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To overcome obstacles hindering the commercialization of lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs), we introduce a cost-effective single-step sulfurization strategy for synthesizing iron sulfide (Fe 0.975 S) nanohybrids, augmented by N,S codoped carbon. The resulting N,S codoped carbon-coated Fe 0.975 S (Fe 0.975 S@NSC) electrode exhibits exceptional potential as a highly reversible anode material for both LIBs and SIBs. With impressive initial discharge and charge capacities (1658.2 and 1254.9 mAh g -1 for LIBs and 1450.9 and 1077.1 mAh g -1 for SIBs), the electrode maintains substantial capacity retention (900 mA h g -1 after 1000 cycles for LIBs and 492.5 mA h g -1 after 600 cycles for SIBs at 1.0 A g -1 ). The LiMn 2 O 4 //Fe 0.975 S@NSC and Na 3 V 2 (PO 4 ) 3 //Fe 0.975 S@NSC full batteries can maintain excellent reversible capacity and robust cycling stability. Ex situ and in situ X-ray diffraction, density functional theory (DFT) calculations, and kinetics analysis confirm the promising energy storage potential of the Fe 0.975 S@NSC composite.

The practical application of Molybdenum sulphide (MoS 2 ) electrodes has been hindered by its structural instability, and poor electrical conductivity. To enhance the cycle stability and rate performance of MoS 2 in lithium/sodium-ion batteries (LIBs/SIBs), we synthesized a graphene-supported MoS 2 composite (MoS 2 @rGO) with affluent covalent bridged bonds through a facile and scalable hydrothermal and annealing process. The covalent bridged bonds of Mo-S-C, Mo-O-C and C-O-S provide an effective charge transfer path between MoS 2 and graphene, facilitating fast charge hopping and improving rate performance. As anode materials for LIBs, the MoS 2 @rGO exhibited exceptional long-term cycle life (906 mAh g -1 at 1.0 A g -1 after 400 cycles) and outstanding rate capability (1267.7/314.7 mAh g -1 at 0.1/6.5 A g -1 ). Additionally, the MoS 2 @rGO electrode demonstrated a stable reversible capacity of 521.7 mAh g -1 at 1.0 A g -1 after 700 cycles and excellent rate capabilities of 665.1 and 326.3 mAh g -1 at 0.1 and 10.0 A g -1 in SIBs. The edge Mo of MoS 2 is directly coupled with the oxygen of the functional group on rGO, achieved by adjusting the pH value of the solution to tune the surface charge feature, can effectively enhance the structural stability of electrode even under higher current density., (© 2023 IOP Publishing Ltd.)