Strain-engineered atomic-scale lithium kinetics in 2D 1T-NiS₂ monolayers

The recently discovered semiconducting T-phase nickel disulfide (NiS₂) monolayer has emerged as a promising electrode material candidate. However, optimizing its ionic diffusion kinetics by mechanical strains remains a critical challenge requiring further investigation. In this study, we systematically investigated the effects of large in-plane biaxial strains on Li-ion diffusion mechanisms in NiS₂ monolayers through first-principles calculations. By introducing in-plane biaxial strains, it demonstrated that both adsorption strength and diffusion dynamics of Li ion were simultaneously reshaped through coordinated charge transfer reconfiguration between Li ion and substrate and the detailed electronic structure analysis. This synergistically helps to strengthen the Li adsorption and lower ionic migration resistance. The proposed mechanism based on the present findings opens the mechanical avenues and provides fundamental insights for dynamic performance tuning in lithium battery technologies.