CNTs@S cathode modified with a barrier layer of TiO 2 -decorated reduced graphene oxide for lithium–sulfur batteries

In this work, reduced graphene oxide decorated with well-distributed TiO2 nanoparticles is fabricated through one-step hydrothermal reaction to modify CNTs@S cathode as a barrier layer. Its three-dimensional interconnected layered structure can restrain the migration of polysulfides, as well as promote electrical and ionic conduction. The uniformly distributed TiO2 nanoparticles on reduced graphene oxide surface also anchor the lithium polysulfides through chemical interaction, which benefits the cycle stability of the sulfur-containing cathode. As a result, the sulfur-containing cathode with the barrier layer reaches an initial reversible specific capacity of 1090.4 mAh g−1 at 0.2C, with the capacity retention of 93.1% after 150 cycles and the coulombic efficiency above 99%.