The sluggish kinetics and four electron oxidation process of oxygen evolution reaction (OER) limit the application of water splitting. Recently, NiFe-layered double hydroxides (NiFe LDHs) have shown great potential to...

The biggest obstacles of putting lithium−sulfur batteries into practice are the sluggish redox kinetics of polysulfides and serious "shuttle effect" under high sulfur mass loading and lean-electrolyte conditions. Herein, Fe 3 C/Fe 3 N@nitrogen-doped carbon nanotubes (NCNTs) as multifunctional sulfur hosts are designed to realize high-areal-capacity Li−S batteries. The Fe 3 N and Fe 3 C particles attached to NCNT can promote the conversion of polysulfides. Besides, NCNT can not only enhance the chemisorption of polysulfides but also increase the special surface area and electrical conductivity by constructing a three-dimensional skeleton network. Integrating the merits of high electrical conductivity, high catalytic activity, and strong chemical binding interaction with lithium polysulfides (LiPSs) to achieve in situ anchoring conversion, the Fe 3 C/Fe 3 N@NCNT multifunctional hosts realize high sulfur mass loading and accelerate redox kinetics. The novel Fe 3 C/Fe 3 N@NCNT/S composite cathode exhibits steady cycle ability and a high areal capacity of 9.10 mAh cm −2 with a sulfur loading of 13.12 mg cm −2 at 2.20 mA cm −2 after 50 cycles.

A lithium–sulfur (Li–S) battery has become a promising energy storage device because of its remarkable excellent specific capacity density and energy density. However, low sulfur utilization and sharp decay of Coulombic efficiency caused by the “shuttle effect” are still gaps that cannot be filled in the long-term development of Li–S batteries. To break through these bottlenecks, we report a ferromagnetic one-dimensional porous Fe3O4@C (1D-Fe3O4@C) electrode as a sulfur host. Benefitting from its one-dimensional (1D) structure, coated carbon shell, and excellent magnetic properties, the as-prepared electrode, besides enhanced conductivity, has a strong binding effect on polysulfides through the Lorentz force and physical adsorption, thereby reducing the “shuttle effect”. At the same time, the porous morphology is conducive to sulfur loading and accommodates the huge volume changes during cycling. The 1D-Fe3O4@C/S electrode shows excellent specific capacity and superior high-rate cyclability, which is demonstrated by capacity retention rates of 95.1 and 92.7% for 200 cycles at 1 and 2 C, respectively.

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