A hybrid carbon aerogel with both aligned and interconnected pores as interlayer for high-performance lithium–sulfur batteries

The soluble nature of polysulfide species created on the sulfur electrode has severely hampered the electrochemical performance of lithium–sulfur (Li–S) batteries. Trapping and anchoring polysulfides are promising approaches for overcoming this issue. In this work, a mechanically robust, electrically conductive hybrid carbon aerogel (HCA) with aligned and interconnected pores was created and investigated as an interlayer for Li–S batteries. The hierarchical cross-linked networks constructed by graphene sheets and carbon nanotubes can act as an "internet" to capture the polysulfide, while the microand nano-pores inside the aerogel can facilitate quick penetration of the electrolyte and rapid transport of lithium ions. As advantages of the unique structure and excellent accommodation of the volume change of the active materials, a high specific capacity of 1, 309 mAh·g^-1 at 0.2 C was achieved for the assembled Li–S battery, coupled with good rate performance and long-term cycling stability (78% capacity retention after 600 cycles at 4 C).