A new LiCoO2 recovery technology for Li-ion batteries was studied in this paper. LiCoO2 was peeled from the Al foil with dimethyl acetamide (DMAC), and then polyvinylidene fluoride (PVDF) and carbon powders in the...A new LiCoO2 recovery technology for Li-ion batteries was studied in this paper. LiCoO2 was peeled from the Al foil with dimethyl acetamide (DMAC), and then polyvinylidene fluoride (PVDF) and carbon powders in the active material were eliminated by high temperature calcining. Subsequently, Li2CO3, LiOH-H20 and LiAc-2H2O were added into the recycled powders to adjust the Li/Co molar ratio to 1.00. The new LiCoO2 was obtained by calcining the mixture at 850℃ for 12 h in air. The structure and morphology of the recycled powders and resulting samples were studied by XRD and SEM techniques, respectively. The layered structure of LiCoO2 synthesized by adding Li2CO3 is the best, and it is found to have the best characteristics as a cathode material in terms of charge-discharge capacity and cycling performance. The first discharge capacity is 160 mAh·g^-1 between 3.0-4.3 V. The discharge capacity after cycling for 50 times is still 145.2 mAh·g^-1.展开更多
Plasma spray-physical vapor deposition(PS-PVD)as a novel process was used to prepare feather-like columnar thermal barrier coatings(TBCs).This special microstructure shows good strain tolerance and non-line-of-sight(N...Plasma spray-physical vapor deposition(PS-PVD)as a novel process was used to prepare feather-like columnar thermal barrier coatings(TBCs).This special microstructure shows good strain tolerance and non-line-of-sight(NLOS)deposition,giving great potential application in aero-engine.However,due to serious service environment of aero-engine,particle erosion performance is a weakness for PS-PVD 7YSZ TBCs.As a solution,an Al-modification approach was proposed in this investigation.Through in-situ reaction of Al and ZrO2,anα-Al2O3 overlay can be formed on the surface of 7YSZ columnar coating.The results demonstrate that this approach can improve particle erosion resistance since hardness improvement of Al-modified TBCs.Meanwhile,as another important performance of thermal cycle,it has a better optimization with 350-cycle water-quenching,compared with the as-sprayed TBCs.展开更多
Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the applicat...Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the application prospects of batteries.However,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application requirements.Therefore,this review proposes several strategies to address these challenges.First,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion doping.Second,homogeneous surface coating and concentration gradient modification are reviewed.In addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are proposed.Finally,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials.展开更多
Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challen...Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction products.In this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(C@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se batteries.Using the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@C@TiN)display superior utilization of the active material and remarkable cycling stability.As a result,Al-Se batteries equipped with the as-prepared Se@C@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 cycles.This improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@C@TiN.展开更多
Activated carbon aerogels(ACAs) derived from sol-gel polycondensation of resorcinol (R) and formaldehyde (F) were pyrolyzed under Ar flow and activated in CO2 atmosphere. The morphology of ACAs was characterized...Activated carbon aerogels(ACAs) derived from sol-gel polycondensation of resorcinol (R) and formaldehyde (F) were pyrolyzed under Ar flow and activated in CO2 atmosphere. The morphology of ACAs was characterized by scanning electron microscopy (SEM) and the structural properties were determined by N2 adsorption at 77 K. The results show that ACAs have a typical three-dimensional nanonetwork structure composing of cross-linking of carbon nanoparticles. The specific surface area and the total pore volume remarkably increase with increasing activation time while the previous porous structure still remains. The specific capacitance of the 950-10-ACA electrode can reach up to 212.3 F/g in 6 mol/L KOH electrolyte. The results of constant-current charge-discharge testing indicate that the ACAs electrodes present fast charge- discharge rate and long cycle life (about 98% capacitance retained after 3000 charge-discharge cycles at 1.25 mA/cm2). Lower internal resistances can be achieved for 950-10-ACA electrode in KOH electrolyte. Our investigations are very important to improve the wettability and electrochemical performance of electrode for supercapacitors.展开更多
Lithium sulfur batteries(LSBs)are recognized as promising devices for developing next-generation energy storage systems.In addition,they are attractive rechargeable battery systems for replacing lithium-ion batteries(...Lithium sulfur batteries(LSBs)are recognized as promising devices for developing next-generation energy storage systems.In addition,they are attractive rechargeable battery systems for replacing lithium-ion batteries(LIBs)for commercial use owing to their higher theoretical energy density and lower cost compared to those of LIBs.However,LSBs are still beset with some persistent issues that prevent them from being used industrially,such as the unavoidable dissolution of lithium polysulfide intermediates during electrochemical reactions and large volume expansion(up to 80%)upon the formation of Li_(2)S,resulting in serious battery life and safety limitations.In the process of solving these problems,it is necessary to maintain a high sulfur content in the cathode materials to ensure that the LSBs have high energy densities and excellent cycle performance.In this review,the novel preparation methods and cathode materials used for preparing LSBs in recent years are reviewed considering the sulfur content and cycle performance.In addition,the problems and difficulties in practically applying cathode materials are described,and the development trend is discussed.展开更多
