FY2019 Annual Report

Organic and Carbon Nanomaterials Unit
Assistant Professor Akimitsu Narita


The unit aims to synthesize novel organic and carbon nanomaterials with atomically precise structures, and to elucidate their electronic, optical and other physical and chemical properties while exploring their applications. The unit has especially focused on the synthesis of large polycyclic aromatic hydrocarbons (PAHs), consisting of multiple fused benzene rings which can also be nanoscale graphene fragments. Such large PAHs are thus often called nanographenes or graphene quantum dots, and possess intriguing optical, electronic, and magnetic properties that are sensitively dependent on their chemical structures. Nanometer-wide strips of graphene, namely graphene nanoribbons (GNRs), can also be synthesized by the so-called bottom-up approach using similar techniques of organic and polymer chemistry, giving rise to next-generation quasi-one-dimensional nanocarbon materials that are complementary to carbon nanotubes. FY2019 was the second year of the unit after it launched in late 2018 upon the adjunct appointment of Prof. Akimitsu Narita. The unit welcomed its first postdoc, Dr. Xiushang Xu, and mainly worked in collaboration with Prof. Klaus Müllen's group at the Max Planck Institute for Polymer Research in Mainz, Germany. We have written an Account-type article about PAHs and GNRs as an invited contribution to the Bulletin of the Chemical Society of Japan. Prof. Narita also wrote two invited articles in Japanese for Kobunshi (高分子; Polymers) of the Society of Polymer Science, Japan, and Oyo Buturi (応用物理; Applied Physics) of the Japan Society of Applied Physics as well as co-authoring a progress report article for Advanced Materials. Preparation of the laboratory located in Lab 4 commenced after the completion of the latter's construction in late 2019, with the installation of necessary research equipment including glass vacuum manifolds, rotary evaporators, and analytical and preparative high performance liquid chromatography. Moreover, Prof. Narita has successfully acquired a JSPS KAKENHI grant (Returning Researcher Development Research; 19K24686).

1. Staff

  • Dr. Xiushang Xu, Postdoctoral Scholar

2. Collaborations

2.1 Synthesis and Characterizations of Large Polycyclic Aromatic Hydrocarbons and Atomically Precise Graphene Nanoribbons

  • Type of collaboration: Joint research
  • Researchers:
    • Professor Klaus Müllen, Max Planck Institute for Polymer Research, Mainz, Germany
    • Professor Roman Fasel, Empa, Swiss Federal Laboratories for Materials Science and Technology, Dübendorf, Switzerland
    • Professor Xinliang Feng, Technical University of Dresden, Germany

2.2 Investigations of Photoluminescence Properties of Carbon Nanomaterials 

  • Type of collaboration: Joint research
  • Researchers:
    • Professor Jean-Sébastien Lauret, Ecole Normale Supérieure de Paris Saclay, Orsay cedex, France
    • Dr. Stéphane Campidelli, CEA-Saclay, Gif sur Yvette, France

3. Activities and Findings

3.1 Synthesis and Characterizations of Large Polycyclic Aromatic Hydrocarbons as Atomically Precise Graphene Quantum Dots and Their Functionalization

