We proposed a strategy to address the issue by synthesizing MnO with half-filled 3 d electron orbitals.That is,MnO nanocubes with an edge length of 61.82 nm were successfully prepared through electros-pinning and one-...We proposed a strategy to address the issue by synthesizing MnO with half-filled 3 d electron orbitals.That is,MnO nanocubes with an edge length of 61.82 nm were successfully prepared through electros-pinning and one-step pyrolysis as the cathode electrode for Li-O_(2)batteries.It is observed that the intermediate LiMnO_(4)rather than Li_(2)O_(2)is formed when LiO_(2)interactes with MnO(111)during the discharge process.It is precisely because of LiMnO_(4)that reduces its charge overpotential to 0.29 V.The novel reaction mechanism dominated by LiMnO_(4)further facilitates the lower charge overpotential,thereby enhancing the energy efficiency of the batteries.展开更多
Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is s...Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is still needed.Here,the storage mechanism of Li^(+)in the tunnel structure of MnO_(2) as well as the dissolution and migration of Mn-ions were investigated based on multi-scale approaches.The Li/Mn ratio(at%)is determined at about 0.82 when the discharge voltage decreases to 2 V.The limited Li-ions transport rate in the bulk MnO_(2) restrains the reduction reaction,resulting in a low practical specific capacity.Moreover,utilizing spherical aberration-corrected transmission electron microscopy(TEM)coupled with electron energy loss spectroscopy(EELS),the presence of a mixed valence state layer of Mn^(2+)/Mn^(3+)/Mn^(4+)on the surface of the original 20 nm MnO_(2) particles was identified,which could contribute to the initial dissolution of Mn-ions.The battery separator exhibited channels for Mn-ions migration and diffusion and aggregated Mn particles.We put forward the discharge and degradation route in the ways of Mn-ions trajectories,and our findings provide a deep understanding of the high self-discharge rates and the capacity decay of Li-Mn primary batteries.展开更多
Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degra...Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degradation at high current densities.We address these issues by a“killing two birds with one stone”O_(2)-pressure protocol.It first resolves efficient O_(2) mass transport at high rates..The accelerated reaction kinetics optimizes the composition and growth pathway of discharge products.This protocol secondly achieves protection of Li anodes via densifying corrosion layers on them.Consequently,the battery delivers both ultrahigh discharge capacity(>9,000 mAh g^(-1))at 3,000 mA g^(-1) and excellent cycling stability.Under a dual-strategy effect of high-pressure O_(2) and artificial protection layers,the battery actualizes over 11-fold increase in cycle life of 5,170 h(2,585 cycles).The strategy opens avenues for advancing Li-O_(2) batteries towards practical application and confers the extension to other gas-based batteries.展开更多
Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal...Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal analyses, Fourier transformed infrared spectroscopy and high-resolution transmission electron microscopy. The results show that the sample consists of poor crystalline α-MnO2 nanorods with a diameter of about 10 nm and a length of 30-50 nm, which absorb on the carbon nanotubes. The electrochemical properties of the product as cathode material for Li-MnO2 cell are evaluated by galvanostatic charge-discharge and electrochemical impedance spectroscopy （EIS）. Compared with pure MnO2 electrode, the MnO2/CNT composite delivers a much larger initial capacity of 275.3 mA-h/g and better rate and cycling performance.展开更多
