Graphdiyne and derivatives with delocalized π-electron systems are of particular interest owing to their structural, electronic, and transport properties, which are important for potential applications in next-generation electronics. Inspired by recently obtained extended graphdiyne nanowires, explorations of the modulation of the band gap and carrier mobility of this new species are still needed before application in device fabrication. To provide a deeper understanding of these issues, herein we present theoretical studies of one-dimensional extended graphdiyne nanowires using first-principle calculations. Modulation of the electronic properties of the extended graphdiyne nanowire was investigated systemically by considering several chemical and physical factors, including electric field, chemical functionalization, and carbo-merization. The band gap was observed to increase upon application of an electric field parallel to the plane of the synthesized graphdiyne nanowire in a non-periodic direction. Although chemical functionalization and carbo-merization caused the band gaps to decrease, the semiconducting property of the nanowires was preserved. Band gap engineering of the extended graphdiyne nanowires was explored regarding the field strength and the number of -C≡C- units in the carbon chain fragments. The charge carrier mobility of chemically functionalized and carbo-merized extended graphdiyne nanowires was also calculated to provide a comparison with pristine nanowire. Moreover, crystal orbital analysis was performed in order to discern the electronic and charge transport properties of the extended graphdiyne nanowires modified by the aforementioned chemical and physical factors.
Keywords: band gap engineering; carrier mobility; density functional theory; graphdiyne; nanomaterials.