Transition Metal Layer Substitution in Mo₂CS₂ MXene for Improving Li Ion Surface Kinetics

Area of Science:

• Materials Science
• Computational Chemistry
• Electrochemistry

Background:

• MXenes, particularly Mo2CS2, are explored for energy storage applications.
• Lithium-ion mobility is crucial for battery performance.
• Understanding ion adsorption and migration on 2D materials is key for developing advanced batteries.

Purpose of the Study:

• To investigate lithium ion adsorption and mobility on Mo2CS2 MXene surfaces.
• To explore the effect of Vanadium (V) substitution for Molybdenum (Mo) on Li+ mobility.
• To assess the potential of modified MXenes as anode materials for Li-ion batteries.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Simulations focused on Li+ adsorption energies and migration pathways.
• Electronic structure and metallic character were analyzed.

Main Results:

• Mo2CS2 exhibits specific Li+ adsorption sites and migration barriers.
• Substituting Mo with V in the upper layer (forming MoVCS2) dramatically improves Li+ mobility by up to 95%.
• The MoVCS2 material maintains its essential metallic conductivity.

Conclusions:

• Vanadium substitution in Mo2CS2 MXene is a viable strategy to enhance Li+ mobility.
• MoVCS2 demonstrates excellent potential as a conductive anode material for high-performance Li-ion batteries.
• Reduced Li+ migration barriers in MoVCS2 are critical for efficient charge transfer.