Predicted superconductivity and underlying mechanism at alkali-metal/graphyne 2D interface

The development of metal-doped graphene superconductors is hindered by low doping efficiency and limited dopant variety. To explore potential solutions, we leverage the intrinsic nanoporous architecture of graphyne to theoretically model a new class of 2D superconductors. Computational results suggest that the periodic pores in the graphyne framework could serve as high-efficiency diffusion channels, potentially enhancing intercalation kinetics and doping efficiency. By investigating various alkali metal dopants (Li, Na, K, Rb) and concentrations, we identify a stable Li₃C₁₂ configuration in a Li-deposited γ-graphyne monolayer. This material is predicted to exhibit a superconducting transition temperature (T_c) of up to 27.7 K at ambient pressure, which would significantly surpass existing graphene-based counterparts if realized. The underlying mechanism is attributed to the presence of flat bands near the Fermi level, which significantly enhance the electron–phonon coupling interaction. These findings suggest that graphyne is a promising substrate for developing 2D carbon-based superconductors and provide theoretical insights into the functional applications of graphyne-based architectures.