Invited talk

Carbon-based 1D and 2D Nanoarchitectures: insights from theory and experiments
Aran Garcia-Lekue

Donostia International Physics Center (DIPC), Donostia-San Sebastián 
Ikerbasque, Basque Foundation for Science, Bilbao

Nanostructuring graphene at the atomic scale is now possible by on-surface synthesis methods, which unite the sturdiness of covalently bonded networks with the easy tunability of molecular materials.[1,2] These experimental advances have boosted the research attempts to create novel 1D and 2D carbon-based structures aimed at the development of new nanoelectronic, spintronic or optoelectronic devices. However, before graphene nanostructures can be used in practical applications, an atomic level understanding and control of their properties is required. As such, ab-initio simulation has developed as an essential partner in the search of optimal carbon-based low dimensional materials.[3]

In this talk, I will present some studies of prototype graphene nanostructures, such as graphene nanoribbons (GNRs) and nanoporous graphene (NPG), that we have recently performed in our group. Using mainly density functional theory (DFT), and in collaboration with our experimental colleagues, we have investigated their structural, electronic, magnetic and transport properties. On the one hand, we have explored the emergence of localized spins in metallic GNRs realized by substitutionally doping a narrow band gap GNR with boron atoms in its interior.[4] We have also reported on a novel NPG structure, which can be envisioned as GNRs laterally fused by phenylene bridges. Interestingly, electron propagation simulations demonstrate the capability of modulating the interribon coupling by different degrees of freedom provided by the phenylene bridges.[5] Our results thus show that chemical doping offers the perspective of electronically controlling spins in 1D carbon nanoarchitectures, while molecular bridges emerge as an efficient tool to engineer quantum transport in 2D networks.

References
[1] Cai et al., Nature 466, 470 (2010)
[2] Moreno et al., Science 360, 199 (2018)
[3] Piquero-Zulaica et al., Nat. Commun. (just accepted)
[4] Friedrich et al., ACS Nano 16, 14819 (2022)
[5] Moreno et al., J. Am. Chem. Soc. 145, 8988 (2023)