Ni₃FeN functionalized carbon nanofibers boosting polysulfide conversion for Li-S chemistry

Limiting the shuttle effect of polysulfides is an important means to realizing high energy density lithium-sulfur batteries (Li-S). In this study, an efficient electrocatalyst (CNFs@Ni₃FeN) is synthesized by anchoring Ni₃FeN in the carbon nanofibers (CNFs). The CNFs@Ni₃FeN shows electrocatalytic activity and enhances the conversion of polysulfides. After assembling a battery, a high initial capacity (1452 mA h g^-1) and favorable long-time cycling stability (100 cycles) with a capacity retention rate of 83% are obtained by the electrocatalysis of Ni₃FeN. Compared with unmodified CNFs, the cycling stability of CNFs@Ni₃FeN can be greatly improved. The catalytic mechanism is further deduced by X-ray photoelectron spectroscopy (XPS). Our work will inspire the rational design of CNFs@support hybrids for various electrocatalysis applications.