Hierarchical mesoporous SnO2 nanosheets on carbon cloth toward enhancing the polysulfides redox for lithium–sulfur batteries

Abstract

Lithium–sulfur (Li–S) batteries have been acknowledged as outstanding substitutes for energy storage systems due to their superiority in energy density. To satisfy the commercial applications, it's necessary to establish the highly efficient and long-life Li–S batteries by synchronously restraining the shuttle effect and enhancing the polysulfides redox. Here, we prepared hierarchical mesoporous SnO₂ nanosheets on carbon nanofibers (CNFs) namely C@SnO₂ with the novel topological method. The obtained C@SnO₂ materials not only show the strong chemisorption to trap polysulfides but also can more effectively decrease the electrochemical polarization to enhance the polysulfides redox. With the 3D conductive framework CNFs as the current collector, the hierarchical C@SnO₂/S nanosheets material electrode delivered a specific capacity of 1228 mA h g⁻¹ at 0.2C and retained a stable cycling performance at 2C over 1000 cycles with the decay as low as ≈0.024% per cycle.