Enhanced electrochemical and thermal transport performance of Graphene/MoS₂ heterostructures for lithium ion battery: multi-scale modeling

Graphene/molybdenum disulfide (Gr/MoS₂) composites have exhibited superb electrochemical performance in lithium ion batteries (LIBs), yet the mechanisms have not been well studied. Here, we adopt multi-scale modeling to investigate the enhanced electrochemical and thermal transport properties of Gr/MoS₂ heterostuctures. The calculated electronic structures demonstrated the greatly improved electrical conductivity of Gr/MoS₂ heterostructures than pure MoS₂ monolayers by the addition of graphene. With the increase of graphene concentration, graphene layers not only further improve the electrical conductivity, but also significantly stabilize the Li atoms in heterostructures. The calculated thermal conductivity form large scale molecular dynamic simulations manifested that the Gr/MoS₂ heterostructures could achieve a much higher in-plane thermal conductivity compared to pure MoS₂, which may accelerate the heat conduction from the electrode to the ambient, inducing excellent battery performances. Our findings not only shed light on the mechanisms of the enhanced electrochemical and thermal transport properties of Gr/MoS₂ heterostructures, but also suggest how to design advanced Gr/MoS₂ composites for LIBs.