3-D Edge-Oriented Electrocatalytic NiCo ₂ S ₄ Nanoflakes on Vertical Graphene for Li-S Batteries

Polysulfide shuttle effect, causing extremely low Coulombic efficiency and cycling stability, is one of the toughest challenges hindering development practical lithium sulfur batteries (LSBs). Introducing catalytic nanostructures to stabilize otherwise soluble polysulfides promote their conversion solids has been proved be an effective strategy in attacking this problem, but heavy mass catalysts often results a specific energy whole electrode. Herein, by designing synthesizing free-standing edge-oriented NiCo 2 S 4 /vertical graphene functionalized carbon nanofiber (NCS/EOG/CNF) thin film as overlayer incorporated cathode, polysulfide effect largely alleviated, revealed enhanced electrochemical performance measurements function demonstration. Different from other reports, nanosheets synthesized here have 3-D structure with fully exposed edges easily accessible in-plane surfaces, thus providing high density active sites even small mass. The EOG/CNF scaffold further renders conductivity structure. Combined, novel structure, loading fraction, leads high-performance cathodes toward LSB technology.