Interaction between functionalized graphene and sulfur compounds in a lithium–sulfur battery – a density functional theory investigation

van der Waals attraction and formation of coordinate covalent Li-O bonds. The adsorption strength is dependent on the inter-layer distance and electron rich functional groups. Through these mechanisms, sulphur and lithium polysulfides can be successfully retained in porous graphene, leading to improved conductivity and charge transfer in the cathode of Li-S batteries.