Graphene quantum dots (GQDs) are attracting attention as heavy-metal free and environmentally friendly counterparts of semiconductor quantum dots, and especially investigated as light-emitting materials in Materials Science. However, GQDs reported in the literature typically have undefined and non-uniform chemical structures, resulting in mixtures of GQDs having varying properties, for example resulting in broad emission spectra. In contrast, organic synthesis allows for fabrication of atomically precise GQDs, or nanographenes, which are identical to large polycyclic aromatic hydrocarbons (PAHs). The properties of PAHs are highly dependent on their chemical structures, and thus it is highly relevant to achieve PAHs with novel structures. Prof. Narita, Prof. Müllen, and their colleagues have previously reported a synthesis of dibenzo[hi,st]ovalene (DBOV) as a novel PAH (nanographene/GQD) with a combination of zigzag and armchair edges, which demonstrated very strong red emission and stimulated emission, rendering it interesting for applications in light-emitting devices, not only in light-emitting diodes but also in lasers (cf. publication 2 in 4.1 below). Moreover, DBOV has been revealed to be capable of single-photon emission (publication 9 in 4.1), relevant for quantum information technology, as well as “blinking” that is essential for fluorophores used in the single-molecule localization microscopy (publication 6 in 4.1), which is a modern super-resolution microscopy technique. The organic synthesis also allows for introduction of various functional groups at the edges of GQDs, and installment of two 3,4,5-tris(dodecyloxy)phenyl groups on DBOV induced its self-assembly into helical columnar structures, demonstrating discotic liquid crystalline properties (publication 10 in 4.1). Furthermore, extension of the aromatic core structure of DBOV through regioselective bromination and transition-metal catalyzed annulation of acetylenes led to circumpyrene as an unprecedented PAH (publication 4 in 4.1). With the aim of applying DBOV as fluorophore for bioimaging, we have been working on syntheses of water-soluble DBOVs and introduction of functional groups to be used for bioconjugation.  

3.2 On-Surface Synthesis of Graphene Nanoribbons 

While infinite graphene does not have a bandgap and thus cannot be used as a semiconductor, graphene nanoribbons (GNRs) typically narrower than 10 nm can have bandgaps that render them interesting semiconductor materials. Moreover, it has been revealed that the electronic properties of GNRs are defined by their width and edge structures, and unique quantum electronic properties can also be induced by specific chemical structures of GNRs. For the synthesis of GNRs with atomically precise structures, the so-called bottom-up synthesis on metal surfaces under ultrahigh vacuum has emerged in the last decade, based on tailor-made organic molecules as precursors that undergo polymerization and planarization into GNRs by thermal treatments (cf. publication 2 in 4.1). We have explored new molecular precursors for the on-surface synthesis of unique GNRs in collaboration with Prof. Roman Fasel. For example, we have synthesized 8,8'-dibromo-5,5'-bibenzo[rst]pentaphene as a new monomer in an attempt to synthesize N = 8 armchair GNRs, which are theoretically predicted to have a very small bandgap. Unfortunately, this monomer failed to afford the desired GNR, but still provided novel GQDs with a combination of zigzag and armchair edges, namely dibenzohexacenohexacene and dibenzopentaphenoheptaphene (publication in FY2020). On the other hand, we have considered a use of the on-surface cyclization of methyl groups, forming five-membered rings (see publication 13 in 4.1), for syntheses of unprecedented GNRs extended with five-membered rings. To this end, we have synthesized several different precursors having o-tolyl groups, which are expected to give indeno-fused GNRs that have incorporated five-membered rings. On-surface synthesis using these precursors will be carried out during FY2020. 


