Research Of Novel Ion Batteries Based On Transition Metal Dichalcogenides

With the development of industrialization and the improvement of people’s living standards,as well as the depletion of fossil energy such as coal and oil,green and sustainable clean energy needs to be developed and utilized.In this context,rechargeable batteries for energy conversion and storage have attracted a lot of attention in today’s world.In the past few decades,great efforts have been devoted to the preparation and development of transition metal dichalcogenides materials for alkali metal ion batteries.However,their electrochemical performance is still severely affected by structural aggregation and fragmentation during the conversion reaction.In this paper,molybdenum disulfide and molybdenum diselenide in transition metal dichalcogenides are mainly used in bromide-ion batteries and sodium-zinc dual-ion batteries,respectively,and their electrode materials,electrolytes and working principles are studied respectively.We study the application of molybdenum disulfide in bromine ion batteries.In this study,we achieved a bromine-ion battery with high specific capacity（151 m Ah/g）and excellent stability（over 5000 cycles）using Mo S₂ nanoflowers with excellent Br^-storage properties as the cathode active material.Through a series of characterization analyses,it is proved that bromine ions are embedded in Mo S₂ during the charging process.During discharge,Br^-is extracted from Mo S₂ and moves to the negative electrode.This reversible and stable chemistry provides feasibility for intercalation/deintercalation of bromine-ion batteries.Our proposed novel bromine ion battery still exhibits good electrochemical performance under non-room temperature conditions.A new non-toxic and green bromine-ion battery is expected to become a strong competitor to lithium-ion batteries.We explore the application of molybdenum diselenide in sodium-zinc dual-ion batteries.Hybrid dual-ion batteries have attracted much attention due to their low cost,high operating voltage,and environmental friendliness.In this work,we propose an aqueous Na-Zn dual-ion battery based on Mo Se₂ nanospheres,and realize the fast charging of the aqueous hybrid dual-ion battery.This novel hybrid dual-ion battery exhibits a high specific capacity of 134m Ah/g and excellent cycling stability（over 1000 cycles）at 2C rate.In addition,the battery can store 84%of the battery capacity after 5 minutes of charging,which shows its potential in fast-charging energy storage applications.Using two-dimensional Mo Se₂ as the electrode material for hybrid dual-ion batteries,this study provides new ideas for other scholars in dual-ion battery research,and has important research significance.