Exclusive occurrence of photoinduced energy transfer and switching of its direction by rectangular pi-extension of nanographenes
- 주제(기타) Chemistry, Multidisciplinary
- 설명문(일반) [Umeyama, Tomokazu; Hanaoka, Takuma; Yamada, Hiroki; Namura, Yuki; Mizuno, Satoshi; Ohara, Tomoya; Baek, Jinseok; Park, JaeHong; Imahori, Hiroshi] Kyoto Univ, Dept Mol Engn, Grad Sch Engn, Nishikyo Ku, Kyoto 6158510, Japan; [Takano, Yuta; Imahori, Hiroshi] Kyoto Univ, Inst Integrated Cell Mat Sci WPI ICeMS, Sakyo Ku, Kyoto 6068501, Japan; [Stranius, Kati; Tkachenko, Nikolai V.] Tampere Univ, Fac Engn & Nat Sci, Korkeakoulunkatu 8, Tampere 33720, Finland
- 등재 SCIE, SCOPUS
- 발행기관 ROYAL SOC CHEMISTRY
- 발행년도 2019
- 총서유형 Journal
- URI http://www.dcollection.net/handler/ewha/000000172004
- 본문언어 영어
- Published As https://dx.doi.org/10.1039/c9sc01538h
초록/요약
As structure defined cutouts of the graphene lattice, nanographene molecules have gained plenty of attention because of their high potential for versatile applications in organic electronics and energy conversion devices and as ideal model systems for the better understanding of intrinsic structure-property correlations of graphenes. In this study, well-defined nanographenes with sp(2) carbon networks of different sizes, hexa-peri-hexabenzocoronene (HBC) and its rectangularly pi-extended version, a short graphene nanoribbon (GNR), have been covalently functionalized with photoactive porphyrin molecules. On the basis of their spectroscopic studies, the photodynamics of the porphyrin-linked nanographenes was found to be influenced substantially by the size of the nanographenes. Photoexcitation of the porphyrin-HBC linked system led to exclusive energy transfer (EnT) from the first singlet excited state (S-1) of the nanographene to the porphyrin, whereas opposite selective EnT occurred from the first and second singlet excited states (S-1 and S-2) of the porphyrin to the nanographene in the porphyrin-GNR linked system. In particular, ultrafast efficient EnTs from both the S-2 and S-1 states of the porphyrin to GNR mimic the corresponding ultrafast EnTs from the S-2 and S-1 states of carotenoids to chlorophylls in light-harvesting systems of natural photosynthesis. Such unique photophysical properties will be useful for the rational design of carbon-based photofunctional nanomaterials for optoelectronics and solar energy conversion devices.
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