Journal:European Journal of Inorganic Chemistry

Key Words:density functional theory · lithium-sulfur batteries · iron-based compounds · adsorption energy

Abstract:Li-S batteries (LSBs) are considered as the attractive candidates
for next-generation high-energy system due to their high
energy and low cost. However, their practical application is
hindered by several stubborn issues, including the poor electric
conductivity of sulfur cathodes, the shuttle of lithium polysulfides
(LiPSs) and the slow dynamics during charge/discharge
cycles. Transitional iron (Fe)-based compounds are regarded as
effectively electrocatalysts for polysulfide conversion by accelerating
the reaction kinetics and enhancing the electric
conductivity and electron/charge transfer. In this study, we
investigate the typical transition Fe-based compounds (Fe3X,
X=B, C, N), known for their high catalytic ability, analyze their
roles as sulfur host for LSBs using density functional theory
(DFT). Our finding reveals that Fe3C and Fe3B surfaces exhibit
more Fe-S bonds compared to Fe3N surface, which explains the
different electrochemical behaviors observed during battery
testing with sulfur cathodes. Additionally, Fe3N demonstrates
greater structural stability and effective polysulfide adsorption
according to DFT calculations, outperforming the other two
compounds in these aspects. We believe that this theoretical
investigation would guide the identification of highly efficient
hosts for sulfur cathodes and open new avenues for sulfur host
selection in LSBs.

Indexed by:Journal paper

Document Code:e202400002

Discipline:Natural Science

Volume:27

Translation or Not:no

Date of Publication:2024-06-12

Included Journals:SCI