Capture and catalytic conversion of lithium polysulfides by metal-doped MoS2 monolayers for lithium–sulfur batteries: A computational study

Searching for effective anchoring material to capture and convert lithium polysulfides (Li2Sn) for suppressing their shuttling effects has been a key scientific issue for the development of lithium sulfur (Li–S) batteries with high-efficiency. Herein, by means of density functional theory (DFT) computations, we have explored the potential of doped MoS2 monolayers with a series of metal atoms in place of Mo or S atom as the anchoring materials for Li–S batteries. Our results revealed that Li2Sn species can be physisorbed on doped MoS2 monolayer by substituting Mo atom with metal dopant, inducing a limited enhancement for the immobilization of Li2Sn species, as compared with pristine MoS2 monolayer. In contrast, due to the synergistic effects between metal dopant and its adjacent S atoms, the substitution in S atom with metal dopant greatly improves the binding strength of Li2Sn species on MoS2 monolayer, particularly saving the intact Li2Sn configuration. More interestingly, this kind of metal-doped MoS2 monolayer exhibits good catalytic activity for the formation and the decomposition of Li2S in discharge and charge processes. Thus, metal-doped MoS2 monolayers can be utilized as the multifunctional anchoring materials for Li–S batteries by carefully controlling the kinds and sites of dopants in MoS2 monolayer, which opens up a new strategy to further develop high-performance Li–S batteries. Metal doping can greatly enhance the capture and conversion of Li2Sn species in Li–S batteries on MoS2 monolayer by carefully controlling the kinds and sites of metal dopants. [Display omitted] •Introducing dopants can enhances the anchoring effect of Li2Sn species on MoS2 monolayer in various ways.•The integrity of Li2Sn species can be well saved after anchored on metal-doped MoS2 monolayer.•Doped MoS2 monolayers exhibit good catalytic activity for the formation and the decomposition of Li2S species.