The Preparation Of Copper-based MOF And Their Derivatives And Their Application In Lithium Ion Batteries

With the rapid development of new energy vehicles,large-scale energy storage and smart grid,the increasingly serious global energy crisis has been an urgent challenge for researchers to explore.Researchers are committed to the study of efficient energy conversion devices.Due to the advantages of high theoretical specific capacity and low potential,lithium-ion battery has always been one of the research hotspots in the field of energy storage.MOF-based composites have attracted wide attention in many fields because of their good morphology and porosity because of their transition metal centre,controllable synthesis and pore surface area.However,the poor conductivity of pure MOF limits its application in the field of electrochemistry,and its derivatives have further become popular electrode materials.In this paper,classical Cu-MOF,[Cu3(BTC)2]n was used as the precursor.A series of copper-based MOF composites were prepared by different modifications and derivative ideas and used as anode materials in lithium-ion batteries.The experimental results show that a series of samples can be prepared in batches.Herein,this paper proves the feasibility of the design route and the practical application possibility by studying the relationship between different materials and properties.Furthermore,it provides an idea for us to explore new MOF composites.The main contents and results of this paper are as follows:1.The application of amorphous quasi-Cu-MOF composites derived from Cu-MOF as anode materials for lithium-ion batteries.3D Cu-MOF were prepared by a solvothermal method using Cu(NO3)2·3H2O as the metal source,1,3,5-trimesic acid as the ligand,and lauric acid as the modifier.Quasi-Cu-MOF composites were obtained by calcining Cu-MOF.The results show that the quasi-Cu-MOF composite as an anode for LIBs exhibits a decent reversible specific capacity(627.5 mAh·g-1 at 100 mA·g-1 after 100 cycles)and impressive cycling stability.In the quasi-Cu-MOF composites,the quasi-Cu-MOF part plays an important role in morphology preservation.The porous structure increases the distribution of active centres and promotes the diffusion of the electrolyte.The unique components of derived carbon and copper improve the structure stability and enhance the conductivity.This work is helpful to the design of high-performance electrodes with advanced three-dimensional layered structures.2.Preparation of bimetallic CuCo-MOF derived from Cu-MOF and its application in lithium-ion battery anode material.Through the solvothermal method in 1,using Cu(NO3)2·3H2O and Co(NO3)2·6H2O as metal sources,1,3,5-trimesic acid as the ligand,and PVP as surfactant,a series of bimetallic CuCo-MOF octahedra with different ratios were prepared.The synergistic effect between different ions modulates the diameter of the pores and enhance charge transfer interaction.The existence of cross-linking of bimetallic MOF greatly improves its application potential as electrode materials.This special physicochemical feature enables the bimetallic CuCo-MOF to exhibit good electrochemical performance(519.8 mAh·g-1 at 500 mA·g-1 after 500 cycles)as an anode materia]for lithium-ion batteries.3.The application of Cu@Co-C composites derived from bimetallic CuCo-MOF in anode materials of lithium-ion batteries.Following the experimental idea of 1,the bimetallic CuCoMOF obtained in 2 was calcined in the nitrogen atmosphere at different temperatures,and a series of derivatives were obtained.Under the condition of 300℃,the Cu@Co-C composite has a cavity and copper particles gather inside,which is caused by the existence of polymetallic centres.The precipitation of elemental metal particles makes the structural shrinkage more obvious,but the precipitated elemental metal particles can not contribute to the specific capacity as the electrode material.Finally,the performance of the Cu@Co-C composite material aslithium-ion batteries’ anode material is limited.