Nitrogen-Doped Porous Nanofiber Aerogel-Encapsulated Staphylo-Ni₃S₂ Accelerating Polysulfide Conversion for Efficient Li–S Batteries

The low conductivity of sulfur substances and the fussy effect of lithium polysulfides (LPS) limit the practical application of lithium–sulfur batteries (LSBs). In this work, Ni 3 S 2 is in situ synthesized on N-doped 3D carbon nanofibers with an optimized pore structure as a cathode material for LSBs. The conductive carbon nanofiber skeleton with a hierarchical (micropore–mesopore–macropore) structure etched by Cd 2+ can reduce the interface resistance of the cathode and remiss volume expansion during charge–discharge progress. The Ni was vulcanized and nitrogen-doped successively during the annealing process. In addition, the polar Ni 3 S 2 and N-doped carbon structure can promote the catalytic conversion of LPS and regulate the 3D nucleation of Li 2 S, which could reduce the reaction energy barrier. Therefore, the NCF-Cd-Ni 3 S 2 -NC cathode can maintain a high initial capacity (1080.2 mAh g –1 ) and excellent stability at 0.1C. This work provides an important basis for the synthesis of high efficiency and inexpensive cathode carrier materials for LSBs.