4. Publications

4.1 Journals

  1. A. Riss, M. Richter, A. P. Paz, X.-Y. Wang, R. Raju, Y. He, J. Ducke, E. Corral, M. Wuttke, K. Seufert, M. Garnica, A. Rubio, J. V. Barth, A. Narita, K. Müllen, R. Berger, X. Feng, C.-A. Palma, W. Auwarter, Polycyclic aromatic chains on metals and insulating layers by repetitive [3+2] cycloadditions. Nat. Commun. 2020, 11, 1490.
  2. X. Xu, K. Müllen,* A. Narita,* Syntheses and Characterizations of Functional Polycyclic Aromatic Hydrocarbons and Graphene Nanoribbons. Bull. Chem. Soc. Jpn. 2020, 93, 490-506. (BCSJ Diamond Collection: Frontiers of Molecular Science; Life Chemistry)
  3. M. Di Giovannantonio, A. Keerthi, J. I. Urgel, M. Baumgarten, X. Feng, P. Ruffieux, A. Narita, R. Fasel, K. Müllen, On-Surface Dehydro-Diels–Alder Reaction of Dibromo-bis(phenylethynyl)benzene. J. Am. Chem. Soc. 2020, 142, 1721-1725.
  4. Q. Chen, D. Schollmeyer, K. Müllen,* A. Narita,* Synthesis of Circumpyrene by Alkyne Benzannulation of Brominated Dibenzo[hi,st]ovalene. J. Am. Chem. Soc. 2019, 141, 19994-19999.
  5. I. C.-Y. Hou, A. Narita,* K. Müllen,* Stepwise Lateral Extension of Phenyl-Substituted Linear Polyphenylenes. Macromol. Chem. Phys. 2019, 221, 1900374. (Special issue: 100 Years of Macromolecular Chemistry; Seleted for Front Cover)
  6. X. Liu, S.-Y. Chen, Q. Chen, X. Yao, M. Gelleri, S. Ritz, S. Kumar, C. Cremer, K. Landfester, K. Müllen, S. H. Parekh, A. Narita, M. Bonn, Nanographenes: Ultrastable, Switchable, and Bright Probes for Super-Resolution Microscopy. Angew. Chem. Int. Ed. 2020, 59, 496-502.
  7. Q. Sun, I. C.-Y. Hou, K. Eimre, C. A. Pignedoli, P. Ruffieux, A. Narita,* R. Fasel,* On-surface synthesis of polyazulene with 2,6-connectivity. Chem. Commun. 201955, 13466-13469.
  8. P. Fantuzzi, A. Candini, Q. Chen, X. Yao, T. Dumslaff, N. Mishra, C. Coletti, K. Müllen, A. Narita, M. Affronte, Color Sensitive Response of Graphene/Graphene Quantum Dot Phototransistors. J. Phys. Chem. C 2019123, 26490-26497.
  9. Q. Chen, S. Thoms, S. Stöttinger, D. Schollmeyer, K. Müllen,* A. Narita,* T. Basché,* Dibenzo[hi,st]ovalene as Highly Luminescent Nanographene: Efficient Synthesis via Photochemical Cyclodehydroiodination, Optoelectronic Properties, and Single-Molecule Spectroscopy. J. Am. Chem. Soc. 2019141, 16439-16449.
  10. Q. Chen, W. Zajaczkowski, J. Seibel, S. De Feyter, W. Pisula,* K. Müllen,* A. Narita,* Synthesis and helical supramolecular organization of discotic liquid crystalline dibenzo[hi,st]ovalene. J. Mater. Chem. C 2019, 7, 12898-12906. (Invited contribution to themed collection: Journal of Materials Chemistry C Emerging Investigators; selected for inside front cover)
  11. M. Wuttke, Z. Liu, H. Lu, A. Narita,* K. Müllen,* Direct Metal‐Free Chemical Vapor Deposition of Graphene Films on Insulating Substrates for Micro‐Supercapacitors with High Volumetric Capacitance. Batteries Supercaps2019, 2, 929-933. (Special collections: 2D Energy Storage Materials; Selected for Front Cover)
  12. Y. Hu, G. M. Paternò, X.-Y. Wang, X.-C. Wang, M. Guizzardi, Q. Chen, D. Schollmeyer, X.-Y. Cao, G. Cerullo, F. Scotognella, K. Müllen,* A. Narita,* π-Extended Pyrene-Fused Double [7]Carbohelicene as a Chiral Polycyclic Aromatic Hydrocarbon. J. Am. Chem. Soc. 2019141, 12797-12803.
  13. M. Di Giovannantonio,* K. Eimre, A. V. Yakutovich, Q. Chen, S. Mishra, J. I. Urgel, C. A. Pignedoli, P. Ruffieux, K. Müllen, A. Narita,* R. Fasel,* On-Surface Synthesis of Antiaromatic and Open-Shell Indeno[2,1-b]fluorene Polymers and Their Lateral Fusion into Porous Ribbons. J. Am. Chem. Soc. 2019141, 12346-12354.
  14. I. C.-Y. Hou, V. Diez-Cabanes, A. Galanti, M. Valášek, M. Mayor, J. Cornil, A. Narita,* P. Samorì,* K. Müllen,* Photomodulation of Two-Dimensional Self-Assembly of Azobenzene? Hexa-peri-hexabenzocoronene-Azobenzene Triads. ChemMater201931, 6979-6985. (Special issue: Professor Jean-Luc Bredas Festschrift)
  15. J. I. Urgel, M. Di Giovannantonio, G. Gandus, Q. Chen, X. Liu, H. Hayashi, P. Ruffieux, S. Decurtins, A. Narita, D. Passerone, H. Yamada, S.-X. Liu, K. Müllen, C. A. Pignedoli, R. Fasel, Overcoming Steric Hindrance in Aryl‐Aryl Homocoupling via On‐Surface Copolymerization. ChemPhysChem 201920, 2360-2366. (Special Issue: On‐Surface Synthesis)
  16. K. Xu, J. I. Urgel, K. Eimre, M. Di Giovannantonio, A. Keerthi, H. Komber, S. Wang, A. Narita, R. Berger, P. Ruffieux, C. A. Pignedoli, J. Liu, K. Müllen, R. Fasel, X. Feng, On-Surface Synthesis of a Nonplanar Porous Nanographene. J. Am. Chem. Soc. 2019141, 7726-7730.
  17. Q. Zhong, Y. Hu, K. Niu, H. Zhang, B. Yang, D. Ebeling, J. Tschakert, T. Cheng, A. Schirmeisen, A. Narita,* K. Müllen,* L. Chi,* Benzo-Fused Periacenes or Double Helicenes? Different Cyclodehydrogenation Pathways on Surface and in Solution. J. Am. Chem. Soc. 2019141, 7399-7406.