To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedr...To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)composites.Among them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly distributed.When assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 cycles.It is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.展开更多
To solve the environmental pollution and low yield during the sythesis of zeolitic imidazolate frameworks(ZIFs)and their derived materials,a KOH-assisted aqueous strategy is proposed to synthesize cobalt zeolitic imid...To solve the environmental pollution and low yield during the sythesis of zeolitic imidazolate frameworks(ZIFs)and their derived materials,a KOH-assisted aqueous strategy is proposed to synthesize cobalt zeolitic imidazolate framework(ZIF-67)polyhedrons,which are used as precursors to prepare cobalt selenide/carbon composites with different crystal phases(Co_(0.85)Se,CoSe_2).When evaluated as anode material for lithium ion batteries,Co_(0.85)Se/C composites deliver a reversible capacity of 758.7 m A·h·g^(-1)with a capacity retention rate of 90.5%at 1.0 A·g^(-1)after 500 cycles,and the superior rate capability is 620 m A·h·g^(-1)at 2.0 A·g^(-1).The addition of KOH accelerates the production of ZIF-67 crystals by boosting deprotonation of dimethylimidazole,resulting in rapid growth and structures transition from two-dimensional to three-dimensional of ZIF-67 in aqueous solution,which greatly promotes the application of MOFs in the field of energy storage and conversion.展开更多
The construction of stable cathode electrolyte interphase(CEI)is the key to improve the NCM811 particle structure and interfacial stability via electrolyte engineering.In He’s work,lithium hexamethyldisilazide(LiHMDS...The construction of stable cathode electrolyte interphase(CEI)is the key to improve the NCM811 particle structure and interfacial stability via electrolyte engineering.In He’s work,lithium hexamethyldisilazide(LiHMDS)as the electrolyte additive is proposed to facilitate the generation of stable CEI on NCM811 cathode surface and eliminate H_(2)O and HF in the electrolyte at the same time,which boosts the cycling performance of Li||NCM811 battery up to 1000 or 500 cycles with 4.5 V cut-off voltage at 25 or 60℃.展开更多
Sodium-ion battery is a potential application system for large-scale energy storage due to the advantage of higher nature abundance and lower production cost of sodium-based materials.However,there exist inevitably th...Sodium-ion battery is a potential application system for large-scale energy storage due to the advantage of higher nature abundance and lower production cost of sodium-based materials.However,there exist inevitably the safety problems such as flammability due to the use of the same type of organic liquid electrolyte with lithium-ion battery.Gel polymer electrolytes are being considered as an effective solution to replace conventional organic liquid electrolytes for building safer sodium-ion batteries.In this review paper,the authors present a comprehensive overview of the research progress in electrochemical and physical properties of the gel polymer electrolyte-based sodium batteries.The gel polymer electrolytes based on different polymer hosts namely poly(ethylene oxide),poly(acrylonitrile),poly(methyl methacrylate),poly(vinylidene fluoride),poly(vinylidene fluoride-hexafluoro propylene),and other new polymer networks are summarized.The ionic conductivity,ion transference number,electrochemical window,thermal stability,mechanical property,and interfacial issue with electrodes of gel polymer electrolytes,and the corresponding influence factors are described in detail.Furthermore,the ion transport pathway and ion conduction mechanism are analyzed and discussed.In addition,the advanced gel polymer electrolyte systems including flame-retardant polymer electrolytes,composite gel polymer electrolytes,copolymerization,single-ion conducting polymer electrolytes,etc.with more superior and functional performance are classified and summarized.Finally,the application prospects,development opportunities,remaining challenges,and possible solutions are discussed.展开更多
Due to its high operational voltage and energy density,P2-type Na_(0.67)Ni_(0.3)Mn_(0.7)O_(2) has become a leading cathode material for sodium-ion batteries(SIBs),which is an ideal option for large-scale energy storag...Due to its high operational voltage and energy density,P2-type Na_(0.67)Ni_(0.3)Mn_(0.7)O_(2) has become a leading cathode material for sodium-ion batteries(SIBs),which is an ideal option for large-scale energy storage.However,the practical application of P2-type Na_(0.67)Ni_(0.3)Mn_(0.7)O_(2) is limited by the capacity constraints and unwanted phase transitions,presenting significant challenges to the widespread application of SIBs.To address these challenges and optimize the electrochemical properties of the P2 phase cathode material,this study proposes a Cu and Zn co-doped strategy to improve the electrochemical performance.The incorporation of Cu/Zn can stabilize the P2-phase structure against P2-O2 phase transitions,thus enhancing its electrochemical properties.The as-obtained P2-type Na0.67[Ni_(0.3)Mn_(0.58)Cu_(0.09)Zn_(0.03)]O_(2) cathode material shows an impressive cycling stability,maintaining 80%capacity retention after 1000 cycles at 2 C.The cyclic voltammetry(CV)tests show that the Cu^(2+)/Cu^(3+)redox reaction is also involved in charge compensation during the charge/discharge process.展开更多
