Defect-Mediated Lithium Adsorption and Diffusion on Monolayer Molybdenum Disulfide

Area of Science:

• Materials Science
• Electrochemistry
• Computational Chemistry

Background:

• Monolayer molybdenum disulfide (MoS2) is explored as a high-capacity anode material for lithium-ion batteries.
• Understanding lithium ion interactions with MoS2, especially with defects, is crucial for optimizing battery performance.

Purpose of the Study:

• To investigate the adsorption and diffusion of lithium on pristine and defective monolayer MoS2 using first-principles calculations.
• To evaluate the impact of various defects (vacancies, antisite, grain boundary) on lithium binding and mobility.

Main Methods:

• Spin density functional theory (DFT) calculations were employed.
• Adsorption energies and diffusion barriers for lithium on defective MoS2 were computed.

Main Results:

• Defects significantly increased lithium adsorption energies on MoS2, ranging from 2.81 to 3.80 eV.
• Lithium binding enhancement is attributed to Li 2s electron donation to defect sites.
• Lithium diffusion energy barriers remained low (0.25–0.42 eV), indicating unaffected mobility.

Conclusions:

• Defective monolayer MoS2 exhibits enhanced lithium binding, making it a promising anode material.
• The material's suitability for lithium-ion batteries is supported by strong adsorption and maintained diffusion kinetics.