Graphdiyne: A promising anode material for lithium ion batteries with high capacity and rate capability

We have carried out first-principles calculations to explore the energetics and dynamics of Li in graphdiyne monolayers. The porous structure of graphdiyne enables both in-plane and out-plane diffusion of Li ions with moderate barriers, 0.35-0.52 eV. A unique Li occupation pattern named as a triangular pattern is identified, with Li atoms occupying three symmetric sites in the triangular-like pores. Based on this occupation pattern, the Li storage capacity of single-layer graphdiyne can be as high as LiC₃, which is twice the capacity of commonly used graphite (LiC₆). With high Li mobility and high storage capacity, this experimentally available porous carbon material is expected to find applications in efficient lithium storage.