Aqueous ammonium ion batteries are regarded as eco-friendly and sustainable energy storage systems.And applicable host for NH_(4)^(+)in aqueous solution is always in the process of development.On the basis of density ...Aqueous ammonium ion batteries are regarded as eco-friendly and sustainable energy storage systems.And applicable host for NH_(4)^(+)in aqueous solution is always in the process of development.On the basis of density functional theory calcula-tions,the excellent performance of NH_(4)^(+)insertion in Prussian blue analogues(PBAs)is proposed,especially for copper hexacyanoferrate(CuHCF).In this work,we prove the outstanding cycling and rate performance of CuHCF via electrochemical analyses,delivering no capacity fading during ultra-long cycles of 3000 times and high capacity retention of 93.6%at 50 C.One of main contributions to superior performance from highly reversible redox reaction and structural change is verified during the ammoniation/de-ammoniation progresses.More importantly,we propose the NH_(4)^(+)diffusion mechanism in CuHCF based on con-tinuous formation and fracture of hydrogen bonds from a joint theoretical and experimental study,which is another essential reason for rapid charge transfer and superior NH_(4)^(+)storage.Lastly,a full cell by coupling CuHCF cathode and polyaniline anode is constructed to explore the practical application of CuHCF.In brief,the outstanding aqueous NH_(4)^(+)storage in cubic PBAs creates a blueprint for fast and sustainable energy storage.展开更多
Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)s...Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.展开更多
Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge.In the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs...Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge.In the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs)with a thickness of 2−4 atomic layers were fabricated via vacuum freeze-drying and nitridation.Then,the h-BNNSs/reduced graphene oxide(rGO)composite were further prepared using a hydrothermal method.Due to the combination of two two-dimensional(2D)van der Waals-bonded materials,the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from−10 to 50℃.When the electrodes worked in a neutral aqueous electrolyte(1 M Na2SO4),they showed a great stable cycling performance with almost 107%reservation of the initial capacitance at 0℃ and 111% at 50℃ for 5000 charge−discharge cycles.展开更多
The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area betw...The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine chain is fatigue wear, and its failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. In addition, the material, hot-treatment method and shaping technique for roller have a great influence upon the resistance to multi-impact. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technique are the effective method to increase its resistance to multi-impact.展开更多
This work focused on the zinc powder coated with Y(OH)3 microparticles by means of ultrasonic immersion for performance improvement of zinc electrodes in alkaline battery systems.Scanning electron microscopy and other...This work focused on the zinc powder coated with Y(OH)3 microparticles by means of ultrasonic immersion for performance improvement of zinc electrodes in alkaline battery systems.Scanning electron microscopy and other characterization techniques were applied to examine the influence of the ultrasonic power on the sonochemical growth of Y(OH)3 microparticles in direct contact with zinc powder.Electrochemical properties of zinc electrodes containing Y(OH)3 microparticles were discussed through the measurement...展开更多
Silicon is being investigated extensively as an anodic material for next-generation lithium ion batteries for portable energy storage and electric vehicles.However,the large changes in volume during cycling lead to th...Silicon is being investigated extensively as an anodic material for next-generation lithium ion batteries for portable energy storage and electric vehicles.However,the large changes in volume during cycling lead to the breakdown of the conductive network in Si anodes and the formation of an unstable solid-electrolyte interface,resulting in capacity fading.Here,we demonstrate nanoparticles with a Si@Mn22.6Si5.4C4@C double-shell structure and the formation of self-organized Si-Mn-C nanocomposite anodes during the lithiation/delithiation process.The anode consists of amorphous Si particles less than 10 nm in diameter and separated by an interconnected conductive/buffer network,which exhibits excellent charge transfer kinetics and charge/discharge performances.A stable specific capacity of 1100 mAh·g-1 at 100 mA·g-1 and a coulombic efficiency of 99.2%after 30 cycles are achieved.Additionally,a rate capacity of 343 mAh·g-1 and a coulombic efficiency of 99.4%at 12000 mA·g-1 are also attainable.Owing to its simplicity and applicability,this strategy for improving electrode performance paves a way for the development of high-performance Si-based anodic materials for lithium ion batteries.展开更多
The lithium–sulfur batteries show the great potential to be the most promising candidate for high energy applications. However, the shuttling of soluble polysulfides deteriorates the battery performance tremendously....The lithium–sulfur batteries show the great potential to be the most promising candidate for high energy applications. However, the shuttling of soluble polysulfides deteriorates the battery performance tremendously. To suppress the diffusion of soluble polysulfides, diatomite that has abundant natural three-dimensional ordered pores is incorporated into the cathode to trap polysulfides. The composite cathode material(S-DM-AB for short), including sulfur(S), diatomite(DM), and acetylene black(AB) is prepared by an impregnation method. For comparison, another composite cathode material(S-AB for short) including sulfur and acetylene black is also prepared by the same method. The battery with S-DMAB composite cathode material delivers a discharge capacity of 531.4 m Ah/g after 300 cycles at 2 C with a capacity retention of 51.6% at room temperature. By contrast, the battery with S-AB composite cathode material delivered a capacity of only 196.9 m Ah/g with a much lower capacity retention of 18.6% under the same condition. The addition of diatomite in the cathode is proved to be a cheap and effective way to improve the life time of the lithium sulfur batteries.展开更多