Articles without peer-review

  1. 成田明光, グラフェンナノリボンの前駆体設計と構造制御, 応用物理, 2019, 88, 608. (A. Narita, Precursor design for bottom-up synthesis of graphene nanoribbons, OYO BUTURI, 2019, 88, 608)
  2. 成田明光, カーボン系高分子のボトムアップ合成, 高分子, 2019, 68, 294-296. (A. Narita, Bottom-Up Synthesis of Graphene Nanoribbons as Structurally Well-Defined, Quasi-One-Dimensional Carbon Materials, Polymers, 2019, 68, 294?296.)

4.2 Books and other one-time publications

Nothing to report

4.3 Oral and Poster Presentations

Invited Talks at Conferences and Symposiums

  1. Narita, A. Bottom-up synthesis of atomically precise graphene quantum dots. International Conference Nano-M&D 2019, “Properties, Fabrication and Applications of Nano-Materials and Nano-Devices”, Savoy Beach Hotel, Paestum, Italy, June 4–8, 2019.
  2. Narita, A. Bottom-up molecular synthesis of atomically precise graphene nanoribbons and quantum dots,” Graphene & Co Annual Meeting 2019, Bad Herrenalb, Germany, October 27–30, 2019.
  3. Narita, A. Bottom-up Chemical Synthesis of Atomically Precise Graphene Nanostructures. The 81st Okazaki Conference "Forefront of Measurement Technologies for Surface Chemistry and Physics in Real-Space, k-Space, and Real-Time", Okazaki Conference Center, Japan, December 2–4, 2019.
  4. Narita, A. Synthesis and Characterizations of Highly Π-extended Conjugated Polymers as Graphene Nanoribbons.The 16th Pacific Polymer Conference. The Suntec Singapore Convention and Exhibition Centre, Singapore, December 8–12, 2019.
  5. Narita, A. Bottom-up Molecular Synthesis of Atomically Precise Graphene Nanoribbons and Quantum Dots, MANA International Symposium 2020 Jointly with ICYS, Tsukuba International Congress Center EPOCHAL TSUKUBA, Tsukuba, Japan, March 1–4, 2020 (cancelled due to Covid-19).
  6. Narita, A. Bottom-up Synthesis of Graphene Nanoribbons:  Precursor Design and Structural Control,” Medium and Long-Term Program Lecture, The 100th Annual Meeting of the Chemical Society of Japan, Noda Campus, Tokyo University of Science, Chiba, Japan, March 22–25, 2020 (cancelled due to Covid-19).