The unprecedented growth of electric vehicles featuring lithium-ion batteries has led to a significant increase in the amount of waste generated,posing pressing waste management challenges for both industry professio ...The unprecedented growth of electric vehicles featuring lithium-ion batteries has led to a significant increase in the amount of waste generated,posing pressing waste management challenges for both industry professio nals and environmental regulators.To address these issues,conventio nal pyrometallurgical,hydrometallurgical,and direct recycling methods are commonly employed to promote sustainable battery development.However,these methods are often hindered by laborious purification processes and the generation of low-profit products such as Li_(2)CO_(3),CoSO_(4),NiSO_(4),etc.Herein,an upcycling technology involving a low-temperature solid-to-solid reaction and water leaching procedures is introduced to transform spent LiCoO_(2)cathode materials into value-added cobalt sulfide-based electrocatalysts.The regenerated electrocatalysts exhibit exceptional performance in the oxygen evolution reaction,surpassing that of the benchmark RuO_(2)catalyst.This proposed upcycling method provides researchers with an alternative way to convert the metallic components of waste lithium-ion batteries into high-value Co-,Ni-,Fe-,and Mn-based catalysts.展开更多
Sodium titanium phosphate(NaTi_(2)(PO_(4))_(3),NTP)has emerged as a promising electrode material due to its three-dimensional open framework.This study investigates the use of NTP in aqueous dilute Li^(+)/Na^(+)electr...Sodium titanium phosphate(NaTi_(2)(PO_(4))_(3),NTP)has emerged as a promising electrode material due to its three-dimensional open framework.This study investigates the use of NTP in aqueous dilute Li^(+)/Na^(+)electrolytes and extends its application to high-concentration K+electrolytes.X-ray photoelectron spectroscopy,X-ray absorption near-edge structure analysis,and density functional theory calculations revealed that highly electronegative fluorine partially substitutes for oxygen in the NTP lattice,resulting in the formation of Ti-F bonds.The substitution effectively modulates the electronic structure of Ti^(4+),alters the local coordination environment,and influences the redox dynamics.Enhanced long-term cycling stability and rate performance were demonstrated across aqueous sodium-ion,lithium-ion,and potassium-ion half-cells.Among the investigated systems,the aqueous sodium-ion system exhibited the best electrochemical performance,characterized by a single,well-defined charge–discharge plateau,stable cycling behavior with 88.7%capacity retention after 500 cycles at 1 A g^(−1),and an initial specific discharge capacity of 121.7 mAh g^(−1) at 0.2 A g^(−1).The results establish F-doped NTP as a promising candidate for advanced energy storage applications in aqueous alkali metal-ion batteries.展开更多
Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life ...Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life is critical to the commercial development of AZIBs.Herein,a two-dimensional(2D) MnO/C composite derived from metal organic framework(MOF) was prepared.The 2D MnO/C cathode exhibits a remarkably cyclic stability with the capacity retention of 90.6% after 900 cycles at 0.5 A·g^(-1) and maintains a high capacity of 120.2 mAh·g^(-1)after 4500 cycles at 1.0 A·g^(-1).It is demonstrated that MnO is converted into Mn_(3)O_(4) through electrochemical activation strategy and shows a Zn^(2+)and H^(+)co-intercalation mechanism.In general,this work provides a new path for the development of high-performance AZIBs cathode with controllable morphology.展开更多
Two structure types of LiMnO 2 were synthesized by sol gel method and ion exchange method respectively.The results indicate that orthorhombic phase LiMnO 2 is more stable than layered LiMnO 2,o LiMnO 2 can be s...Two structure types of LiMnO 2 were synthesized by sol gel method and ion exchange method respectively.The results indicate that orthorhombic phase LiMnO 2 is more stable than layered LiMnO 2,o LiMnO 2 can be synthesized directly by sol gel methods followed by heat treated in argon,but layered LiMnO 2 was obtained only by indirect methods such as ion exchange method.In this paper,we first synthesized layered NaMnO 2 by the sol gel method,and then obtained layered LiMnO 2 by the ion exchange method.The phase constitution,chemical composition,and images of the products were tested by XRD,AAS (atomic absorption spectroscopy) and SEM.The electrochemical performances of the two structural types of LiMnO 2 are obviously different during the initial few cycles,but later they both have a good capacity retaining ability.The capacity of layered structure LiMnO 2 is higher than that of o LiMnO 2.展开更多
