Ɣ-Graphyne as a possible candidate for Li+, Na+, and K+ metal ion battery anode

A systematic theoretical study employing Density Functional Theory (DFT) approaches has been conducted to investigate the interaction of alkali ions Li⁺, Na⁺, and K⁺ with the GY surface. Interaction energies, charge transfer mechanisms, and cell voltage values were modeled using high-level DFT calculations with the cam-B3LYP and PBE functionals. Both cluster and periodic boundary condition models were employed to provide a more comprehensive understanding of the phenomena under investigation. This combined approach leverages the strengths of both models, offering a deeper insight into the structural.

and electronic properties of the material. Adsorption of each ion on the GY surface was examined at various positions, revealing a preference for adsorption at the center of the GY triangular structure, with calculated adsorption energies ranging from −2.98 to −1.69 eV. Notably, the periodic model yielded adsorption energies that were approximately 30–45 % higher (more stable) compared to the cluster model. Furthermore, our results demonstrate that the band gap energy can be tuned by varying the relative position of the ions with respect to the GY surface. Finally, an analysis of the cell voltage values was performed to evaluate the potential of the GY allotrope as an anode material for ion batteries.