Li adsorption and diffusion on the surfaces of molybdenum dichalcogenides MoX₂ (X = S, Se, Te) monolayers for...

We study some of the most high performance electrode materials for lithium-ion batteries. These comprise molybdenum dichalcogenide MoX₂ (molybdenum disulfide MoS₂, molybdenum diselenide MoSe₂, molybdenum ditelluride MoTe₂). The stability is studied by calculating cohesive energy and formation energy. Structural, electronic, and electrical properties are well defined, and these structures show a direct gap. Lithium adsorption at different sites, theoretical storage capacity, and lithium diffusion path are determined. Our study findings suggest that the adsorption of Li on the preferred site on the surface of the MoX₂ monolayer maintains its semiconductor behavior. Comparing the activation energy barrier of these structures with other monolayers such as graphene or silicene, we found that MoX₂ shows low lithium diffusion energy and good storage capacity, which indicates that the MoX₂ is well suited as an anode material for lithium-ion batteries. Our research can offer new ideas for experimental and theoretical design and new anode materials for lithium-ion batteries (LIB).

The studies were performed with Quantum ESPRESSO package based on density functional theory (DFT), plane waves, and pseudopotentials (PWSCF) to calculate the physical properties of MoX₂ (X = S, Se, Te), lithium adsorption, and diffusion on their surfaces and the storage capacity of these structures. The BoltzTraP code is used to calculate thermoelectric properties.