Lithium (Li) metal batteries have attracted much attention owing to its ultra-high energy density.However,as important part of Li metal batteries,Li anodes still face many challenges,mainly including uncontrolled dend...Lithium (Li) metal batteries have attracted much attention owing to its ultra-high energy density.However,as important part of Li metal batteries,Li anodes still face many challenges,mainly including uncontrolled dendritic Li formation,dramatical volume variation and serious pulverization.Herein,manganese dioxide (MnO_(2)) nanosheet modified nitrogen (N),phosphorus (P) co-doping carbon nanofibers(NPC) on carbon cloth (CC)(MnO_(2)@NPC-CC) is successfully fabricated through electrodeposition approach and further treated with Li by the molten-infusion method to prepare Li based Mn@NPC-CC(Li-Mn@NPC-CC) electrode.The synergy of MnO_(2) and NPC obviously increases the reaction rate between MnO_(2)@NPC-CC and Li and guides even Li distribution over infusion process.Additionally,theoretical calculation,simulation and experimental results further indicate that N,P,Mn multi-doping effectively improves the superior lithiophilicity of Li-Mn@NPC-CC,which induces uniform Li deposition/dissolution to suppress dendrite growth over cycles.Moreover,conductive and porous NPC matrix not only effectively improves the stability of Li-Mn@NPC-CC,but also provides abundant spaces to accelerate the transfer of ion/electron and buffer electrode dimension variation during cycling.Hence,Li-Mn@NPC-CC-based symmetric cells exhibit extra-long cycling life (over 2200 h) with small hysteresis of 20 mV.When the LiMn@NPC-CC anode couples with air,Li iron phosphate (LiFePO_(4)),or hard carbon (C) cathode,the assembled full cells exhibit outstanding performance with low hysteresis and stable cycling properties.Especially,the corresponding pouch-typed Li–air cells also exhibit good performance at different bending angles and even power a series of electronic devices.展开更多
Alkaline zinc manganese dioxide（Zn–MnO2）batteries are widely used in everyday life. Recycling of waste alkaline Zn–MnO2 batteries has always been a hot environmental concern. In this study, a simple and costeffect...Alkaline zinc manganese dioxide（Zn–MnO2）batteries are widely used in everyday life. Recycling of waste alkaline Zn–MnO2 batteries has always been a hot environmental concern. In this study, a simple and costeffective process for synthesizing Mn3O4/carbon nanotube（CNT） nanocomposites from recycled alkaline Zn–MnO2 batteries is presented. Manganese oxide was recovered from spent Zn–MnO2 battery cathodes. The Mn3O4/CNT nanocomposites were produced by ball milling the recovered manganese oxide in a commercial multi-wall carbon nanotubes（MWCNTs） solution. Scanning electron microscopy（SEM） analysis demonstrates that the nanocomposite has a unique three-dimensional（3D） bird nest structure. Mn3O4 nanoparticles are homogeneously distributed on MWCNT framework. Mn3O4/CNT nanocomposites were evaluated as an anode material for lithium-ion batteries, exhibiting a highly reversible specific capacitance of -580 mA h·g^-1 after 100 cycles. Moreover, Mn3O4/CNT nanocomposite also shows a fairly positive onset potential of -0.15 V and quite high oxygen reducibility when considered as an electrocatalyst for oxygen reduction reaction.展开更多
Nanostructured transition metal oxides,employed as anode materials for lithium-ion batteries,exhibit a higher capacity than the theoretical capacity based on the conversion reaction.To date,the reasons behind this phe...Nanostructured transition metal oxides,employed as anode materials for lithium-ion batteries,exhibit a higher capacity than the theoretical capacity based on the conversion reaction.To date,the reasons behind this phenomenon are unclear.For the one-step evolution of anode material for lithium-ion batteries,it is essential to understand the lithium storage reaction mechanism of the anode material.Herein,we provide a detailed report on the lithium storage and release mechanism of MnO2,using synchrotron-based X-ray techniques.X-ray diffraction and X-ray absorption spectroscopy results indicate that during the first discharge,MnO2 is reduced in the order of MnO2→LixMnO2(1<X<2)→MnO→Mn metal,followed by a reversible reaction between Mn metal and Mn3O4.Furthermore,soft X-ray absorption spectroscopy results indicate that additional reversible formation-decomposition of the electrolyte-derived surface layer occurs and contributes to the reversible capacity of MnO2 after the first discharge.These findings contribute to further understanding of the reaction mechanism and additional lithium storage of MnO2 and suggest practical strategies for developing high energy density anode materials for next-generation Li batteries.展开更多
