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Despite the abundant reserves and high theoretical capacity of Na–S batteries, it is still limited by the sluggish reaction kinetics of polysulfides during ultrafast charging and discharging to provide stable and high sodium-ion storage performance. Herein, a catalytic strategy is proposed to change the direction of the Coulomb interaction of S–S bonds to achieve high rate reaction kinetics in polysulfides. In this strategy, a NaxVS2 structure is constructed in VS2/S nanocomposite electrodes to support S for superior performance (784 mA h/g at 0.1 A/g and 512 mA h/g at 10 A/g) during sodium storage process. The electrode can still exhibit stable cycling performance at a very high current density (5000 cycles at 20 A/g). The Na-inserted VS2 (NaxVS2) changes the charge distribution of S in polysulfide molecules, altering the Coulomb interaction between S atoms in polysulfide to form repulsion-induced breaking of S–S bond. This altering effect on the atomic Coulomb interaction is essential to promoting the conversion reaction of polysulfides. The above strategy of changing the Coulomb interaction between S atoms not only provides a reference for the design of nanostructures for electrochemical processes with multistep reactions but also inspires angles and ideas for realizing high-performance Na–S batteries. [ABSTRACT FROM AUTHOR]

Iron carbodiimide (FeNCN) often suffers from unstable interfacial structure with an unexpected failure of Na-ion storage performance. In this work, Co 3 O 4 particles were deposited on the surface of FeNCN. This Co 3 O 4 nanolayer led to the formation of a Na 2 CO 3 -rich inorganic component SEI film to enhance the stability of a promoted-loading FeNCN electrode interface with fast Na + migration pathway. Benefitting from this strategy, the FeNCN electrode could present a capacity retention rate of 99.95% per cycle after 1500 cycles at 1 A g -1 . The design of interfacial structure in a promoted-loading electrode could be a reference for stable and high-rate performance of carbodiimide-based materials.