Controllable Syntheis On Antimony-Based Electrode Materials As Electrodes For Secondary Ion Batteries

Lithium ion battery and sodium ion battery,as the most popular rechargeable batteries,exhibit the advantages of high energy density and long cycle life and so on,facilitating to effectively solve the problems of fossil energy exhaustion and environmental pollution.However,due to the low capacity of anode material,the current commercialized secondary battery fails to be applied in the field of large-scale power storage and meet the growing demand of people's life.Therefore,it is urgent to develop new anode materials with high energy density and high power density.Antimony-based anode materials,as an important kind of anode material,demonstrate high conductivity,suitable electrochemical reaction potential and alloying reaction during the electrochemical energy storage process,thus providing high specific capacity.However,serious volume expansion of Sb-based electrode during the electrochemical cycle process,makes the active material structure destroyed and slow transfer efficiency,finally results in the decreasing electrochemical performance.Therefore,to overcome the issues,the structure of Sb-based electrode materials are designed,including NiSb thin film,Sb/ZnS@C hollow sphere,ZnS-Sb2S3@C core-double shell polyhedron,Sb|P-S@C foam,TiSe2@TiSe2-Sb2Se3 yolk-shell structure.And the energy storage mechanism is explored in depth based on the controllable nano-scale pore engineering,intermetallic alloying engineering and surface interface engineering.(1)A low-cost,facile and high efficient in-situ solvothermal reaction route is for the first time developed to synthesize three-dimensional nickel-antimony(3D NiSb)thin film using 3D Ni foam template,as anode electrode for sodium ion batteries(SIBs).The microstructure design and controllable synthesis have been proved reasonably and efficiently to bring about excellent electrochemical property.A specific capacity of 420 mAh g-1 after 100 cycles at current density of 100 mA g-1 can be achieved.The excellent electrochemical performance could be attributed to the special 3D-binder-free conductive network to connect NiSb nanoparticles and three-dimensional contact area with electrolyte,which is beneficial to the charge transfer kinetics and electrochemical performance.Moreover,the porous structure offers enough space to alleviate the volume changes and the stress generated from the sodiation/desodiation process.Most importantly,3D porous Ni foam,as a supporter for NiSb nanoparticles,can effectively prevent the agglomeration of the NiSb and Na3Sb nanoparticles.(2)Combining the advantage of metal,metal sulfide and carbon,mesoporous hollow Sb/ZnS@C hybrid heterostructures composed of Sb/ZnS inner core and carbon outer shell are rationally designed based on a robust template of ZnS nanosphere,as anodes for high-performance sodium ion batteries(SIBs).A partial cation exchange reaction based on the solubility difference between Sb2S3 and ZnS can transform mesoporous ZnS to Sb2S3/ZnS heterostructure.To get a stable structure,a thin contiguous resorcinol-formaldehyde(RF)layer is introduced on the surface of Sb2S3/ZnS heterostructure.The effectively protective carbon layer from RF can be designed as the reducing agent to convert Sb2S3 to metallic Sb to obtain Sb/ZnS@C hybrid heterostructures.Simultaneously,the carbon outer shell is beneficial to improve the charge transfer kinetics,and can maintain the structure stability during the repeated sodiation/desodiation process.Owing to its unique stable architecture and synergistic effects between the components,the porous Sb/ZnS@C hybrid heterostructure SIBs anode shows us a high reversible capacity,good rate capability and excellent cycling stability by turning the optimized voltage range.(3)Taking advantage of zeoliticimidazolate framework(ZIF-8),ZnS-Sb2S3@C core-double shell polyhedron structure is synthesized through a sulfurization reaction between Zn2+ dissociated from ZIF-8 and S2-from thioacetamide(TAA),and subsequently a metal cation exchange process between Zn2+ and Sb3+,in which carbon layer is introduced from polymeric resorcinol-formaldehyde to prevent the collapse of the polyhedron.The polyhedron composite with a ZnS inner-core and Sb2S3/C double-shell as anode for sodium ion batteries(SIBs)shows us a significantly improved electrochemical performance with stable cycle stability,high Coulombic efficiency and specific capacity.Peculiarly,introducing carbon shell not only acts as an important protective layer to form a rigid construction and accommodate the volume changes,but also improves the electronic conductivity to optimize the stable cycle performance and the excellent rate property.The architecture composed of ZnS inner core and a complex Sb2S3/C shell not only facilitates the facile electrolyte infiltration to reduce the Na-ion diffusion length to improve the electrochemical reaction kinetics,but also prevents the structure pulverization caused by Na-ion insertion/extraction.This approach to prepare metal sulphides based on MOFs can be further extended to design other nanostructured systems for high performance energy storage devices.(4)Phosphosulphide composites began to be used in energy storage field as an emerging category.However,the restricted variety of morphology structure,the large volume expansion and the poor electronic conductivity will lead to the inferior cycling stability.Herein combing with advantages of high electronic conductivity of metallic Sb and high theoretical capacity of phosphorus,non-metallic porous phosphosulfide nanospheres and ultrafine metallic Sb nanoparticles are synergistically anchored on 3D macroporous interconnected carbon foam to form Sb|P-S@C foam anode for high-performance sodium ion batteries(SIBs).The characteristics of porous feature of phosphosulfide nanospheres,high electrical conductivity and ultrafine Sb nanoparticles facilitate the alleviation of volume expansion and improvement of charge transfer and diffusion kinetics.3D macroporous interconnected carbon foam as a framework offers enough active sites for the formation of Sb|P-S particles,not only effectually inhibiting the aggregation of Sb and phosphosulfide nanospheres due to the high surface energy and activity,but also effectively preventing anode material from pulverization and increasing the effective contact area between electrode and electrolyte,serving as 3D channel for electron/ion rapid transfer.Consequently,benefitting from the structural superiorities and synergistic effect,Sb|P-S@C foam anode delivers a specific capacity of 490 mAh g-1 with a remarkable capacity retention after 1000 cycles at 0.1 A g-1.The low-cost strategy for porous Sb|P-S@C foam anode sets up new paths to design long-cycling large-scale energy storage system.(5)The polarization and blocking effect in bulk TiSe2 anode during lithiation/delithiation process leads to the sluggish interfacial charge transfer kinetics and low diffusion coefficient,thus resulting in low specific capacity and severe capacity fading.Herein,Titanium-MIL-125 derived porous TiSe2@TiSe2-Sb2Se3 yolk-shell heterostructure are synthesized by a novel synergetic etching/ion exchanging and situ-selenizing route,as anodes for high performance lithium ion battery(LIB).TiSe2@TiSe2-Sb2Se3 yolk-shell heterostructure can effectively induce local built-in electric field to enhance interfacial charge transfer and redox reaction kinetics,improving van der Waals interlayer utilization efficiency and alleviating polarization and blocking effect.Particularly,both TiSe2 and TiSe2-Sb2Se3 are embedded in porous yolk-shell carbon matrix,exhibiting abundant porosity characteristics and high electronic conductivity,providing more achievable active sites and shorter lithium ion diffusion pathway,facilitating to release volume strain and maintain structure stability.Benefitting from the synergistic effect of porous yolk-shell heterostructure,the polarization and blocking effect are effectively suppressed,yolk-shell TiSe2@TiSe2-Sb2Se3 heterostructure electrode shows remarkable specific capacity,superior rate capability and cycle stability.The lithium storage characteristics and redox reaction mechanism of TiSe2@TiSe2-Sb2Se3 electrodes are deeply investigated.The synthetic route of the yolk-shell TiSe2@TiSe2-Sb2Se3 heterostructure anode can be extended to related nanostructured systems for high performance energy storage device application.