Sulfur-embedded porous carbon nanofiber composites for high stability lithium-sulfur batteries

The porous carbon nanofibers-sulfur (PCNFs-S) composite electrode with micro-mesoporous (<10 nm) and meso-macroporous (>10 nm) is successfully designed and prepared via the electro-blown spinning technique and thermal treatment. The meso-macroporous structure in the PCNFs-S composite can provide high sulfur content up to 80 wt%, while micro-mesoporous affords efficient trapping of polysulfides and inhibits the “shuttle effect”. And the tailored porous fibrous network structure and carbon nanotubes (CNTs) in the composite facilitate the construction of a high electrical conductive pathway. Therefore, the lithium-sulfur (Li-S) batteries electrode exhibits high initial discharge capacities as high as 954 and 602.2 mAh g−1 at 0.5 C and 2 C, respectively, and can obtain quite stable capacities of 795 and 601.5 mAh g−1 after 350 cycles.