The commercialization of lithium-sulfur (Li-S) batteries is crippled due to lithium polysulfides (LiPSs) dissolution into the electrolyte and the poor kinetics of their reversible conversions. The graphene-based materials have been widely used as a conductive matrix, however, the apolar nature of the graphene provides insufficient binding required for the containment of the LiPSs within the cathode material. In this regard, the transition metal dichalcogenides exhibit great promise as anchoring materials (AMs) due to their capability of strong adsorption to LiPSs thus suppression of the polysulfides shuttles. In this study, we used first-principles based density functional theory (DFT) calculations to investigate the chemical interactions such as binding energies and catalytic activities between AMs such as tungsten dichalcogenides, WX_2 (X=S, Se, and Te) and the LiPSs. We found that the WX_2 possesses moderate binding strength to the LiPSs which is desired for effective anchoring. We perform an in-depth analysis of charge transfer and the electronic density of states to elucidate the underlying mechanisms that dictate the binding behavior of LiPSs and WX_2. The catalytic activity of WX_2 for the delithiation of the lower-order polysulfides are demonstrated through the reduction of the reaction barriers compared to the apolar AMs. Overall, our simulation results provide detailed insight into the behavior of WX_2 as AMs to suppress the LiPSs migration and increase the kinetics of LiPSs conversion reactions, henceforth paves the way towards the development of high-performance Li-S batteries.
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