Li[NixCoyMn2]O2（0.6≤x≤0.8） cathode materials with a typical hexagonal α-NaFeO2 structure were prepared utilizing a co-precipitation method.It is found that the ratio of peak intensities of（003） to（104） observ...Li[NixCoyMn2]O2（0.6≤x≤0.8） cathode materials with a typical hexagonal α-NaFeO2 structure were prepared utilizing a co-precipitation method.It is found that the ratio of peak intensities of（003） to（104） observed from X-ray diffraction（XRD）increases with decreasing the Ni content or increasing the Co content.The scanning electron microscopy（SEM） images reveal that the small primary particles are agglomerated to form the secondary ones.As the Mn content increases,the primary and secondary particles become larger and the resulted particle size for the Li[Ni（0.6）Co（0.2）Mn（0.2）]O2 is uniformly distributed in the range of100-300 nm.Although the initial discharge capacity of the Li/Li[NixCoyMn2]O2 cells reduces with decreasing the Ni content,the cyclic performance and rate capability are improved with higher Mn or Co content.The Li[Ni（0.6）Co（0.2）Mn（0.2）]O2 can deliver excellent cyclability with a capacity retention of 97.1%after 50 cycles.展开更多
Li3V2-2/3xMnx（PO4）3（0≤x≤0.12） powders were synthesized by sol-gel method. The effect of Mn2＋-doping on the structure and electrochemical performances of Li3V2（PO4）3/C was characterized by XRD, SEM, XPS, galva...Li3V2-2/3xMnx（PO4）3（0≤x≤0.12） powders were synthesized by sol-gel method. The effect of Mn2＋-doping on the structure and electrochemical performances of Li3V2（PO4）3/C was characterized by XRD, SEM, XPS, galvanostatic charge /discharge and electrochemical impedance spectroscopy（EIS）. The XRD study shows that a small amount of Mn2＋-doped does not alter the structure of Li3V2（PO4）3/C materials, and all Mn2＋-doped samples are of pure single phase with a monoclinic structure （space group P21/n）. The XPS analysis indicates that valences state of V and Mn are ＋3 and ＋2 in Li3V1.94Mn0.09（PO4）3/C, respectively, and the citric acid in raw materials was decomposed into carbon during calcination, and residual carbon exists in Li3V1.94Mn0.09（PO4）/C. The results of electrochemical measurements show that Mn2＋-doping can improve the cyclic stability and rate performance of these cathode materials. The Li3V1.94Mn0.09（PO4）3/C cathode material shows the best cyclic stability and rate performance. For example, at the discharge current density of 40 mA/g, after 100 cycles, the discharge capacity of Li3V1.94Mn0.09（PO4）3/C declines from initial 158.8 mA·h/g to 120.5 mA·h/g with a capacity retention of 75.9%; however, that of the Mn-undoed sample declines from 164.2 mA·h/g to 72.6 mA·h/g with a capacity retention of 44.2%. When the discharge current is increased up to 1C, the intial discharge capacity of Li3V1.94Mn0.09（PO4）3/C still reaches 146.4 mA·h/g, and the discharge capacity maintains at 107.5 mA·h/g after 100 cycles. The EIS measurement indicates that Mn2＋-doping with a appropriate amount of Mn2＋ decreases the charge transfer resistance, which is favorable for the insertion/extraction of Li＋.展开更多
2LiFe1-xCoxPO4-Li3V2（P04）3/C was synthesized using Fel-2xCo2xVO4 as precursor which was prepared by a simple co-precipitation method. 2LiFej-xCoxPO4-Li3V2（PO4）3/C samples were characterized by X-ray diffraction （...2LiFe1-xCoxPO4-Li3V2（P04）3/C was synthesized using Fel-2xCo2xVO4 as precursor which was prepared by a simple co-precipitation method. 2LiFej-xCoxPO4-Li3V2（PO4）3/C samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical measurements. All 2LiFel-xCoxPOa-Li3V2（PO4）3/C composites are of the similar crystal structure. The XRD analysis and SEM images show that 2LiFe0.96Co0.04PO4-Li3V2（PO4）3/C sample has the best-ordered structure and the smallest particle size. The charge-discharge tests demonstrate that these powders have the best electrochemical properties with an initial discharge capacity of 144.1 mA.h/g and capacity retention of 95.6% after 100 cycles when cycled at a current density of 0.1C between 2.5 and 4.5 V.展开更多
