First-principles insights into the performance of high-entropy MXene as the anode for lithium ion batteries

[Display omitted] •The adsorption and diffusion behavior of Li on high-entropy MXene surface was investigated based on first principles.•High entropy MXene had higher electrical conductivity and ion transport velocity.•The diffusion energy barrier of Li on high entropy MXene surface is small. High entropy MXene had four major effects, which had been widely studied in the field of cathode materials for lithium-ion batteries (LIBs). The enhancement of high entropy MXene's lithium storage performance was simply attributed to the cocktail effect or synergistic action of various metal elements, but the specific synergistic mechanism was still unclear. In this context, we used first-principal calculations to explore the effect of high entropy on the Li adsorption and diffusion on high-entropy MXene. We observed that (Ti0.25V0.25Nb0.25Mo0.25)2CO2 possessed higher electrical conductivity and ion transport velocity than other single-component MXene. Meanwhile, Li atom could be well adsorbed on the surface of MXene, and showed a low diffusion energy barrier (0.15 eV). Furthermore, the maximum possible capacity of high-entropy MXene was predicted to be 497 mAh/g, corresponding to 4 Li per unit cell. As a result, (Ti0.25V0.25Nb0.25Mo0.25)2CO2 should be a next generation anode material for LIBs.