Mesoscale Evaluation of Titanium Silicide Monolayer as a Cathode Host Material in Lithium–Sulfur Batteries Academic Article uri icon

abstract

  • © 2017, The Minerals, Metals & Materials Society. Two-dimensional materials are competitive candidates as cathode materials in lithium–sulfur batteries for immobilizing soluble polysulfides and mitigating the shuttle effect. In this study, a mesoscale modeling approach, which combines first-principles simulation and kinetic Monte Carlo simulation, is employed to evaluate titanium silicide (Ti 2 Si and TiSi 2 ) monolayers as potential host materials in lithium–sulfur batteries. It is found that the Ti 2 Si monolayer has much stronger affinities to Li 2 S x (x = 1, 2, 4) molecules than does the TiSi 2 monolayer. Also, Ti 2 Si can facilitate the dissociation of long-chain Li 2 S 4 to LiS 2 . On the other hand, TiSi 2 can only provide a weak chemical interaction for trapping soluble Li 2 S 4 . Therefore, the Ti 2 Si monolayer can be considered to be the next-generation cathode material for lithium–sulfur batteries. Nevertheless, the strong interaction between Ti 2 Si and Li 2 S also causes fast surface passivation. How to control the Li 2 S precipitation on Ti 2 Si should be answered by future studies.

author list (cited authors)

  • Liu, Z., Balbuena, P. B., & Mukherjee, P. P.

citation count

  • 6

publication date

  • June 2017

published in

  • JOM  Journal