Aqueous rechargeable Zn/MnO2 zinc-ion batteries(ZIBs)are reviving recently due to their low cost,non-toxicity,and natural abundance.However,their energy storage mechanism remains controversial due to their complicated...Aqueous rechargeable Zn/MnO2 zinc-ion batteries(ZIBs)are reviving recently due to their low cost,non-toxicity,and natural abundance.However,their energy storage mechanism remains controversial due to their complicated electrochemical reactions.Meanwhile,to achieve satisfactory cyclic stability and rate performance of the Zn/MnO2 ZIBs,Mn2+ is introduced in the electrolyte(e.g.,ZnSO4 solution),which leads to more complicated reactions inside the ZIBs systems.Herein,based on comprehensive analysis methods including electrochemical analysis and Pourbaix diagram,we provide novel insights into the energy storage mechanism of Zn/MnO2 batteries in the presence of Mn2+.A complex series of electrochemical reactions with the coparticipation of Zn2+,H+,Mn2+,SO42-,and OH-were revealed.During the first discharge process,co-insertion of Zn2+ and H+ promotes the transformation of MnO2 into ZnxMnO4,MnOOH,and Mn2O3,accompanying with increased electrolyte pH and the formation of ZnSO4·3 Zn(OH)2-5 H2O.During the subsequent charge process,ZnxMnO4,MnOOH,and Mn2O3 revert to a-MnO2 with the extraction of Zn2+ and H+,while ZnSO4·3Zn(OH)2·5H2O reacts with Mn2+ to form ZnMn3O7·3 H2O.In the following charge/discharge processes,besides aforementioned electrochemical reactions,Zn2+ reversibly insert into/extract from α-MnO2,ZnxMnO4,and ZnMn3O7·3H2O hosts;ZnSO4·3Zn(OH)2·5 H2O,Zn2Mn3O8,and ZnMn2O4 convert mutually with the participation of Mn2+.This work is believed to provide theoretical guidance for further research on high-performance ZIBs.展开更多
A novel synthetic method of microwave processing to prepare Li2FeSiO4 cathode materials is adopted. The Li2FeSiO4 cathode material is prepared by mechanical ball-milling and subsequent microwave processing. Olivin-typ...A novel synthetic method of microwave processing to prepare Li2FeSiO4 cathode materials is adopted. The Li2FeSiO4 cathode material is prepared by mechanical ball-milling and subsequent microwave processing. Olivin-type Li2FeSiO4 sample with uniform and fine particle sizes is successfully and fast synthesized by microwave heating at 700 ℃ in 12 rain. And the obtained Li2FeSiO4 materials show better electrochemical performance and microstructure than those of Li2FeSiO4 sample by the conventional solidstate reaction. ？2009 Yan Bing Cao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.展开更多
As promising energy storage systems,lithium-sulfur(Li-S)batteries have attracted significant attention because of their ultra-high energy densities.However,Li-S battery suffers problems related to the complex phase co...As promising energy storage systems,lithium-sulfur(Li-S)batteries have attracted significant attention because of their ultra-high energy densities.However,Li-S battery suffers problems related to the complex phase conversion that occurs during the charge-discharge process,particularly the deposition of solid Li2S from the liquid-phase polysulfides,which greatly limits its practical application.In this paper,edge-rich MoS2/C hollow microspheres(Edg-MoS2/C HMs)were designed and used to functionalize separator for Li-S battery,resulting in the uniform deposition of Li2S.The microspheres were fabricated through the facile hydrothermal treatment of MoO3-aniline nanowires and a subsequent carbonization process.The obtained Edg-MoS2/C HMs have a strong chemical absorption capability and high density of Li2S binding sites,and exhibit excellent electrocatalytic performance and can effectively hinder the polysulfide shuttle effect and guide the uniform nucleation and growth of Li2S.Furthermore,we demonstrate that the Edg-MoS2/C HMs can effectively regulate the deposition of Li2S and significantly improve the reversibility of the phase conversion of the active sulfur species,especially at high sulfur loadings and high C-rates.As a result,a cell containing a separator functionalized with Edg-MoS2/C HMs exhibited an initial discharge capacity of 935 mAh g-1 at 1.0 C and maintained a capacity of 494 mAh g-1 after 1000 cycles with a sulfur loading of 1.7 mg cm-2.Impressively,at a high sulfur loading of 6.1 mg cm-2 and high rate of 0.5 C,the cell still delivered a high reversible discharge capacity of 478 mAh g-1 after 300 cycles.This work provides fresh insights into energy storage systems related to complex phase conversions.展开更多