α-MoO3 nanobelts/carbon nanotubes(CNTs) composites were synthesized by simple hydrothermal method followed by CNTs incorporating, and characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM...α-MoO3 nanobelts/carbon nanotubes(CNTs) composites were synthesized by simple hydrothermal method followed by CNTs incorporating, and characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Cyclic voltammogram(CV), electrochemical impedance spectroscopy(EIS), and galvanostatic charge/discharge testing techniques were employed to evaluate the electrochemical behaviors of α-MoO3 nanobelts/CNTs composites. The results exhibited that compared to bare α-MoO3 nanobelts, the α-MoO3 nanobelts/CNTs composites have better electrochemical performances as cathode materials for lithium ion battery, maintaining a reversible specific capacity of 222.2 mAh/g at 0.3 C after 50 cycles, and 74.1% retention of the first reversible capacity. In addition, the Rct value of the α-MoO3 nanobelts/CNTs is 13 Ω, much lower than 66 Ω of the bare α-MoO3 nanobelts. The better electrochemical performances of the α-MoO3 nanobelts/CNTs composites can be attributed to the effects of the high conductive CNTs network.展开更多
Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anod...Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anodes,a new facile composition and electrode design strategy have been adapted to fabricate a SiO-Sn-Co/graphite(G)anode.It achieves a unique structure where tiny milled SiO-Sn-Co particles are dispersed among two graphite layers.In this hybrid electrode,Sn-Co alloys promoted Li;extraction kinetics,and the holistic reversibility of SiO and graphite enhanced the electrical conductivity.The SiO-Sn-Co/G electrode delivered an average ICE of 77.6%and a reversible capacity of 640 mAh g^(-1)at 800 mA g^(-1),and the capacity retention was above 98%after 100 cycles,which was much higher than that of the SiO with an ICE of 55.3%and a capacity retention of 50%.These results indicated that this was reliable method to improve the reversibility and cycle ability of the SiO anode.Furthermore,based on its easy and feasible fabrication process,it may provide a suitable choice to combine other alloy anodes with the graphite anode.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 50762004 and 50864004)
文摘A new LiCoO2 recovery technology for Li-ion batteries was studied in this paper. LiCoO2 was peeled from the Al foil with dimethyl acetamide (DMAC), and then polyvinylidene fluoride (PVDF) and carbon powders in the active material were eliminated by high temperature calcining. Subsequently, Li2CO3, LiOH-H20 and LiAc-2H2O were added into the recycled powders to adjust the Li/Co molar ratio to 1.00. The new LiCoO2 was obtained by calcining the mixture at 850℃ for 12 h in air. The structure and morphology of the recycled powders and resulting samples were studied by XRD and SEM techniques, respectively. The layered structure of LiCoO2 synthesized by adding Li2CO3 is the best, and it is found to have the best characteristics as a cathode material in terms of charge-discharge capacity and cycling performance. The first discharge capacity is 160 mAh·g^-1 between 3.0-4.3 V. The discharge capacity after cycling for 50 times is still 145.2 mAh·g^-1.
基金We would like to acknowledge the financial support from the National Natural Science Foundation of China(52172067)Guangdong Province Outstanding Youth Foundation(2021B1515020038)+1 种基金Guangdong Special Support Program(2019BT02C629)Guangdong Academy of Sciences Program(2020GDASYL-20200104030).
文摘Plasma spray-physical vapor deposition(PS-PVD)as a novel process was used to prepare feather-like columnar thermal barrier coatings(TBCs).This special microstructure shows good strain tolerance and non-line-of-sight(NLOS)deposition,giving great potential application in aero-engine.However,due to serious service environment of aero-engine,particle erosion performance is a weakness for PS-PVD 7YSZ TBCs.As a solution,an Al-modification approach was proposed in this investigation.Through in-situ reaction of Al and ZrO2,anα-Al2O3 overlay can be formed on the surface of 7YSZ columnar coating.The results demonstrate that this approach can improve particle erosion resistance since hardness improvement of Al-modified TBCs.Meanwhile,as another important performance of thermal cycle,it has a better optimization with 350-cycle water-quenching,compared with the as-sprayed TBCs.
基金the Fundamental Research Funds for the Central Universities,China(No.06500177)the National Natural Science Foundation of China Joint Fund Project(No.U1764255)。
文摘Layered oxide is a promising cathode material for sodium-ion batteries because of its high-capacity,high operating voltage,and simple synthesis.Cycling performance is an important criterion for evaluating the application prospects of batteries.However,facing challenges,including phase transitions,ambient stability,side reactions,and irreversible anionic oxygen activity,the cycling performance of layered oxide cathode materials still cannot meet the application requirements.Therefore,this review proposes several strategies to address these challenges.First,bulk doping is introduced from three aspects:cationic single doping,anionic single doping,and multi-ion doping.Second,homogeneous surface coating and concentration gradient modification are reviewed.In addition,methods such as mixed structure design,particle engineering,high-entropy material construction,and integrated modification are proposed.Finally,a summary and outlook provide a new horizon for developing and modifying layered oxide cathode materials.
