Amorphous Al2O3 with N-Doped Porous Carbon as Efficient Polysulfide Barrier in Li-S Batteries

Inhibiting the shuttle effect of polysulfides is one key factor to develop a practically applicable Li-S battery. To overcome the shuttle effect, we developed here an ultrastable Li-S battery with amorphous Al2O3 nanohybrid separator for the first time. Through molecular design of the ligands, the material of the separator from carbonized MOF-Al at elevated temperature is composed of amorphous Al2O3 and N-doped porous carbon, which shows higher electrical conductivity, faster lithium diffusion and charge transfer capability, and stronger interaction with lithium polysulfides through the synergistic effect (MOF, metal-organic framework). The fabricated Li-S battery proposed here corresponds to the lowest capacity decay (only 0.054% of capacity decay in each cycle) as far as we know, which may open up new avenues for developing the next-generation lithium-ion battery.