There is an urgent need to develop high-areal-capacity silicon(Si)anodes with good cycling stability and rate capability for high-energy-density lithium-ion batteries(LIBs).However,this remains a huge challenge due to...There is an urgent need to develop high-areal-capacity silicon(Si)anodes with good cycling stability and rate capability for high-energy-density lithium-ion batteries(LIBs).However,this remains a huge challenge due to large volume expansion-induced mechanical degradation and electrical connectivity loss in thick electrodes.Here,a three-in-one strategy is proposed to achieve high-areal-capacity silicon anodes by constructing a multi-level interconnected 3D porous and robust conductive network that carbon nanofibers and vertical carbon nanosheets tightly encapsulate on the surface of Si nanoparticles(Si NPs)anchored in porous carbon felts.This network accommodates large volume expansion of Si NPs to significantly improve electrode mechanical stability and creates excellent electrical connectivity to boost charge transport in thick electrodes,revealed through Multiphysics field simulations and in situ electrochemical techniques.Therefore,the designed Si anodes achieve superior long-term stability with a capacity of 8.13 mAh cm^(-2)after 500 cycles and an ultrahigh areal capacity of 45.8 mAh cm^(-2).In particular,Ah-level pouch cells demonstrate an impressive capacity retention of 79.34%after 500 cycles at 1 C.Our study offers novel insights and directions for understanding and optimizing high-areal-capacity silicon-carbon composite anodes.展开更多
All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential ...All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.展开更多
Energy storage plays a critical role in sustainable development,with secondary batteries serving as vital technologies for efficient energy conversion and utilization.This review provides a comprehensive summary of re...Energy storage plays a critical role in sustainable development,with secondary batteries serving as vital technologies for efficient energy conversion and utilization.This review provides a comprehensive summary of recent advancements across various battery systems,including lithium-ion,sodium-ion,potassium-ion,and multivalent metal-ion batteries such as magnesium,zinc,calcium,and aluminum.Emerging technologies,including dual-ion,redox flow,and anion batteries,are also discussed.Particular attention is given to alkali metal rechargeable systems,such as lithium-sulfur,lithium-air,sodium-sulfur,sodium-selenium,potassium-sulfur,potassium-selenium,potassium-air,and zinc-air batteries,which have shown significant promise for high-energy applications.The optimization of key components—cathodes,anodes,electrolytes,and interfaces—is extensively analyzed,supported by advanced characterization techniques like time-of-flight secondary ion mass spectrometry(TOF-SIMS),synchrotron radiation,nuclear magnetic resonance(NMR),and in-situ spectroscopy.Moreover,sustainable strategies for recycling spent batteries,including pyrometallurgy,hydrometallurgy,and direct recycling,are critically evaluated to mitigate environmental impacts and resource scarcity.This review not only highlights the latest technological breakthroughs but also identifies key challenges in reaction mechanisms,material design,system integration,and waste battery recycling,and presents a roadmap for advancing high-performance and sustainable battery technologies.展开更多
High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,ch...High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency remain.Herein,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning method.Viscous composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,respectively.MnO_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning property.The obtained fiber electrodes demonstrate favorable uniformity and flexibility.Benefiting from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 cycles.Moreover,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending cycles.This work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.展开更多
Lithium metal is considered the ideal anode material for Li-ion-based batteries because it exhibits the highest specific capacity and lowest redox potential for this type of cells. However, growth of Li dendrites, uns...Lithium metal is considered the ideal anode material for Li-ion-based batteries because it exhibits the highest specific capacity and lowest redox potential for this type of cells. However, growth of Li dendrites, unstable solid electrolyte interphases, low Coulombic efficiencies, and safety hazards have significantly hindered the practical application of metallic Li anodes. Herein, we propose a three-dimensional （3D） carbon nanotube sponge （CNTS） as a Li deposition host. The high specific surface area of the CNTS enables homogenous charge distribution for Li nucleation and minimizes the effective current density to overcome dendrite growth. An additional conformal A1203 layer on the CNTS coated by atomic layer deposition （ALD） robustly protects the Li metal electrode/electrolyte interface due to the good chemical stability and high mechanical strength of the layer. The Li@ALD-CNTS electrode exhibits stable voltage profiles with a small overpotential ranging from 16 to 30 mV over 100 h of cycling at 1.0 mA·cm^-2. Moreover, the electrodes display a dendrite-free morphology after cycling and a Coulombic efficiency of 92.4% over 80 cycles at 1.0 mA·cm^-2 in an organic carbonate electrolyte, thus demonstrating electrochemical stability superior to that of planar current collectors. Our results provide an important strategy for the rational design of current collectors to obtain stable Li metal anodes.展开更多
High performance and low-cost electrocatalysts for overall water splitting,i.e.,catalyzing hydrogen and oxygen evolution reactions with the same material,are of great importance for large-scale,renewable energy conver...High performance and low-cost electrocatalysts for overall water splitting,i.e.,catalyzing hydrogen and oxygen evolution reactions with the same material,are of great importance for large-scale,renewable energy conversion processes.Here,we report an ultrafast(~7 ms)synthesis tech nique for tran sition metal chalcoge nide n anoparticles assisted by high temperature treatme nt.As a proof of con cept,we dem on strate that cobalt sulfide(~20 nm in diameter)@few-layer graphe ne(~2 nm in thick ness)core-shell nan oparticles embedded in RGO nano sheets exhibit remarkable bifunctional electrocatalytic activity and stability for overall water splitting,which is comparable to commercial 40 wt.%platinum/carbon(Pt/C)electrocatalysts.After 60 h of continuous operation,10 mA crrT?water splitting current density can still be achieved at a low potential of^1.77 V without any activity decay,which is among the most active for non-noble material based electrocatalysts.The presented study provides prospects in synthesizing highly efficient bifunctional electrocatalysts for large-scale energy conversion application via a simple yet efficient technique.展开更多
Tin selenides have been attracting great attention as anode materials for the state-of-the-art rechargeable sodium-ion batteries(SIBs)due to their high theoretical capacity and low cost.However,they deliver unsatisfac...Tin selenides have been attracting great attention as anode materials for the state-of-the-art rechargeable sodium-ion batteries(SIBs)due to their high theoretical capacity and low cost.However,they deliver unsatisfactory performance in practice,owing to their intrinsically low conductivity,sluggish kinetics and volume expansion during the charge-discharge process.Herein,we demonstrate the synthesis of SnSe2 nanocrystals coupled with hierarchical porous carbon(SnSe2 NCs/C)microspheres for boosting SIBs in terms of capacity,rate ability and durability.The unique structure of SnSe2 NCs/C possesses several advantages,including inhibiting the agglomeration of SnSe2 nanoparticles,relieving the volume expansion,accelerating the diffusion kinetics of electrons/ions,enhancing the contact area between the electrode and electrolyte and improving the structural stability of the composite.As a result,the as-obtained SnSe2 NCs/C microspheres show a high reversible capacity(565 mA h g^-1 after 100 cycles at 100 mA g^-1),excellent rate capability,and long cycling life stability(363 mA h g^-1 at1 A g^-1 after 1000 cycles),which represent the best performances among the reported SIBs based on SnSe2-based anode materials.展开更多
CONSPECTUS:With the development of nanotechnology and characterization techniques,it has been realized that the reactivity of metal nanoparticles mainly depends on some unsaturated coordination atoms on the surface.Ho...CONSPECTUS:With the development of nanotechnology and characterization techniques,it has been realized that the reactivity of metal nanoparticles mainly depends on some unsaturated coordination atoms on the surface.However,only a small fraction of the surface exposed atoms can access the reactants and act as reactive sites,resulting in low utilization of metal atoms.Moreover,due to the complex structure of metal nanoparticles,the metal atoms exposed on the surface are likely to be in different chemical environments and may act as multiple active centers to catalyze the reactants,which brings great difficulties in the establishment of the structure−activity relationship of metal nanoparticles.展开更多
Binary metal chalcogenides(BMCs)have shown better electrochemical performance compared with their mono metal counterparts owing to their abundant phase interfaces,higher active sites,faster electrochemical kinetics an...Binary metal chalcogenides(BMCs)have shown better electrochemical performance compared with their mono metal counterparts owing to their abundant phase interfaces,higher active sites,faster electrochemical kinetics and higher electronic conductivity.Nevertheless,their performance still undergoes adverse decline during electrochemical processes mainly due to poor intrinsic ionic conductivities,large volume expansions,and structural agglomeration and fracture.To tackle these problems,various strategies have been applied to engineer the BMC nanostructures to obtain optimized electrode materials.However,the lack of understanding of the electrochemical response of BMCs still hinders their large-scale application.This review not only highlights the recent progress and development in the preparation of BMC-based electrode materials but also explains the kinetics to further understand the relation between structure and performance.It will also explain the engineering of BMCs through nanostructuring and formation of their hybrid structures with various carbonaceous materials and three-dimensional(3 D)templates.The review will discuss the detailed working mechanism of BMC-based nanostructures in various electrochemical energy storage(EES)systems including supercapacitors,metal-ion batteries,metal-air batteries,and alkaline batteries.In the end,major challenges and prospective solutions for the development of BMCs in EES devices are also outlined.We believe that the current review will provide a guideline for tailoring BMCs for better electrochemical devices.展开更多
Despite various 2H-MoS/carbon hybrid nanostructures have been constructed and committed to improve the performance for sodium-ion batteries(SIBs),they still show the limited cycle stability due to the relatively large...Despite various 2H-MoS/carbon hybrid nanostructures have been constructed and committed to improve the performance for sodium-ion batteries(SIBs),they still show the limited cycle stability due to the relatively large volumetric expansion during the charge-discharge process Herein,we report the construction of cobalt-doped few-layered 1T-MoS2 nanosheets embedded in N,S-doped carbon(CMS/NSC)nanobowls derived from metal-organic framework(MOF)precursor via a simple in situ sulfurization process.This unique hierarchical structure enables the uniformly dispersed Co-doped 1T-MoS2 nanosheets intimately couple with the highly conductive carbon nanobowls,thus efficiently preventing the aggregation.In particular,the Co-doping plays a crucial role in maintaining the integrity of structure for MoS2 during cycling tests,confirmed by first-principles calculations.Compared with pristine MoS2,the volume deformation of Co-doped MoS2 can be shrunk by a prominent value of 52%during cycling.Furthermore,the few-layered MoS2 nanosheets with 1T metalic phase endow higher conductivity,and thus can surpass its counterpart 2H semiconducting phase in battery performance.By virtue of the synergistic effect of stable structure,appropriate doping and high conductivity,the resulting CMS/NSC hybrid shows superior rate capability and cycle stability.The capacity of CMS/NSC can still be 235.9 mAh·g^-1 even at 25 A·g^-1,which is 51.3%of the capacity at 0.2 A·g^-1.Moreover,the capacity can still remain 218.6 mAh·g^-1 even over 8,240 cycles at 5 Ag·g^-1 with a low decay of 0.0044%per cycle,one of the best performances among the reportec MoS2-based anode materials for SIBs.展开更多
Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterial...Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterials are the most promising pseudocapacitive materials for high volumetric capacitance electrodes. However, they are poorly conductive and prone to self-stacking, which results in unsatisfactory electrochemical performance. In this work, large-scale V2O5·nH2O ultrathin nanosheets are synthesized by a facile and scalable method and transformed into layered and compact composite films with one-dimensional carbon nanotubes (CNTs). The self-standing films show an optimized volumetric capacitance of 521.0Fcm^-3 with only 10 wt% of CNTs, which is attributed to dramatically enhanced electrical conductivity beyond the electrical percolation threshold, high dispersion of pseudocapacitive V2O5·nH2O nanosheets, and high mass density of the films. All-solid-state flexible SCs made of V2O5·nH2O/CNTs films show a maximum energy density of 17.4WhL^-1.展开更多
锂金属具有氧化还原电位低、理论比容量大等优点,是下一代高比能电池极具发展前景的负极.然而,锂枝晶生长和低可逆性严重阻碍了高比能锂金属电池的发展.受启发于生物细胞膜结构,本文采用涂布法在锂金属表面成功构筑了一种具有仿生离子...锂金属具有氧化还原电位低、理论比容量大等优点,是下一代高比能电池极具发展前景的负极.然而,锂枝晶生长和低可逆性严重阻碍了高比能锂金属电池的发展.受启发于生物细胞膜结构,本文采用涂布法在锂金属表面成功构筑了一种具有仿生离子通道的人工界面固体电解质层(CAL).该CAL中大量带负电荷的离子通道可以促进锂离子均匀、快速的输运,有利于稳定、均匀地进行锂沉积/剥离.此外,在循环过程中,CAL底部与锂金属发生原位转化反应,生成了一层富含亲锂性无机组分的过渡层,促进了锂离子的扩散并抑制了锂金属与电解液的连续副反应.因此,形成的具有双面神结构的人工界面固体电解质层(CAJL)使得锂金属负极可以在10 mA cm^(-2)的高电流密度和10 mAh cm^(-2)的高面积容量下长期稳定循环.更重要的是,基于CAJL功能化锂金属负极的锂硫软包电池实现了429.2 Wh kg^(-1)的高能量密度.展开更多
Redox flow batteries(RFBs)that employ sustainable,abundant,and structure-tunable redox-active species are of great interest for large-scale energy storage.As a vital class of redox-active species,metal coordination co...Redox flow batteries(RFBs)that employ sustainable,abundant,and structure-tunable redox-active species are of great interest for large-scale energy storage.As a vital class of redox-active species,metal coordination complexes(MCCs)possessing the properties of both the organic ligands and transition metal ion centers are attracting increasing attention due to the advantages of multielectron charge transfer,high structural tailorability,and reduced material crossover.Herein,we present a critical overview of RFBs that employ MCCs as redox-active materials in both aqueous and nonaqueous mediums.The progress is comprehensively summarized,including the design strategies,solubility characteristics,electrochemical properties,and battery cycling performance of MCCs.Emphasis is placed on the ligand selection and modification strategies used to tune the critical properties of MCCs,including their redox potential,solubility,cycling stability,and electron transfer redox reactions,to achieve stable cycled RFBs with a high energy density.Furthermore,we discuss the current challenges and perspectives related to the development of MCC-based RFBs for large-scale energy storage implementations.展开更多
基金supported by the Jiangyin-SUSTech Innovation Fundthe National Natural Science Foundation of China (No. 22309078 and 52302261)+3 种基金the Shenzhen Key Laboratory of Advanced Energy Storage (ZDSYS20220401141000001)the Shenzhen Science and Technology Plan Project(No. SGDX20230116091644003)the Guangdong Basic and Applied Basic Research Foundation (2023B1515120069)the Pico Center at SUSTech Core Research Facilities,which is supported by the Presidential Fund and the Development and Reform Commission of Shenzhen Municipality
文摘There is an urgent need to develop high-areal-capacity silicon(Si)anodes with good cycling stability and rate capability for high-energy-density lithium-ion batteries(LIBs).However,this remains a huge challenge due to large volume expansion-induced mechanical degradation and electrical connectivity loss in thick electrodes.Here,a three-in-one strategy is proposed to achieve high-areal-capacity silicon anodes by constructing a multi-level interconnected 3D porous and robust conductive network that carbon nanofibers and vertical carbon nanosheets tightly encapsulate on the surface of Si nanoparticles(Si NPs)anchored in porous carbon felts.This network accommodates large volume expansion of Si NPs to significantly improve electrode mechanical stability and creates excellent electrical connectivity to boost charge transport in thick electrodes,revealed through Multiphysics field simulations and in situ electrochemical techniques.Therefore,the designed Si anodes achieve superior long-term stability with a capacity of 8.13 mAh cm^(-2)after 500 cycles and an ultrahigh areal capacity of 45.8 mAh cm^(-2).In particular,Ah-level pouch cells demonstrate an impressive capacity retention of 79.34%after 500 cycles at 1 C.Our study offers novel insights and directions for understanding and optimizing high-areal-capacity silicon-carbon composite anodes.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(2023B0303000002)the National Natural Science Foundation of China(No.52206089)+3 种基金the Guangdong Basic and Applied Basic Research Foundation(2024A1515010288,2023B1515120005)the Natural Science Foundation of Shenzhen(JCYJ20230807093315033)the Shenzhen Engineering Research Center,Southern University of Science and Technology(No.XMHT20230208003)high level of special funds(G03034K001)。
文摘All-vanadium flow batteries(VFBs)are one of the most promising large-scale energy storage technologies.Conducting an operando quantitative analysis of the polarizations in VFBs under different conditions is essential for developing high power density batteries.Here,we employ an operando decoupling method to quantitatively analyze the polarizations in each electrochemical and chemical reaction of VFBs under different catalytic conditions.Results show that the reduction reaction of V^(3+)presents the largest activation polarization,while the reduction reaction of VO_(2)^(+)primarily contributes to concentration polarizations due to the formation of the intermediate product V_(2)O_(3)^(3+).Additionally,it is found that the widely used electrode catalytic methods,incorporating oxygen functional groups and electrodepositing Bi,not only enhance the reaction kinetics but also exacerbate concentration polarizations simultaneously,especially during the discharge process.Specifically,in the battery with the high oxygen-containing electrodes,the negative side still accounts for the majority of activation loss(75.3%)at 200 mA cm^(-2),but it comes down to 36,9% after catalyzing the negative reactions with bismuth.This work provides an effective way to probe the limiting steps in flow batteries under various working conditions and offers insights for effectively enhancing battery performance for future developments.
基金supported by the National Natural Science Foundation of China(Nos.U21A20311 and 22409147)。
文摘Energy storage plays a critical role in sustainable development,with secondary batteries serving as vital technologies for efficient energy conversion and utilization.This review provides a comprehensive summary of recent advancements across various battery systems,including lithium-ion,sodium-ion,potassium-ion,and multivalent metal-ion batteries such as magnesium,zinc,calcium,and aluminum.Emerging technologies,including dual-ion,redox flow,and anion batteries,are also discussed.Particular attention is given to alkali metal rechargeable systems,such as lithium-sulfur,lithium-air,sodium-sulfur,sodium-selenium,potassium-sulfur,potassium-selenium,potassium-air,and zinc-air batteries,which have shown significant promise for high-energy applications.The optimization of key components—cathodes,anodes,electrolytes,and interfaces—is extensively analyzed,supported by advanced characterization techniques like time-of-flight secondary ion mass spectrometry(TOF-SIMS),synchrotron radiation,nuclear magnetic resonance(NMR),and in-situ spectroscopy.Moreover,sustainable strategies for recycling spent batteries,including pyrometallurgy,hydrometallurgy,and direct recycling,are critically evaluated to mitigate environmental impacts and resource scarcity.This review not only highlights the latest technological breakthroughs but also identifies key challenges in reaction mechanisms,material design,system integration,and waste battery recycling,and presents a roadmap for advancing high-performance and sustainable battery technologies.
基金financially supported by the National Science Fund for Distinguished Young Scholars(52025133)the Beijing Natural Science Foundation(JQ18005)+7 种基金the Tencent Foundation through the XPLORER PRIZE,the National Key R&D Program of China(2017YFA0206701)the BIC-ESAT fundingthe financial support of the Central Universities(2232020D-13)the Shanghai Sailing Program(20YF1400700)the National Natural Science Foundation of China(52003045)the financial support from the Young Elite Scientist Sponsorship Program by CAST(2019QNRC001)the“1000-Plan program”of Shaanxi Provincethe“Young Talent Support Plan”of Xi’an Jiaotong University。
文摘High-performance flexible one-dimensional(1D)electrochemical energy storage devices are crucial for the applications of wearable electronics.Although much progress on various 1D energy storage devices has been made,challenges involving fabrication cost,scalability,and efficiency remain.Herein,a highperformance flexible all-fiber zinc-ion battery(ZIB)is fabricated using a low-cost,scalable,and efficient continuous wet-spinning method.Viscous composite inks containing cellulose nanofibers/carbon nanotubes(CNFs/CNTs)binary composite network and either manganese dioxide nanowires(MnO_(2) NWs)or commercial Zn powders are utilized to spinning fiber cathodes and anodes,respectively.MnO_(2) NWs and Zn powders are uniformly dispersed in the interpenetrated CNFs/CNTs fibrous network,leading to homogenous composite inks with an ideal shear-thinning property.The obtained fiber electrodes demonstrate favorable uniformity and flexibility.Benefiting from the well-designed electrodes,the assembled flexible fiber-shaped ZIB delivers a high specific capacity of 281.5 m Ah g^(-1) at 0.25 A g^(-1) and displays excellent cycling stability over 400 cycles.Moreover,the wet-spun fiber-shaped ZIBs achieve ultrahigh gravimetric and volumetric energy densities of 47.3 Wh kg^(-1) and 131.3 m Wh cm^(-3),respectively,based on both cathode and anode and maintain favorable stability even after 4000 bending cycles.This work offers a new concept design of 1D flexible ZIBs that can be potentially incorporated into commercial textiles for wearable and portable electronics.
文摘Lithium metal is considered the ideal anode material for Li-ion-based batteries because it exhibits the highest specific capacity and lowest redox potential for this type of cells. However, growth of Li dendrites, unstable solid electrolyte interphases, low Coulombic efficiencies, and safety hazards have significantly hindered the practical application of metallic Li anodes. Herein, we propose a three-dimensional （3D） carbon nanotube sponge （CNTS） as a Li deposition host. The high specific surface area of the CNTS enables homogenous charge distribution for Li nucleation and minimizes the effective current density to overcome dendrite growth. An additional conformal A1203 layer on the CNTS coated by atomic layer deposition （ALD） robustly protects the Li metal electrode/electrolyte interface due to the good chemical stability and high mechanical strength of the layer. The Li@ALD-CNTS electrode exhibits stable voltage profiles with a small overpotential ranging from 16 to 30 mV over 100 h of cycling at 1.0 mA·cm^-2. Moreover, the electrodes display a dendrite-free morphology after cycling and a Coulombic efficiency of 92.4% over 80 cycles at 1.0 mA·cm^-2 in an organic carbonate electrolyte, thus demonstrating electrochemical stability superior to that of planar current collectors. Our results provide an important strategy for the rational design of current collectors to obtain stable Li metal anodes.
文摘High performance and low-cost electrocatalysts for overall water splitting,i.e.,catalyzing hydrogen and oxygen evolution reactions with the same material,are of great importance for large-scale,renewable energy conversion processes.Here,we report an ultrafast(~7 ms)synthesis tech nique for tran sition metal chalcoge nide n anoparticles assisted by high temperature treatme nt.As a proof of con cept,we dem on strate that cobalt sulfide(~20 nm in diameter)@few-layer graphe ne(~2 nm in thick ness)core-shell nan oparticles embedded in RGO nano sheets exhibit remarkable bifunctional electrocatalytic activity and stability for overall water splitting,which is comparable to commercial 40 wt.%platinum/carbon(Pt/C)electrocatalysts.After 60 h of continuous operation,10 mA crrT?water splitting current density can still be achieved at a low potential of^1.77 V without any activity decay,which is among the most active for non-noble material based electrocatalysts.The presented study provides prospects in synthesizing highly efficient bifunctional electrocatalysts for large-scale energy conversion application via a simple yet efficient technique.
基金supported by the National Key R&D Research Program of China (2016YFB0100201)Beijing Natural Science Foundation (JQ18005)+2 种基金the National Natural Science Foundation of China (51671003, 21802003)China Postdoctoral Science Foundation (2019TQ0001)the start-up supports from Peking University and Young Thousand Talented Program
文摘Tin selenides have been attracting great attention as anode materials for the state-of-the-art rechargeable sodium-ion batteries(SIBs)due to their high theoretical capacity and low cost.However,they deliver unsatisfactory performance in practice,owing to their intrinsically low conductivity,sluggish kinetics and volume expansion during the charge-discharge process.Herein,we demonstrate the synthesis of SnSe2 nanocrystals coupled with hierarchical porous carbon(SnSe2 NCs/C)microspheres for boosting SIBs in terms of capacity,rate ability and durability.The unique structure of SnSe2 NCs/C possesses several advantages,including inhibiting the agglomeration of SnSe2 nanoparticles,relieving the volume expansion,accelerating the diffusion kinetics of electrons/ions,enhancing the contact area between the electrode and electrolyte and improving the structural stability of the composite.As a result,the as-obtained SnSe2 NCs/C microspheres show a high reversible capacity(565 mA h g^-1 after 100 cycles at 100 mA g^-1),excellent rate capability,and long cycling life stability(363 mA h g^-1 at1 A g^-1 after 1000 cycles),which represent the best performances among the reported SIBs based on SnSe2-based anode materials.
基金supported by the National Key R&D Program of China(No.2021YFA1501001)the National Science Fund for Distinguished Young Scholars(No.52025133)+1 种基金the Beijing Natural Science Foundation(Z220020)Tencent Foundation through the XPLORER PRIZE,CNPC Innovation Found(2021DQ02-1002).
文摘CONSPECTUS:With the development of nanotechnology and characterization techniques,it has been realized that the reactivity of metal nanoparticles mainly depends on some unsaturated coordination atoms on the surface.However,only a small fraction of the surface exposed atoms can access the reactants and act as reactive sites,resulting in low utilization of metal atoms.Moreover,due to the complex structure of metal nanoparticles,the metal atoms exposed on the surface are likely to be in different chemical environments and may act as multiple active centers to catalyze the reactants,which brings great difficulties in the establishment of the structure−activity relationship of metal nanoparticles.
基金supported by the National Natural Science Fund for Distinguished Young Scholars(52025133)the Tencent Foundation through the XPLORER PRIZE,Beijing Natural Science Foundation(JQ18005)+2 种基金the National Natural Science Foundation of China(52125307 and 11974023)the Fund of the State Key Laboratory of Solidification Processing in Northwestern Polytechnic University(NWPU)(SKLSP202004)the Key Area R&D Program of Guangdong Province(2018B030327001 and 2018B010109009)。
文摘Binary metal chalcogenides(BMCs)have shown better electrochemical performance compared with their mono metal counterparts owing to their abundant phase interfaces,higher active sites,faster electrochemical kinetics and higher electronic conductivity.Nevertheless,their performance still undergoes adverse decline during electrochemical processes mainly due to poor intrinsic ionic conductivities,large volume expansions,and structural agglomeration and fracture.To tackle these problems,various strategies have been applied to engineer the BMC nanostructures to obtain optimized electrode materials.However,the lack of understanding of the electrochemical response of BMCs still hinders their large-scale application.This review not only highlights the recent progress and development in the preparation of BMC-based electrode materials but also explains the kinetics to further understand the relation between structure and performance.It will also explain the engineering of BMCs through nanostructuring and formation of their hybrid structures with various carbonaceous materials and three-dimensional(3 D)templates.The review will discuss the detailed working mechanism of BMC-based nanostructures in various electrochemical energy storage(EES)systems including supercapacitors,metal-ion batteries,metal-air batteries,and alkaline batteries.In the end,major challenges and prospective solutions for the development of BMCs in EES devices are also outlined.We believe that the current review will provide a guideline for tailoring BMCs for better electrochemical devices.
基金This work was financially supported by the National Key R&D Program of China(No.2016YFB0100200)Young Thousand Talents Program,the Open Project Foundation of State Key Laboratory of Chemical Resource Engineering,the China Postdoctoral Science Foundation(No.2017M610018)the National Natural Science Foundation of China(No.51671003),Start-up Funding from Peking University.
文摘Despite various 2H-MoS/carbon hybrid nanostructures have been constructed and committed to improve the performance for sodium-ion batteries(SIBs),they still show the limited cycle stability due to the relatively large volumetric expansion during the charge-discharge process Herein,we report the construction of cobalt-doped few-layered 1T-MoS2 nanosheets embedded in N,S-doped carbon(CMS/NSC)nanobowls derived from metal-organic framework(MOF)precursor via a simple in situ sulfurization process.This unique hierarchical structure enables the uniformly dispersed Co-doped 1T-MoS2 nanosheets intimately couple with the highly conductive carbon nanobowls,thus efficiently preventing the aggregation.In particular,the Co-doping plays a crucial role in maintaining the integrity of structure for MoS2 during cycling tests,confirmed by first-principles calculations.Compared with pristine MoS2,the volume deformation of Co-doped MoS2 can be shrunk by a prominent value of 52%during cycling.Furthermore,the few-layered MoS2 nanosheets with 1T metalic phase endow higher conductivity,and thus can surpass its counterpart 2H semiconducting phase in battery performance.By virtue of the synergistic effect of stable structure,appropriate doping and high conductivity,the resulting CMS/NSC hybrid shows superior rate capability and cycle stability.The capacity of CMS/NSC can still be 235.9 mAh·g^-1 even at 25 A·g^-1,which is 51.3%of the capacity at 0.2 A·g^-1.Moreover,the capacity can still remain 218.6 mAh·g^-1 even over 8,240 cycles at 5 Ag·g^-1 with a low decay of 0.0044%per cycle,one of the best performances among the reportec MoS2-based anode materials for SIBs.
基金supported by the National Natural Science Foundation of China (51702048 and 21603157)the National Basic Research Program of China (2015CB932600)Jiangxi Provincial Department of Education (GJJ170459 and GJJ170457)
文摘Flexible supercapacitors (SCs) are attractive energy storage devices for wearable electronics, but their applications are hindered by their low volumetric energy densities. Two dimensional (2D) non-carbon nanomaterials are the most promising pseudocapacitive materials for high volumetric capacitance electrodes. However, they are poorly conductive and prone to self-stacking, which results in unsatisfactory electrochemical performance. In this work, large-scale V2O5·nH2O ultrathin nanosheets are synthesized by a facile and scalable method and transformed into layered and compact composite films with one-dimensional carbon nanotubes (CNTs). The self-standing films show an optimized volumetric capacitance of 521.0Fcm^-3 with only 10 wt% of CNTs, which is attributed to dramatically enhanced electrical conductivity beyond the electrical percolation threshold, high dispersion of pseudocapacitive V2O5·nH2O nanosheets, and high mass density of the films. All-solid-state flexible SCs made of V2O5·nH2O/CNTs films show a maximum energy density of 17.4WhL^-1.
基金financially supported by the Research Grants Council of the Hong Kong Special Administrative Region,China(T23-601/17-R)supported by the Fundamental Research Funds for the Central Universities(D5000220443)。
文摘锂金属具有氧化还原电位低、理论比容量大等优点,是下一代高比能电池极具发展前景的负极.然而,锂枝晶生长和低可逆性严重阻碍了高比能锂金属电池的发展.受启发于生物细胞膜结构,本文采用涂布法在锂金属表面成功构筑了一种具有仿生离子通道的人工界面固体电解质层(CAL).该CAL中大量带负电荷的离子通道可以促进锂离子均匀、快速的输运,有利于稳定、均匀地进行锂沉积/剥离.此外,在循环过程中,CAL底部与锂金属发生原位转化反应,生成了一层富含亲锂性无机组分的过渡层,促进了锂离子的扩散并抑制了锂金属与电解液的连续副反应.因此,形成的具有双面神结构的人工界面固体电解质层(CAJL)使得锂金属负极可以在10 mA cm^(-2)的高电流密度和10 mAh cm^(-2)的高面积容量下长期稳定循环.更重要的是,基于CAJL功能化锂金属负极的锂硫软包电池实现了429.2 Wh kg^(-1)的高能量密度.
基金supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.T23-601/17-R).
文摘Redox flow batteries(RFBs)that employ sustainable,abundant,and structure-tunable redox-active species are of great interest for large-scale energy storage.As a vital class of redox-active species,metal coordination complexes(MCCs)possessing the properties of both the organic ligands and transition metal ion centers are attracting increasing attention due to the advantages of multielectron charge transfer,high structural tailorability,and reduced material crossover.Herein,we present a critical overview of RFBs that employ MCCs as redox-active materials in both aqueous and nonaqueous mediums.The progress is comprehensively summarized,including the design strategies,solubility characteristics,electrochemical properties,and battery cycling performance of MCCs.Emphasis is placed on the ligand selection and modification strategies used to tune the critical properties of MCCs,including their redox potential,solubility,cycling stability,and electron transfer redox reactions,to achieve stable cycled RFBs with a high energy density.Furthermore,we discuss the current challenges and perspectives related to the development of MCC-based RFBs for large-scale energy storage implementations.
基金supported by the National Natural Science Foundation of China(11902243 and 51903124)the Young Elite Scientist Sponsorship Program by CAST(2019QNRC001)+2 种基金the“1000-Plan Program”of Shaanxi Provincethe“Young Talent Support Plan”of Xi’an Jiaotong UniversityInitiative Funds of Scientific Research for Metasequoia Talent(163105049)。
