Metal sulfides have shown great promise for sodium‐ion batteries due to their excellent redox reversibility and relatively high capacity. However, metal sulfides generally suffer from sluggish charge transport and serious volume change during the charge–discharge process. Herein, potato chip‐like nitrogen‐doped carbon‐coated ZnS/Sb2S3 heterojunction (ZnS/Sb2S3@NC) is precisely synthesized through a sulfurization reaction, and a subsequent metal cation exchange process between Zn2+ and Sb3+. The theoretical calculations and experimental studies reveal the boosted charge transfer in ZnS/Sb2S3@NC composites. Therefore, the ZnS/Sb2S3@NC electrode exhibits excellent cycling stability (a high reversible capacity of 511.4 mAh g‐1 after 450 cycles) and superior rate performance (400.4 mAh g‐1 at 10 A g‐1). In addition, ZnS/Sb2S3@NC is based on a conversion‐alloy reaction mechanism to store Na+, which is disclosed by the X‐ray diffraction and high resolution transmission electron microscopy analysis. This effective synthesis method can provide a reference for the design of other high‐performance electrode materials for sodium‐ion batteries.

To date, the fabrication of advanced anode materials that can accommodate both Na+ and K+ storage is still very challenging. Herein, we developed a facile solvothermal and subsequent annealing process to synthesize SnS2/RGO composite, in which SnS2 nanosheets are bonded on RGO, and investigated their potential as anodes for Na+ and K+ storage. When used as an anode in SIBs, the as-prepared SnS2/RGO displays preeminent performance (581 mAh g−1 at 0.5 A g−1 after 80 cycles), which is a significant improvement compared with pure SnS2. More encouragingly, SnS2/RGO also exhibits good cycling stability (130 mAh g−1 at 0.3 A g−1 after 300 cycles) and excellent rate capability (520.8 mAh g−1 at 0.05 A g−1 and 281.4 mAh g−1 at 0.5 A g−1) when used as anode for PIBs. The well-engineered structure not only guarantees the fast electrode reaction kinetics, but also ensures superior pseudocapacitance contribution during repeated cycles, which has been proved by kinetic analysis.

Conversion-type CoP is a promising anode candidate for sodium-ion batteries (SIBs) thanks to their abundant resources and high theoretical capacity. However, the low reversible capacity and inferior cycle life are two major obstacles that limit its practical application in SIBs. Herein, cobalt-based metalorganic framework derived CoP nanoparticles coupled with reduced graphene oxide (RGO) composite (CoP/RGO) has been successfully prepared. The optimized CoP/RGO presents a high reversible capacity (258.6 mAh g À 1 at 0.1 A g À 1 ), superior rate capability (173 mAh g À 1 at 2 A g À 1 ) and extraordinary durability (155 mAh g À 1 at 0.5 A g À 1 after 500 cycles with the per cycle capacity decay rate of only 0.065 %). In addition, electrochemical analyses reveal fast reaction kinetics and high surface capacitive contribution in CoP/RGO composite, which can be responsible for the excellent performance. Furthermore, the CoP/RGO//Na 3 V 2 (PO 4 ) 3 sodium-ion full cells are assembled successfully and display an initial charge capacity of 231.1 mAh g À 1 at 0.1 A g À 1 . Considering the low cost and great electrochemical performances, this work may provide some new opportunities for the synthesis of activity anode materials for SIBs.

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