基金Funded by the National Natural Science Foundation of China(No.22075035)the Technology Planning Project of Liaoning Province(No.2020JH2/10700008)the Dalian Science and Technology Innovation Fund Project(No.2022JJ11CG005)。
文摘We proposed a strategy to address the issue by synthesizing MnO with half-filled 3 d electron orbitals.That is,MnO nanocubes with an edge length of 61.82 nm were successfully prepared through electros-pinning and one-step pyrolysis as the cathode electrode for Li-O_(2)batteries.It is observed that the intermediate LiMnO_(4)rather than Li_(2)O_(2)is formed when LiO_(2)interactes with MnO(111)during the discharge process.It is precisely because of LiMnO_(4)that reduces its charge overpotential to 0.29 V.The novel reaction mechanism dominated by LiMnO_(4)further facilitates the lower charge overpotential,thereby enhancing the energy efficiency of the batteries.
基金supported by the National Natural Science Foundation of China(Nos.U2030206,12104022,52271014 and 22075003)the Presidential Foundation of CAEP(No.YZJJZL2023173)Sichuan Science and Technology Program(No.2021YFH0092).
文摘Li/MnO_(2) primary batteries are widely used in industry for their high specific capacity and safety.However,a deep comprehension of the Li^(+)insertion mechanism and the high self-discharge rate of the batteries is still needed.Here,the storage mechanism of Li^(+)in the tunnel structure of MnO_(2) as well as the dissolution and migration of Mn-ions were investigated based on multi-scale approaches.The Li/Mn ratio(at%)is determined at about 0.82 when the discharge voltage decreases to 2 V.The limited Li-ions transport rate in the bulk MnO_(2) restrains the reduction reaction,resulting in a low practical specific capacity.Moreover,utilizing spherical aberration-corrected transmission electron microscopy(TEM)coupled with electron energy loss spectroscopy(EELS),the presence of a mixed valence state layer of Mn^(2+)/Mn^(3+)/Mn^(4+)on the surface of the original 20 nm MnO_(2) particles was identified,which could contribute to the initial dissolution of Mn-ions.The battery separator exhibited channels for Mn-ions migration and diffusion and aggregated Mn particles.We put forward the discharge and degradation route in the ways of Mn-ions trajectories,and our findings provide a deep understanding of the high self-discharge rates and the capacity decay of Li-Mn primary batteries.
基金support from the Major basic research project of Natural Science Foundation of Shandong Province(No.ZR2023ZD12)Singapore National Research Foundation Investigatorship(No.NRFNRFI08-2022-0009)NUS R&G Postdoc Fellowship Program.
文摘Lithium-oxygen(Li-O_(2))battery is favored among“beyond lithiumion”technologies for sustainability because of its exceptional energy density.Major impediments are the poor cycle stability and grievous capacity degradation at high current densities.We address these issues by a“killing two birds with one stone”O_(2)-pressure protocol.It first resolves efficient O_(2) mass transport at high rates..The accelerated reaction kinetics optimizes the composition and growth pathway of discharge products.This protocol secondly achieves protection of Li anodes via densifying corrosion layers on them.Consequently,the battery delivers both ultrahigh discharge capacity(>9,000 mAh g^(-1))at 3,000 mA g^(-1) and excellent cycling stability.Under a dual-strategy effect of high-pressure O_(2) and artificial protection layers,the battery actualizes over 11-fold increase in cycle life of 5,170 h(2,585 cycles).The strategy opens avenues for advancing Li-O_(2) batteries towards practical application and confers the extension to other gas-based batteries.