Contributed Talks

  1. Narita, A. Synthesis and Functionalizations of Dibenzo[hi,st]ovalene as Highly Luminescent Nanographene with Zigzag Edges.The 18th International Symposium on Novel Aromatic Compounds. Sapporo Convention Center, Sapporo, Japan, July 21–26, 2019.
  2. Narita, A. π拡張ラダーポリマー “グラフェンナノリボン” の合成 とその特異な電子物性,” 第1回ラダーポリマー研究会講演会, 東京工業大学大岡山キャンパス, Tokyo, Japan, December 27, 2019.


  1. Narita, A. Bottom-Up Molecular Synthesis of Structurally Defined Graphene Nanoribbons, Invited Seminar, Department Chemie, Universität zu Köln, Cologne, Germany, April 9, 2019.
  2. Narita, A. Bottom-up Synthesis of Atomically Precise Graphene Nanoribbons and Graphene Quantum Dots, Invited Seminar, Department of Chemistry, Graduate School of Science, Tohoku University, Sendai, Japan, June 24, 2019.
  3. Narita, A. Molecular Synthesis of Structurally Defined Graphene Nanoribbons and Quantum Dots with Unique Electronic and Optical Properties, CNC Young Investigator Seminar Series, Center for Nanosystems Chemistry, Julius Maximilian University of Würzburg, Germany, July 5, 2019.
  4. Narita, A. Bottom-Up Synthesis of Nanographene Molecules and Graphene Nanoribbons,” Center for Advancing Electronics Dresden (cfaed) & Department of Chemistry and Food Chemistry, Technical University of Dresden, Dresden, Germany, November 8, 2019.
  5. Narita, A. Bottom-up Molecular Synthesis of Atomically Precise Graphene Nanoribbons and Quantum Dots, MD-6 – Centre for Translational Medicine, National University of Singapore, Singapore, December 13, 2019.
  6. Narita, A. Synthesis of Functional Polycyclic Aromatic Hydrocarbons and Graphene Nanoribbons in Solution and on Surface, Wiley-VCH, Weinheim, Germany, January 20, 2020.
  7. Narita, A. Synthesis of Functional Polycyclic Aromatic Hydrocarbons and Graphene Nanoribbons in Solution and on Surface, Invited Seminar, Department of Advanced Materials Science, Graduate School of Frontier Sciences, Kashiwa Campus, The University of Tokyo, Kashiwa, Japan, February 25, 2020.
  8. Narita, A. Bottom-up Synthesis of Atomically Precise Graphene Nanoribbons and Graphene Quantum Dots, Center for Organic Photonics and Electronics Research (OPERA), Kyushu University, Fukuoka, Japan, February 27, 2020.

5. Intellectual Property Rights and Other Specific Achievements

Nothing to report

6. Meetings and Events


1st Workshop on Ladder Polymer Science

  • Date: July 14, 2019
  • Venue: OIST Campus Lab1 C016
  • Co-organizers and Speakers: 
    • Prof. Tomoyuki Ikai (Nagoya University)
    • Prof. Fumitaka Ishiwari (Tokyo Institute of Technology)
    • Prof. Hideto Ito (Nagoya University)
    • Prof. Akimitsu Narita (MPIP/OIST)


Japan-Germany-China Joint Workshop on Syntheses and Characterizations of Innovative Molecular and Quantum Materials

  • Date: July 16-17, 2019
  • Venue: OIST Campus Lab1 C016
  • Organizer: Akimitsu Narita (OIST)
  • Speakers:
    • Mr. Qiang Chen (Max Planck Institute for Polymer Research (MPIP), Germany)
    • Mr. Takahiro Doba (The University of Tokyo, Japan)
    • Mr. Ian Cheng-Yi Hou (MPIP, Germany)
    • Prof. Yunbin Hu (Central South University, China)
    • Prof.Akimitsu Narita(MPIP/OIST)
    • Prof. Yoshinori Okada (OIST)
    • Dr. Zijie Qiu (MPIP, Germany) 
    • Mr. Keitaro Yamamoto(Osaka University, Japan)
    • Mr. Xuelin Yao (MPIP, Germany)

7. Other

Prof. Akimitsu Narita joined the Inaugural Early Career Advisory Board for the Asian Journal of Organic Chemistry in January, 2020 (Asian J. Org. Chem. 20209, 6–7; highlighted in ChemistryViews).