title: Bottom-up synthesis of liquid-phase-processable graphene nanoribbons with near-infrared absorption.
abstract: Structurally defined, long (>100 nm), and low-band-gap (∼1.2 eV) graphene nanoribbons (GNRs) were synthesized through a bottom-up approach, enabling GNRs with a broad absorption spanning into the near-infrared (NIR) region. The chemical identity of GNRs was validated by IR, Raman, solid-state NMR, and UV-vis-NIR absorption spectroscopy. Atomic force microscopy revealed well-ordered self-assembled monolayers of uniform GNRs on a graphite surface upon deposition from the liquid phase. The broad absorption of the low-band-gap GNRs enables their detailed characterization by Raman and time-resolved terahertz photoconductivity spectroscopy with excitation at multiple wavelengths, including the NIR region, which provides further insights into the fundamental physical properties of such graphene nanostructures.
authors.affiliation: Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany.
authors.forename: Akimitsu
authors.initials: A
authors.lastname: Narita
authors.forename: Ivan A
authors.initials: IA
authors.lastname: Verzhbitskiy
authors.forename: Wout
authors.initials: W
authors.lastname: Frederickx
authors.forename: Kunal S
authors.initials: KS
authors.lastname: Mali
authors.forename: Soeren Alkaersig
authors.initials: SA
authors.lastname: Jensen
authors.forename: Michael Ryan
authors.initials: MR
authors.lastname: Hansen
authors.forename: Mischa
authors.initials: M
authors.lastname: Bonn
authors.forename: Steven
authors.initials: S
authors.lastname: De Feyter
authors.forename: Cinzia
authors.initials: C
authors.lastname: Casiraghi
authors.forename: Xinliang
authors.initials: X
authors.lastname: Feng
authors.forename: Klaus
authors.initials: K
authors.lastname: Müllen
keywords: Diels−Alder reaction; band-gap engineering; cyclodehydrogenation; graphene nanoribbon; near-infrared absorption