Although lithium–sulfur batteries have high theoretical energy density of 2600 Wh kg−1, the sluggish redox kinetics of soluble liquid polysulfide intermediates during discharge and charge is one of the main reasons for their limited battery performance. Designing highly efficient electrocatalysts with a core–shell like structure for accelerating polysulfide conversion is vital for the development of Li–S batteries. Herein, core–shell MoSe2@C nanorods are proposed to manipulate electrocatalytic polysulfide redox kinetics, thereby improving the Li–S battery performance. The 1D MoSe2@C is synthesized via a facile hydrothermal and subsequent selenization reaction. The electrocatalysis of MoSe2 is confirmed by the analysis of symmetric batteries, Tafel curves, changes of activation energy, and lithium‐ion diffusion. Density functional theory calculations also prove the low Gibbs free energy of the reaction pathway and the lithium‐ion diffusion barrier. Therefore, the Li–S batteries using MoSe2 electrocatalyst exhibit an excellent rate performance of 560 mAh g−1 at 1 C with a high sulfur loading of 3.4 mg cm−2 and an areal capacity of 4.7 mAh cm−2 at a high sulfur loading of 4.7 mg cm−2 under lean electrolyte conditions. This work provides a deeper insight into regulation of polysulfide redox kinetics in electrocatalysts for Li–S batteries.

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Porous Co-NbN spheres with excellent conductivity are used as sulfur hosts for lithium-sulfur batteries, which deliver excellent long-term cycle stability and performance with a high sulfur loading and lean electrolyte.

Nanostructured anode materials have attracted significant attention for lithium-ion batteries (LIBs) due to their high specific capacity. However, their practical application is hindered by the rather low areal capacity in the ultrathin electrode (∼1 mg cm −2 ). Herein, we propose a new strategy of an all-conductive electrode to fabricate a flexible and free-standing vanadium nitride@N-doped carbon/graphene (VN@C/G) thick electrode. Due to the free-standing structure and absence of any nonconductive components in the electrode, the obtained thick electrode displays excellent cycling performances. With the high mass loading of 5 mg cm −2 , VN based electrodes achieve a reversible capacity of 2.6 mAh cm −2 after 200 cycles. Moreover, the all-conductive electrode allows an ultrahigh areal capacity of 7 mAh cm −2 with a high mass loading of 18.3 mg cm −2 , which is comparable to state-of-the-art graphite anodes (4 mAh cm −2 ). Theoretical calculations prove the metallic conductivity of VN, which allows fast charge transport in the thick electrode. This strategy of fabricating all-conductive electrodes shows great potentials to achieve high areal capacity in practical lithium-ion batteries.

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