A novel method for synthesis of γ-graphyne and their charge transfer properties

Graphyne represents a family of layered artificial carbon allotropes wherein both sp and sp2 hybridized carbon atoms coexist in the lattice with γ-graphyne being the most stable member of the group. Theoretical studies predict γ-graphyne has high carrier mobility (104–105 cm2V−1s−1), exceptional flexibility, low thermal conductance, and charge transport comparable to graphene with a monolayer bandgap of ∼2.23eV. At present experimental exploration of γ-graphyne is still impeded due to the lack of suitable synthesis techniques. We report a simple one-pot Sonogashira cross-linking strategy for the synthesis of pristine γ-graphyne under mild conditions with high yields. As synthesized product was of high purity and exhibited a bandgap of 2.3eV. We believe this synthetic strategy will be helpful in designing similar strategies for the experimental realization of other members of this family. Charge transfer is a fundamental process for understanding a material's properties and tailoring them for various electronic and optoelectronic applications. In this work, UV–visible absorption studies were carried out to understand the charge transfer behavior and defect density of γ-graphyne with donor/acceptor molecules wherein few-layered γ-graphyne showed a comparable/better charge transfer behavior with organic acceptor molecules (TCNQ) than few-layered graphene.