A functionalized graphene sheet-sulfur (FGSS) nanocomposite was synthesized as the cathode material for lithium-sulfur batteries. The structure has a layer of functionalized graphene sheets/stacks (FGS) and a layer of sulfur nanoparticles creating a three-dimensional sandwich-type architecture. This unique FGSS nanoscale layered composite has a high loading (70 wt%) of active material (S), a high tap density of ∼0.92 g cm-3, and a reversible capacity of ∼505 mAh g-1 (∼464 mAh cm -3) at a current density of 1680 mA g-1 (1C). When coated with a thin layer of cation exchange Nafion film, the migration of dissolved polysulfide anions from the FGSS nanocomposite was effectively reduced, leading to a good cycling stability of 75% capacity retention over 100 cycles. This sandwich-structured composite conceptually provides a new strategy for designing electrodes in energy storage applications.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry