Optical Properties of 3-Armchair Graphene Nanoribbons Produced by a Combination of Chemical Vapor Deposition with a Bottom-up Approach

Narrow graphene nanoribbons (GNRs) with atomically precise structure are interesting nanomaterials promising in various applications like optoelectronics, nanoelectronics, and photonics. The GNRs optical properties are barely studied due to the difficulty of their production. Herein, a new bottom-up method based on chemical vapor deposition to scale up the production of 3-armchair GNRs (3-AGNRs) under low vacuum on common Ni foil is reported. The Raman study confirms the structure and high quality of the produced GNRs. The wide optical bandgap of 3-AGNRs is demonstrated based on UV-Vis-IR absorption and photoluminescence (PL). Bright PL is observed in the blue spectral range with the characteristic features of 3-AGNRs located at 430 and 456 nm. The PL excitation spectral maps are presented, containing multiple spectrum features associated with GNRs. The demonstrated results can be helpful for unveiling the optical properties of atomically precise GNRs and can be beneficial for applications of GNRs.