基金supported by the National Natural Science Foundation of China(No.52374350)China Postdoctoral Science Foundation(Nos.2020M680347 and 2021T140051)the Fundamental Research Funds for the Central Universities(No.FRF-TP-20-045A1)。
文摘Incorporating a selenium(Se)positive electrode into aluminum(Al)-ion batteries is an effective strategy for improving the overall battery performance.However,the cycling stability of Se positive electrodes has challenges due to the dissolution of intermediate reaction products.In this work,we aim to harness the advantages of Se while reducing its limitations by preparing a core-shell mesoporous carbon hollow sphere with a titanium nitride(C@TiN)host to load 63.9wt%Se as the positive electrode material for Al-Se batteries.Using the physical and chemical confinement offered by the hollow mesoporous carbon and TiN,the obtained core-shell mesoporous carbon hollow spheres coated with Se(Se@C@TiN)display superior utilization of the active material and remarkable cycling stability.As a result,Al-Se batteries equipped with the as-prepared Se@C@TiN composite positive electrodes show an initial discharge specific capacity of 377 mAh·g^(-1)at a current density of 1000 mA·g^(-1)while maintaining a discharge specific capacity of 86.0 mAh·g^(-1)over 200 cycles.This improved cycling performance is ascribed to the high electrical conductivity of the core-shell mesoporous carbon hollow spheres and the unique three-dimensional hierarchical architecture of Se@C@TiN.
基金Funded by the National Science Foundation of China(Nos.11074176 and 10976019)the Research Fund for the Doctoral Program of Higher Education of China(No.20100181110080)
文摘Activated carbon aerogels(ACAs) derived from sol-gel polycondensation of resorcinol (R) and formaldehyde (F) were pyrolyzed under Ar flow and activated in CO2 atmosphere. The morphology of ACAs was characterized by scanning electron microscopy (SEM) and the structural properties were determined by N2 adsorption at 77 K. The results show that ACAs have a typical three-dimensional nanonetwork structure composing of cross-linking of carbon nanoparticles. The specific surface area and the total pore volume remarkably increase with increasing activation time while the previous porous structure still remains. The specific capacitance of the 950-10-ACA electrode can reach up to 212.3 F/g in 6 mol/L KOH electrolyte. The results of constant-current charge-discharge testing indicate that the ACAs electrodes present fast charge- discharge rate and long cycle life (about 98% capacitance retained after 3000 charge-discharge cycles at 1.25 mA/cm2). Lower internal resistances can be achieved for 950-10-ACA electrode in KOH electrolyte. Our investigations are very important to improve the wettability and electrochemical performance of electrode for supercapacitors.
基金the National Natural Science Foundation of China(52103093)the Young Elite Scientists Sponsorship Program by China Association for Science and Technology(2021QNRC001)+2 种基金the Jiangxi Provincial Natural Science Foundation(20212BAB214048)Science and Technology Support Project of Shangrao(2020L009,2021J006)Science and Technological Project of Education Department of Jiangxi(GJJ211704)for funding their contributions to this paper。
文摘Lithium sulfur batteries(LSBs)are recognized as promising devices for developing next-generation energy storage systems.In addition,they are attractive rechargeable battery systems for replacing lithium-ion batteries(LIBs)for commercial use owing to their higher theoretical energy density and lower cost compared to those of LIBs.However,LSBs are still beset with some persistent issues that prevent them from being used industrially,such as the unavoidable dissolution of lithium polysulfide intermediates during electrochemical reactions and large volume expansion(up to 80%)upon the formation of Li_(2)S,resulting in serious battery life and safety limitations.In the process of solving these problems,it is necessary to maintain a high sulfur content in the cathode materials to ensure that the LSBs have high energy densities and excellent cycle performance.In this review,the novel preparation methods and cathode materials used for preparing LSBs in recent years are reviewed considering the sulfur content and cycle performance.In addition,the problems and difficulties in practically applying cathode materials are described,and the development trend is discussed.
基金financially supported by the National Natural Science Foundation of China(No.52102100)the Natural Science Foundation of Jiangsu Province(No.BK20181469)the Guangdong Basic and Applied Basic Research Foundation,China(No.2020A1515110035)。
文摘To solve low efficiency,environmental pollution,and toxicity for synthesizing zeolitic imidazolate frameworks(ZIFs)in organic solvents,a KOH-assisted aqueous strategy is proposed to synthesize bimetallic ZIFs polyhedrons,which are used as precursors to prepare bimetallic selenide and N-doped carbon(NC)composites.Among them,Fe–Co–Se/NC retains the three-dimensional(3D)polyhedrons with mesoporous structure,and Fe–Co–Se nanoparticles are uniform in size and evenly distributed.When assessed as anode material for lithium-ion batteries,Fe–Co–Se/NC achieves an excellent initial specific capacity of 1165.9 m Ah·g^(-1)at 1.0 A·g^(-1),and the reversible capacity of Fe–Co–Se/NC anode is 1247.4 m Ah·g^(-1)after 550 cycles.It is attributed to that the uniform composite of bimetallic selenides and N-doped carbon can effectively tune redox active sites,the stable 3D structure of Fe–Co–Se/NCs guarantees the structural stability and wettability of the electrolyte,and the uniform distribution of Fe–Co–S nanoparticles in size esuppresses the volume expansion and accelerates the electrochemical reaction kinetics.
基金financially supported by the National Key Research and Development Program of China (2017YFA0208200)the National Natural Science Foundation of China (52102100,22022505 and 21872069)+4 种基金the Natural Science Foundation of Jiangsu Province (BK20181469)Guangdong Basic and Applied Basic Research Foundation (2020A1515110035)the Fundamental Research Funds for the Central Universities (0205-14380266,0205-14380272)the Scientific and Technological Innovation Special Fund for Carbon Peak and Carbon Neutrality of Jiangsu Province (BK20220008)the 2021 Suzhou Gusu Leading Talents of Science and Technology Innovation and Entrepreneurship in Wujiang District。
文摘To solve the environmental pollution and low yield during the sythesis of zeolitic imidazolate frameworks(ZIFs)and their derived materials,a KOH-assisted aqueous strategy is proposed to synthesize cobalt zeolitic imidazolate framework(ZIF-67)polyhedrons,which are used as precursors to prepare cobalt selenide/carbon composites with different crystal phases(Co_(0.85)Se,CoSe_2).When evaluated as anode material for lithium ion batteries,Co_(0.85)Se/C composites deliver a reversible capacity of 758.7 m A·h·g^(-1)with a capacity retention rate of 90.5%at 1.0 A·g^(-1)after 500 cycles,and the superior rate capability is 620 m A·h·g^(-1)at 2.0 A·g^(-1).The addition of KOH accelerates the production of ZIF-67 crystals by boosting deprotonation of dimethylimidazole,resulting in rapid growth and structures transition from two-dimensional to three-dimensional of ZIF-67 in aqueous solution,which greatly promotes the application of MOFs in the field of energy storage and conversion.
基金the support from the National Natural Science Foundation of China(Grant No.51971090 and U21A20311)。
文摘The construction of stable cathode electrolyte interphase(CEI)is the key to improve the NCM811 particle structure and interfacial stability via electrolyte engineering.In He’s work,lithium hexamethyldisilazide(LiHMDS)as the electrolyte additive is proposed to facilitate the generation of stable CEI on NCM811 cathode surface and eliminate H_(2)O and HF in the electrolyte at the same time,which boosts the cycling performance of Li||NCM811 battery up to 1000 or 500 cycles with 4.5 V cut-off voltage at 25 or 60℃.
基金supported by the National Natural Science Foundation of China(Nos.21771164,U1804129)the Natural Science Foundation of Henan Province(No.222300420525)the Zhongyuan Youth Talent Support Program of Henan Province
文摘Sodium-ion battery is a potential application system for large-scale energy storage due to the advantage of higher nature abundance and lower production cost of sodium-based materials.However,there exist inevitably the safety problems such as flammability due to the use of the same type of organic liquid electrolyte with lithium-ion battery.Gel polymer electrolytes are being considered as an effective solution to replace conventional organic liquid electrolytes for building safer sodium-ion batteries.In this review paper,the authors present a comprehensive overview of the research progress in electrochemical and physical properties of the gel polymer electrolyte-based sodium batteries.The gel polymer electrolytes based on different polymer hosts namely poly(ethylene oxide),poly(acrylonitrile),poly(methyl methacrylate),poly(vinylidene fluoride),poly(vinylidene fluoride-hexafluoro propylene),and other new polymer networks are summarized.The ionic conductivity,ion transference number,electrochemical window,thermal stability,mechanical property,and interfacial issue with electrodes of gel polymer electrolytes,and the corresponding influence factors are described in detail.Furthermore,the ion transport pathway and ion conduction mechanism are analyzed and discussed.In addition,the advanced gel polymer electrolyte systems including flame-retardant polymer electrolytes,composite gel polymer electrolytes,copolymerization,single-ion conducting polymer electrolytes,etc.with more superior and functional performance are classified and summarized.Finally,the application prospects,development opportunities,remaining challenges,and possible solutions are discussed.
基金supported by the National Natural Science Foundation of China(Nos.22179077,51774251,21908142)Shanghai Science and Technology Commission’s“2020 Science and Technology In-novation Action Plan”(No.20511104003)Natural Science Foundation in Shanghai(No.21ZR1424200)。
文摘Due to its high operational voltage and energy density,P2-type Na_(0.67)Ni_(0.3)Mn_(0.7)O_(2) has become a leading cathode material for sodium-ion batteries(SIBs),which is an ideal option for large-scale energy storage.However,the practical application of P2-type Na_(0.67)Ni_(0.3)Mn_(0.7)O_(2) is limited by the capacity constraints and unwanted phase transitions,presenting significant challenges to the widespread application of SIBs.To address these challenges and optimize the electrochemical properties of the P2 phase cathode material,this study proposes a Cu and Zn co-doped strategy to improve the electrochemical performance.The incorporation of Cu/Zn can stabilize the P2-phase structure against P2-O2 phase transitions,thus enhancing its electrochemical properties.The as-obtained P2-type Na0.67[Ni_(0.3)Mn_(0.58)Cu_(0.09)Zn_(0.03)]O_(2) cathode material shows an impressive cycling stability,maintaining 80%capacity retention after 1000 cycles at 2 C.The cyclic voltammetry(CV)tests show that the Cu^(2+)/Cu^(3+)redox reaction is also involved in charge compensation during the charge/discharge process.
