Lithium sulfur batteries (LSBs) are regarded as one of the most promising energy storage devices due to the high theoretical capacity and energy density. However, the shuttling lithium polysulfides (LiPSs) from the cathode and the growing lithium dendrites on the anode limit the practical application of LSBs. To overcome these challenges, a novel three-dimensional (3D) honeycombed architecture consisting of a local interconnected Co3O4 successfully assembled into a scalable modified layer through mutual support, which is coated on commercial separators for high-performance LSBs. On the basis of the 3D honeycombed architecture, the modified separators not only suppress effectively the “shuttle effects” but also allow for fast lithium-ions transportation. Moreover, the theoretical calculations results exhibit that the collaboration of the exposed (111) and (220) crystal planes of Co3O4 is able to effectively anchor LiPSs. As expected, LSBs with 3D honeycombed Co3O4 modified separators present a reversible specific capacity with 1007 mAh g–1 over 100 cycles at 0.1 C. More importantly, a high reversible capacity of 808 mAh g–1 over 300 cycles even at 1 C is also acquired with the modified separators. Therefore, this proposed strategy of 3D honeycombed architecture Co3O4 modified separators will give a new route to rationally devise durable and efficient LSBs.

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To solve the shuttle effect of soluble lithium polysulfides (LiPSs), a porous N-doped carbon-supported copper−iridium alloy catalyst composite (CuIr/NC) has been synthesized and served as a modified cathode sulfur host for lithium−sulfur batteries (LSBs). The metal−organic framework-derived calcined carbon frameworks build efficient conductive channels for fast ion/electron transport. Furthermore, alloying noble metals Ir with thiophilic metal Cu provides abundant active sites to effectively capture LiPSs and accelerate the catalytic conversion process, originating from modulating the surface electronic structure of the metal Cu by introducing Ir atoms to affect the 3d-orbital distribution. All of the above are strongly supported by a range of characterization studies and density functional theory calculations. Benefiting from the above advantages, the LSBs generally show satisfactory cycling performance. Apart from exhibiting a terrific initial specific capacity of 1288 mA h g −1 at 0.2 C, they can also keep long-term cycling stability under a high current density up to 5 C together with a slow specific capacity decay ratio (0.033%) per cycle after 1000 cycles. In addition, it is worth mentioning that a high areal capacity (4.7 mA h cm −2 ) with a low E/S ratio (6.2 μL mg −1 ) could still be accomplished at higher sulfur loading (4.3 mg cm −2 ).