Constructing Patch‐Ni‐Shelled Pt@Ni Nanoparticles within Confined Nanoreactors for Catalytic Oxidation of Insoluble Polysulfides in Li‐S Batteries

Reducing the deposit of discharge products and suppressing the polysulfide shuttle are critical to enhancing reaction kinetics in Li‐S batteries. Herein, a Pt@Ni core–shell bimetallic catalyst with a patch‐like or complete Ni shell based on a confined catalysis reaction in porous carbon spheres is reported. The Pt nanodots can effectively direct and catalyze in situ reduction of Ni 2+ ions to form core–shell catalysts with a seamless interface that facilitates the charge transfer between the two metals. Thus, the bimetallic catalysts offer a synergic effect on catalyzing reactions, which shows dual functions for catalytic oxidation of insoluble polysulfides to soluble polysulfides by effectively reducing the energy barrier with simultaneous strong adsorption, ensuring a high reversible capacity and cycling stability. A novel process based on the Pt@Ni core–shell bimetallic catalyst with a patch‐like Ni shell is proposed: electronic migration from Ni to Pt forces Ni to activate Li 2 S 2 /Li 2 S molecules by promoting the transformation of Li‐S‐Li to Ni‐S‐Li, consequently releasing Li + and free electrons, simultaneously enhancing protonic/electronic conductivity. The presence of the intermediate state Ni‐S‐Li is more active to oxidize Li 2 S to polysulfides. The Li 2 S bound to adjacent Pt sites reacts with abundant ‐S‐Li species and then releases the Pt sites for the next round of reactions.