S-Functionalized Mo2C Monolayer as a Novel Electrode Material in Li-Ion Batteries

First-principles calculations have been performed to calculate the electrochemical properties of the S-functionalized Mo2C (Mo2CS2) monolayer using the projected-augmented wave (PAW) method based on density functional theory (DFT). The geometrical optimization reveals that the Li gets favorably adsorbed on the top of the Mo layer. The metallic nature of S-functionalized Mo2C maintains its electronic conduction with and without Li adsorption, which reflects its special role in Li-ion battery technologies. Functionalization of S-atoms significantly increases the Li-adsorption energy in the resultant monolayer which consequently alters the charge storage capacity of Li-ion batteries (LIBs). The calculated low diffusion barrier (∼0.22 eV) of adsorbed Li ion implies the high mobility and cyclic ability of Mo2CS2 monolayer. Moreover, the calculated theoretical specific capacity, 410 mA h g–1, and average voltage, 0.3 V, suggest its application as a proficient anode material in LIBs.