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

Abstract

Abstract 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 MoS 2 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 Li 2Sn 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.