical excitation is a crucial parameter for realizing high-performance OLEDs with nearly 100% hEP 2-6.In this talk, our recent study on the manipulation of spin–multiplicityin molecular systems such as thermally-activated delayed fluorescence (TADF) and singlet fission sensitizing EL toward to the realization of over 100% hEP will be discussed.
References
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5. S. Hirata, Y. Sakai, K. Masui, H. Tanaka, S.Y. Lee, H. Nomura, N. Nakamura, M. Yasumatsu, H. Nakanotani, Q. Zhang, K. Shizu, H. Miyazaki, C. Adachi, Nat. Mater.14, 330-336 (2015).
6.H. Nakanotani, T. Higuchi, T. Furukawa, K. Masui, K. Morimoto, M. Numata, H. Tanaka, Y. Sagara, T. Yasuda. C. Adachi, Nat. Commun.5, 4016-4023 (2014).
Biography:
Research Interests:
Development of high efficiency and high performance organic light–emitting devices.
Understanding and controlling of the functions of molecular exciton.
Organic single crystal based opt–electronic devices.
Selected Representative Publications:
H. Noda, H. Nakanotani*, and C. Adachi,Excited state engineering for efficient reverse intersystem crossing” Science Advances, 2018, 4, eaao6910.
R. Nagata, H. Nakanotani*, and C. Adachi, “Exploiting singlet fission in organic light-emitting diodes” Advanced Materials, 2018, 30, 1801484.
C.-Y. Chan, M. Tanaka, H. Nakanotani, and C. Adachi, “Efficient and Stable Sky-Blue Delayed Fluorescence Organic Light-Emitting Diodes with CIEy < 0.4” Nature Communication, DOI:10.1038/s41467-018-07482-6.
T. Hosokai*, H. Matsuzaki, H. Nakanotani*, K. Tokumaru, T. Tsutsui, A. Furube, K. Nasu, H. Nomura, M. Yahiro and C. Adachi, “Evidence and mechanism of efficient thermally activated delayed fluorescence promoted by delocalized excited states”, Science Advances, 2017, 3, e1603282.
R. Nagata, H. Nakanotani* and C. Adachi*, “Near-Infrared Electrophosphorescence up to 1.1 µm using a Thermally Activated Delayed Fluorescence Molecule as Triplet Sensitizer”, Advanced Materials, 2016, 29, 1604265.
H. Nakanotani*, T. Furukawa, K. Morimoto and C. Adachi*, “Long-range coupling of electron–hole pairs in spatially separated organic donor–acceptor layers”, Science Advances, 2016, 2, e1501470.
H. Nakanotani, T. Higuchi, T. Furukawa, K. Masui, K. Morimoto, M. Numata, H. Tanaka, Y. Sagara, T. Yasuda, and C. Adachi*, “High efficiency organic light-emitting diodes with fluorescent emitters”, Nature Communication, 2014, 5, 4016.
Editor:Ming Lu