Simulation of Ti2N and S/Se-functionalized Ti2N electrode in ion-batteries

MXenes have shown promising potential in rechargeable metal-ion batteries due to their electronic conductivity and mechanical stability. Functionalized Mxenes electrodes can affect the electrochemical performance of rechargeable metal-ion batteries. In this work, the potential use of Ti2N and S/Se-functionalized Ti2N as the electrode in Li, Na, and Ca Ion-batteries was systematically investigated by first-principle calculations. The results showed the metallic characteristics of Ti2N, Ti2NS2, and Ti2NSSe, ensuring proper electrical conductivity for fast electron transport. Moreover, Li, Na and Ca atoms can bind to both the surfaces of MXenes; such ion intercalation can reach up to multilayers for Na atoms in all cases. S-functionalization can further improve the results. Ti2NS2 showed a higher specific capacity for Li/Na as compared to other MXenes considered in this paper. Its specific capacity was 2 times higher than that of commercially used graphite (372 mAh center dot g(-1)). All cases show relatively low open circulate voltage and small diffusion barriers resulting in high performance of ion batteries. The findings of this study may pave the way for further experimental and theoretical studies on the application and design of MXenes-based 2D materials to reach high-efficiency rechargeable metal-ion batteries.