RESUMEN
Graphene nanoribbons (GNRs), quasi-one-dimensional strips of graphene, exhibit a nonzero bandgap due to quantum confinement and edge effects. In the past decade, different types of GNRs with atomically precise structures have been synthesized by a bottom-up approach and have attracted attention as a novel class of semiconducting materials for applications in electronics and optoelectronics. We report the large-scale, inexpensive growth of high-quality oxygen-boron-oxygen-doped chiral GNRs with a defined structure using chemical vapor deposition. For the first time, a regular 2D self-assembly of such GNRs has been demonstrated, which results in a unique orthogonal network of GNRs. Stable and large-area GNR films with an optical bandgap of â¼1.9 eV were successfully transferred onto insulating substrates. This ordered network structure of semiconducting GNRs holds promise for controlled device integration.
RESUMEN
Structurally well-defined graphene nanoribbons (GNRs) have emerged as highly promising materials for the next-generation nanoelectronics. The electronic properties of GNRs critically depend on their edge topologies. Here, we demonstrate the efficient synthesis of a curved GNR (cGNR) with a combined cove, zigzag, and armchair edge structure, through bottom-up synthesis. The curvature of the cGNR is elucidated by the corresponding model compounds tetrabenzo[a,cd,j,lm]perylene (1) and diphenanthrene-fused tetrabenzo[a,cd,j,lm]perylene (2), the structures of which are unambiguously confirmed by the X-ray single-crystal analysis. The resultant multi-edged cGNR exhibits a well-resolved absorption at the near-infrared (NIR) region with a maximum peak at 850 nm, corresponding to a narrow optical energy gap of â¼1.22 eV. Employing THz spectroscopy, we disclose a long scattering time of â¼60 fs, corresponding to a record intrinsic charge carrier mobility of â¼600 cm2 V-1 s-1 for photogenerated charge carriers in cGNR.