Two-Dimensional Covalent Triazine Framework as a Promising Anode Material for Li-Ion Batteries

Presently, great attention is focused on the search for promising anode materials due to the rapid development of electronic products. In this study, by means of density functional calculations, we have predicted that a bilayer covalent triazine framework (CTF) may be a promising anode material for rechargeable lithium-ion batteries (LIBs). Our calculations reveal that lithium atoms can be preferably inserted into the interlayer spacing of the bilayer CTF. The calculations indicate charge transfer from Li atoms to the bilayer CTF. After lithium adsorption, the bilayer CTF undergoes a transition from a semiconductor to a metal, ensuring good electrical conductivity of the electrode material. Furthermore, the bilayer CTF can achieve a high theoretical specific capacity of 925.99 mAh/g and a moderately low diffusion barrier of 0.65 eV. Our calculated average open-circuit voltages (OCVs) lie in the range of 1.58-0.51 V, which are in between those of some typical anode materials. All of these calculations suggest that the bilayer CTF can be used as a potential anode material for LIBs.