| Molybdenum selenide is one of the hot topics in battery materials due to its small electronegativity,large atom size,and graphite-like structure.these factors facilitate the transmission of ions,which promotes the redox reaction in battery systems.Recently,lithium-ion batteries have limited their development due to factors such as reserves and costs.Market demand has encouraged new energy storage systems to replace lithium-ion batteries in large-scale energy storage.Among them,magnesium batteries and sodium-ion batteries have attracted a lot of attention.Magnesium batteries are still in the development.Although it can bring great advantage that metal magnesium can be used as negative electrode,the system is still not perfect.In the research of sodium-ion batteries,due to the lithium-sodium homogenous effect,the research and development of lithium-ion batteries can be used as reference to sodium-ion batteries,but the size of sodium-ion is too large,the volume expansion during the insertion and extraction process will affect the stability of the battery.The layered nanoflake structure can suppress the volume effect in the active material circulation process to a certain extent,while providing more channels for ion transmission.In this paper,clustered MoSe2 nanosheets were first synthesized by hydrothermal reaction.Through characterization tests and comparative analysis,it is concluded that the hydrothermal reaction time is 20 h,the sintering temperature is set to 600? for 1h,and 800? for 1h.Crystallinity.Using MoSe2 as the electrode material to assemble the sodium-ion half-cell test,at a current density of 100 mA/g,the reversible capacity of MoSe2 in the first week was 610 mAh/g,the capacity was not lost after 35 weeks of cycling,and it has excellent cycling performance.For magnesium batteries,a large overpotential is associated with the deposition/stripping of magnesium,which affects the normal charge and discharge of the battery.Recent studies have aided the production of solid electrolytes by adding additives to reduce the negative potential of the anode.In this paper,MoSe2 material is selected to construct a three-dimensional framework,and magnesium is electrochemically deposited as a magnesium electrical anode.Electrochemical tests of magnesium deposition proved that there is a magnesiophilic interface at MoSe2,and magnesium is preferentially deposited on the surface of MoSe2.Comparing with the initial electrode,the electrode with magnesium deposition/stripping at a large capacity of 10 mAh/cm2 and the electrode after 1,000 cycles were performed by SEM,respectively,which proved the stability of the three-dimensional magnesiophilic MoSe2 electrode structure.Finally,the overpotential test of the magnesiophilic MoSe2 electrode and Mg electrode at different current densities.The data intuitively shows that the magnesiophilic MoSe2 electrode significantly reduces the negative overpotential of the Mg battery compared to the pure Mg electrode.Pure MoSe2 materials are not suitable for battery charging and discharging at high current densities,and they need to be improved.We have grown MoSe2 in situ on functional carbon cloth(CACC)as the negative electrode of sodium-ion batteries.Surfactants were added during the hydrothermal process and ultrasonic treatment was performed after the hydrothermal process to finally obtain the expected morphology.Various structural tests and analyses proved that MoSe2 grows uniformly on CACC.CACC@MoSe2 was used to assemble sodium-ion half-cells for electrochemical tests.At a current density of 1000 mA/g,the first week reversible capacity of CACC@MoSe2 was 373.8 mAh/g.After 160 weeks,the material can maintain 65.1%capacity.In comparison,the capacity of MoSe2 rapidly decays.Analysis shows that due to the high electron conductance of the CACC@MoSe2 electrode and the stable framework of 3D carbon materials,CACC@MoSe2 has excellent cycle stability and rate performance. |
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