Physikalische Chemie - Direktor: Prof. Dr. Martin Wolf
Special Seminar
Host: T. Kumagai

Monday, September 3, 2018, 11:00 am
PC Seminar Room, G 2.06, Faradayweg 4
Dr. Akimitsu Narita
Synthetic Chemistry Department, Max Planck Institute for Polymer Research, Mainz
Bottom-up Chemical Synthesis of 
Atomically Precise Graphene Nanostructures
Whereas graphene, namely isolated monolayer of graphite, demonstrate exceptional electronic and mechanical properties, its lack of bandgap prohibits its applications as an active semiconductor material.1 In contrast, graphene nanostructures such as graphene quantum dots (GQDs) and graphene nanoribbons (GNRs) possess open energy gaps, and are promising for nanoelectronic and (opto)electronic applications.1–3 The properties of such nanoscale graphenes are critically dependent on their size, morphology, and edge configuration, which makes it essential to precisely control their chemical structures. Although, the required precision cannot be achieved by “top-down” fabrication methods such as “cutting” of graphene, bottom-up chemical synthesis can achieve atomically precise GQDs and GNRs, either “in solution” by the conventional synthetic chemistry or “on surface” using the method of modern surface science.1–3 We have thus synthesized GQDs and GNRs with varying structures and properties, for example, achieving fine-tuning of the bandgap and incorporation of heteroatoms.1,3,4 We can also covalently functionalize the GNR edges with high accuracy, modulating the electronic properties and supramolecular behavior5 or inducing magnetic edge state.6 Moreover, dibenzo[hi,st]ovalene (DBOV) as a highly stable GQD showed strong red fluorescence, stimulated emission, and amplified spontaneous emission, making the promise for light emitting and lasing applications.7 These results highlight the high potential of such atomically precise graphene nanostructures for various applications, ranging from nanoelectronics and optoelectronic to spintronics and quantum computing.
X.-Y. Wang, A. Narita, K. Müllen, Nat. Rev. Chem. 2017, 2, 0100.
A. Narita, X. Feng, K. Müllen et al., Nature Chem. 2014, 6, 126.
A. Narita, X.-Y. Wang, X. Feng, K. Müllen, Chem. Soc. Rev. 2015, 44, 6616.
X.-Y. Wang, R. Fasel, K. Müllen, A. Narita et al., J. Am. Chem. Soc., 2018, 140, 9104.
A. Keerthi, K. Müllen, A. Narita et al., J. Am. Chem. Soc. 2017, 139, 16454.
M. Slota, A. Keerthi, A. Narita, K. Müllen, L. Bogani et al., Nature, 2018, 557, 691.
G. M. Paternò, K. Müllen, A. Narita, F. Scotognella et al., Angew. Chem. Int. Ed. 2017, 56, 6753.