| Aqueous zinc ion batteries（ZIBs）have attracted much attention for their safety,abundant zinc reserves and low cost.However,the application of ZIBs is severely constrained by unsatisfactory capacity or poor circulation life due to the large radius of hydrated Zn2+,slow diffusion kinetics within the main material,collapse of cathode material,and the easy growth of Zn negative dendritic crystals.Therefore,in order to expand the application range and improve the performance of ZIBs,the development of cathode materials with long cycle life and high discharge capacity is a pressing problem to be solved.Taking Mo S2as the object of investigation,this article focuses on the compound modification of Mo S2 as well as the electrochemical properties of zinc storage using interlayer engineering techniques,phase engineering and conducting polymer composites,targeting the issues of small layer spacing of Mo S2,large inert substrate,poor electrical conductivity and severe agglomeration.The details of the study are as follows:（1）Glucose was used as an inducer,and at the right temperature,the glucose became a thin carbon layer,which was coated during the self-assembly of Mo S2 to prepare Gluc-Mo S2with 1T phase.Meanwhile,thin carbon layers covering the Mo S2 layer can extend the gap between the Gluc-Mo S2 layers to 0.75 nm,reducing the resistance of zinc ions to the sandwich layer.The results showed that Gluc-Mo S2 has reached a reversible capacity of 120 m Ah g-1 at0.5 A g-1,which is six times higher than that of bulk Mo S2.It also has an initial capacity of96m Ah g-1 at a rate of 1A g-1 and a reversible capacity of 65 m Ah g-1 after 300 cycles of operation.（2）Structural unsteadiness and sluggish diffusion of divalent zinc cations in cathodes during cycling severely limit further applications of Mo S2 for rechargeable aqueous zinc-ion batteries（ZIBs）.To circumvent these hurdles,herein,phosphorus（P）atom embedded three-dimensional marigold-shaped 1T Mo S2 structures combined with the design of S vacancies（Sv）are synthesized via the oxygen-assisted solvent heat method.The oxygen-assisted method is utilized to aid the P-embedding into the Mo S2 crystal,which can expand the interlayer spacing of P-Mo S2 and strengthen Zn2+intercalation/deintercalation.Meanwhile,the three-dimensional marigold-shaped structure with 1T phase retains the internal free space,can adapt to the volume change during charge and discharge.Moreover,Sv is not only conducive to the formation of rich active sites to diffuse electrons and Zn2+.The electrochemical results show that the capacity remains at 102 m Ah g-1 after 3260 cycles at a current of 0.5 A g-1,showing excellent electrochemical performance for Zn2+storage.This research provides a more efficient method of P atom embedded Mo S2-based electrodes and will heighten our comprehension of developing cathodes for the ZIBs.（3）Graphene（GO）is highly sought after because of its good electrical conductivity and mechanical properties,which can be used as a three-dimensional skeleton of various materials.Here,we designed self-supporting 3D structural surfaces of perforated graphene（HG）skeletons grown in situ during self-assembly of Mo S2 nanoparticles,and synthesized composite structural materials of Mo S2 and reductive graphene（RGO）.By etching GO in H2O2 environment,RGO will continue to aggregate to form a three-dimensional conductive network under the action of van der Waals force.Moreover,the Mo S2 nanosheets are confined on the surface of RGO and alternate with the layered structure of RGO,which reduces the stacking and agglomeration of the composites.The RGO/Mo S2 nanoparticles had a good discharge ratio of 204 m Ah g-1 at current density of 0.1 A g-1.This strategy provides new insights into the construction of anodes for ZIBs based on a combination of Mo S2 and carbon-based materials. |
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