基金This work is sponsored by NSAF joint Fund(U1830106)Science and Technology Innovation 2025 Major Program of Ningbo(2018B10061)National Natural Science Foundation of China(U1632114,51901205),and K.C.Wong Magna Fund in Ningbo University.
文摘Aqueous ammonium ion batteries are regarded as eco-friendly and sustainable energy storage systems.And applicable host for NH_(4)^(+)in aqueous solution is always in the process of development.On the basis of density functional theory calcula-tions,the excellent performance of NH_(4)^(+)insertion in Prussian blue analogues(PBAs)is proposed,especially for copper hexacyanoferrate(CuHCF).In this work,we prove the outstanding cycling and rate performance of CuHCF via electrochemical analyses,delivering no capacity fading during ultra-long cycles of 3000 times and high capacity retention of 93.6%at 50 C.One of main contributions to superior performance from highly reversible redox reaction and structural change is verified during the ammoniation/de-ammoniation progresses.More importantly,we propose the NH_(4)^(+)diffusion mechanism in CuHCF based on con-tinuous formation and fracture of hydrogen bonds from a joint theoretical and experimental study,which is another essential reason for rapid charge transfer and superior NH_(4)^(+)storage.Lastly,a full cell by coupling CuHCF cathode and polyaniline anode is constructed to explore the practical application of CuHCF.In brief,the outstanding aqueous NH_(4)^(+)storage in cubic PBAs creates a blueprint for fast and sustainable energy storage.
基金supported by the Tianjin Committee of Science and Technology (No.14JCZDJC32400)Tianjin Science and Technology Innovation Platform Program (No.14TXGCCX00017)
文摘Transition metal oxides have been actively exploited for application in lithium ion batteries due to their facile synthesis,high specific capacity,and environmental-friendly.In this paper,Fe3O4@TiO2@C yolk-shell(Y-S)spheres,used as anode material for lithium ion batteries,were successfully fabricated by Stober method.XRD patterns reveal that Fe3O4@TiO2@C Y-S spheres possess a good crystallinity.But the diffraction peaks’intensity of Fe3O4 crystals in the composites is much weaker than that of bare Fe3O4 spheres,indicating that the outer anatase TiO2@C layer can cover up the diffraction peaks of inner Fe3O4 spheres.The yolk-shell structure of Fe3O4@TiO2@C spheres is further characterized by TEM,HAADFSTEM,and EDS mapping.The yolk-shell structure is good for improving the cycling stability of the inner Fe3O4 spheres during lithium ions insertion-extraction processes.When tested at 200 mA/g,the Fe3O4@TiO2@C Y-S spheres can provide a stable discharge capacity of 450 mAh/g over 100 cycles,which is much better than that of bare Fe3O4 spheres and TiO2@C spheres.Furthermore,cyclic voltammetry curves show that the composites have a good cycling stability compared to bare Fe3O4 spheres.
基金financially supported by the National Natural Science Foundation for Excellent Young Scholars of China (No. 51522402)the National Postdoctoral Program for Innovative Talents of China (No. BX20180034)+2 种基金the National Natural Science Foundation of China (No. 51902020)the Fundamental Research Funds for the Central Universities (No. FRF-TP-18-045A1)the China Postdoctoral Science Foundation (No. 2018M641192)
文摘Currently,developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge.In the present work,few-layer hexagonal boron nitride nanosheets(h-BNNSs)with a thickness of 2−4 atomic layers were fabricated via vacuum freeze-drying and nitridation.Then,the h-BNNSs/reduced graphene oxide(rGO)composite were further prepared using a hydrothermal method.Due to the combination of two two-dimensional(2D)van der Waals-bonded materials,the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from−10 to 50℃.When the electrodes worked in a neutral aqueous electrolyte(1 M Na2SO4),they showed a great stable cycling performance with almost 107%reservation of the initial capacitance at 0℃ and 111% at 50℃ for 5000 charge−discharge cycles.
基金This project is supported by National Innovation Foundation for TechnologyBased Firms, China (No.01C26213300872).
文摘The multi-impact characteristics and failure mechanism of two kinds of automotive engine chain made in China are studied through engine assembly and road-drive tests. The worn surface morphologies of rubbing area between pin, bush and roller are also analyzed based on scanning electron microscope. The results show that the main wear mechanism of automotive engine chain is fatigue wear, and its failure mechanism is the forming, extending and flaking of cracks on top layer of pin and bush. In addition, the material, hot-treatment method and shaping technique for roller have a great influence upon the resistance to multi-impact. Ensuring sufficient strength and plasticity of roller, as well as adopting suitable shaping technique are the effective method to increase its resistance to multi-impact.
