MoS₂/Ti₂CT₂ (T = F, O) Heterostructures as Promising Flexible Anodes for Lithium/Sodium Ion Batteries

Flexible batteries play a more and more important role with the increasing demands of wearable electronics and soft robots, while searching for electrode materials with high stretchability remains a great challenge. In this work, we report that the heterostructures composed of MoS₂ and Ti₂CT₂ (T = F, O) monolayers are competitive and promising candidates as flexible anode materials for Li/Na ion batteries through first-principles calculations. Compared with the related single-layer components, MoS₂/Ti₂CT₂ heterostructures show more negative Li/Na adsorption energies and enhanced electrical conductivities. The theoretical capacities (over 430 mAh/g) are higher than that of the commercial anode material graphite, and the diffusion barriers are as low as 0.57 eV for Li and 0.37 eV for Na. Furthermore, MoS₂/Ti₂CT₂ heterostructures can sustain large ultimate tensile strains (>20%) and exhibit excellent mechanical flexibility.