Theoretical study on the effect of shear deformation on MoTe₂ as cathode material for calcium ion batteries

In this study, the electronic structure and diffusion barrier of Ca adsorbed MoTe₂ system under different degrees of shear deformation were calculated based on the first-principles method. The results show that both the pure MoTe₂ system and Ca-adsorbed MoTe₂ system are affected by shear deformation. The pure MoTe₂ undergoes a transition from direct to indirect band gap under shear deformation. The adsorption of Ca makes MoTe₂ changes from semiconductor to quasi-metal. The results of the density of states show that Ca insertion makes the conduction band part of the adsorption system significantly enhanced. The diffusion barrier of Ca through MoTe₂ indicates that the shear deformation promotes the diffusion of Ca on the surface of MoTe₂. Shear deformation can effectively modulate the electronic properties of the MoTe₂ system, which provides a theoretical basis for the application of MoTe₂ materials in the field of ion batteries.

In this study, Materials Studio 8.0 software was used to construct the MoTe₂ model and Ca adsorbed MoTe₂ model, and the CASTEP module was used for first-principles calculation.