基金supported by the Innovation Foundation of BUAA for Ph. D Graduates Provided by Beihang University in China
文摘This work focused on the zinc powder coated with Y(OH)3 microparticles by means of ultrasonic immersion for performance improvement of zinc electrodes in alkaline battery systems.Scanning electron microscopy and other characterization techniques were applied to examine the influence of the ultrasonic power on the sonochemical growth of Y(OH)3 microparticles in direct contact with zinc powder.Electrochemical properties of zinc electrodes containing Y(OH)3 microparticles were discussed through the measurement...
基金supported by the Major Program of Beijing Municipal Natural Science Foundation(No.2110001)the National Natural Science Foundation of China(No.11179001)the National High Technology Research and Development Program(No.2012AA052201)
文摘Silicon is being investigated extensively as an anodic material for next-generation lithium ion batteries for portable energy storage and electric vehicles.However,the large changes in volume during cycling lead to the breakdown of the conductive network in Si anodes and the formation of an unstable solid-electrolyte interface,resulting in capacity fading.Here,we demonstrate nanoparticles with a Si@Mn22.6Si5.4C4@C double-shell structure and the formation of self-organized Si-Mn-C nanocomposite anodes during the lithiation/delithiation process.The anode consists of amorphous Si particles less than 10 nm in diameter and separated by an interconnected conductive/buffer network,which exhibits excellent charge transfer kinetics and charge/discharge performances.A stable specific capacity of 1100 mAh·g-1 at 100 mA·g-1 and a coulombic efficiency of 99.2%after 30 cycles are achieved.Additionally,a rate capacity of 343 mAh·g-1 and a coulombic efficiency of 99.4%at 12000 mA·g-1 are also attainable.Owing to its simplicity and applicability,this strategy for improving electrode performance paves a way for the development of high-performance Si-based anodic materials for lithium ion batteries.
基金support from the National Natural Science Foundation of China(nos.21403202,21233006 and 21473164)the Key Program of the Natural Science Foundation of Hubei Province(no.2015CFA129)+1 种基金the Undergraduate Innovation Training Program of CUG(no.201610491138)the Excellent Youth of CUG Scholars
文摘The lithium–sulfur batteries show the great potential to be the most promising candidate for high energy applications. However, the shuttling of soluble polysulfides deteriorates the battery performance tremendously. To suppress the diffusion of soluble polysulfides, diatomite that has abundant natural three-dimensional ordered pores is incorporated into the cathode to trap polysulfides. The composite cathode material(S-DM-AB for short), including sulfur(S), diatomite(DM), and acetylene black(AB) is prepared by an impregnation method. For comparison, another composite cathode material(S-AB for short) including sulfur and acetylene black is also prepared by the same method. The battery with S-DMAB composite cathode material delivers a discharge capacity of 531.4 m Ah/g after 300 cycles at 2 C with a capacity retention of 51.6% at room temperature. By contrast, the battery with S-AB composite cathode material delivered a capacity of only 196.9 m Ah/g with a much lower capacity retention of 18.6% under the same condition. The addition of diatomite in the cathode is proved to be a cheap and effective way to improve the life time of the lithium sulfur batteries.
基金Funded by the Fundamental Research Funds for the Central Universities(No.2014QNA08)
文摘α-MoO3 nanobelts/carbon nanotubes(CNTs) composites were synthesized by simple hydrothermal method followed by CNTs incorporating, and characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Cyclic voltammogram(CV), electrochemical impedance spectroscopy(EIS), and galvanostatic charge/discharge testing techniques were employed to evaluate the electrochemical behaviors of α-MoO3 nanobelts/CNTs composites. The results exhibited that compared to bare α-MoO3 nanobelts, the α-MoO3 nanobelts/CNTs composites have better electrochemical performances as cathode materials for lithium ion battery, maintaining a reversible specific capacity of 222.2 mAh/g at 0.3 C after 50 cycles, and 74.1% retention of the first reversible capacity. In addition, the Rct value of the α-MoO3 nanobelts/CNTs is 13 Ω, much lower than 66 Ω of the bare α-MoO3 nanobelts. The better electrochemical performances of the α-MoO3 nanobelts/CNTs composites can be attributed to the effects of the high conductive CNTs network.
基金supported by the National Natural Science Foundation of China (No. 52071144, 51822104, 51831009, and 51621001)
文摘Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anodes,a new facile composition and electrode design strategy have been adapted to fabricate a SiO-Sn-Co/graphite(G)anode.It achieves a unique structure where tiny milled SiO-Sn-Co particles are dispersed among two graphite layers.In this hybrid electrode,Sn-Co alloys promoted Li;extraction kinetics,and the holistic reversibility of SiO and graphite enhanced the electrical conductivity.The SiO-Sn-Co/G electrode delivered an average ICE of 77.6%and a reversible capacity of 640 mAh g^(-1)at 800 mA g^(-1),and the capacity retention was above 98%after 100 cycles,which was much higher than that of the SiO with an ICE of 55.3%and a capacity retention of 50%.These results indicated that this was reliable method to improve the reversibility and cycle ability of the SiO anode.Furthermore,based on its easy and feasible fabrication process,it may provide a suitable choice to combine other alloy anodes with the graphite anode.