Hierarchically Porous C/Fe₃C Membranes with Fast Ion-Transporting Channels and Polysulfide-Trapping Networks for High-Areal-Capacity Li–S Batteries

We report here highly scalable yet stackable C/Fe 3 C membranes with fast ion-transport micro-/nanochannels and polysulfide-trapping networks via a facile phase-inversion process for high-areal-capacity Li–S batteries. The membrane cathodes with aligned channels and hierarchically porous networks significantly promote Li + and electron transportation and meanwhile trap soluble polysulfide intermediates (LiPSs) effectively via strong chemical adsorption of the doped Fe 3 C nanoparticles in the membrane toward LiPSs. We further demonstrated that five-layer membrane electrodes with high S loading of 7.1 mg cm –2 were readily prepared via layer-by-layer stacking of the C/Fe 3 C membrane, which can deliver a high capacity of 726 mA h g –1 after 100 cycles, corresponding to an ultra-high-areal-capacity of 5.15 mA h cm –2 at a low electrolyte/sulfur ( E / S ) ratio of 6.4 μL mg –1 . The scalable multifunctional membrane electrodes with excellent electrochemical performance under high-sulfur-loading and lean electrolyte conditions reveal its promising applications in practical Li–S batteries.