Double-Shelled NiO-NiCo2O4 Heterostructure@Carbon Hollow Nanocages as an Efficient Sulfur Host for Advanced Lithium-Sulfur Batteries

Double-shelled NiO-NiCo2O4 heterostructure@carbon hollow nanocages as efficient sulfur hosts are synthesized to overcome the barriers of lithium-sulfur (Li-S) batteries simultaneously. The double-shelled nanocages can prevent the diffusion of lithium polysulfides (LiPSs) effectively. NiO-NiCo2O4 heterostructure is able to promote polysulfide conversion reactions. Furthermore, the thin carbon layer outside can improve the electrical conductivity during cycling. Besides, such unique double-shelled hollow nanocage architecture can also accommodate the volumetric effect of sulfur upon cycling. As a result, the prepared S/NiO-NiCo2O4@carbon (C) electrode exhibits good rate capacities and stable cycling life up to 500 cycles at 0.5 C with a very low capacity decay rate of only approximate to 0.059% per cycle.