基金Projects(21071153,20976198)supported by the National Natural Science Foundation of China
文摘Nanostructured MnO2/CNT composite was synthesized by a soft template approach in the presence of Pluronic P123 surfactant. The product was characterized by X-ray diffraction, thermogravimetric and differential thermal analyses, Fourier transformed infrared spectroscopy and high-resolution transmission electron microscopy. The results show that the sample consists of poor crystalline α-MnO2 nanorods with a diameter of about 10 nm and a length of 30-50 nm, which absorb on the carbon nanotubes. The electrochemical properties of the product as cathode material for Li-MnO2 cell are evaluated by galvanostatic charge-discharge and electrochemical impedance spectroscopy （EIS）. Compared with pure MnO2 electrode, the MnO2/CNT composite delivers a much larger initial capacity of 275.3 mA-h/g and better rate and cycling performance.
基金financial support from the National Natural Science Foundation of China(21702143,52303092)Talent Recruitment Project of Guangdong Province(No.2023QN10X078)+1 种基金Open Project of Yunnan Precious Metals Laboratory Co.,Ltd(No.YPML-2023050278)Guangdong Basic and Applied Basic Research Foundation Special Projects——GuangdongShenzhen Joint Funds(2022A1515110027)。
文摘The unprecedented growth of electric vehicles featuring lithium-ion batteries has led to a significant increase in the amount of waste generated,posing pressing waste management challenges for both industry professio nals and environmental regulators.To address these issues,conventio nal pyrometallurgical,hydrometallurgical,and direct recycling methods are commonly employed to promote sustainable battery development.However,these methods are often hindered by laborious purification processes and the generation of low-profit products such as Li_(2)CO_(3),CoSO_(4),NiSO_(4),etc.Herein,an upcycling technology involving a low-temperature solid-to-solid reaction and water leaching procedures is introduced to transform spent LiCoO_(2)cathode materials into value-added cobalt sulfide-based electrocatalysts.The regenerated electrocatalysts exhibit exceptional performance in the oxygen evolution reaction,surpassing that of the benchmark RuO_(2)catalyst.This proposed upcycling method provides researchers with an alternative way to convert the metallic components of waste lithium-ion batteries into high-value Co-,Ni-,Fe-,and Mn-based catalysts.
基金supported by the National Natural Science Foundation of China(52072298,51802261,11675129)the Natural Science Basic Research Plan in Shaanxi Province of China(2025JC-YBQN-758)+1 种基金Scientific Research Program Funded by Shaanxi Provincial Education Department(Program No.23JK0662)the Youth Innovation Team of Shaanxi Universities.
文摘Sodium titanium phosphate(NaTi_(2)(PO_(4))_(3),NTP)has emerged as a promising electrode material due to its three-dimensional open framework.This study investigates the use of NTP in aqueous dilute Li^(+)/Na^(+)electrolytes and extends its application to high-concentration K+electrolytes.X-ray photoelectron spectroscopy,X-ray absorption near-edge structure analysis,and density functional theory calculations revealed that highly electronegative fluorine partially substitutes for oxygen in the NTP lattice,resulting in the formation of Ti-F bonds.The substitution effectively modulates the electronic structure of Ti^(4+),alters the local coordination environment,and influences the redox dynamics.Enhanced long-term cycling stability and rate performance were demonstrated across aqueous sodium-ion,lithium-ion,and potassium-ion half-cells.Among the investigated systems,the aqueous sodium-ion system exhibited the best electrochemical performance,characterized by a single,well-defined charge–discharge plateau,stable cycling behavior with 88.7%capacity retention after 500 cycles at 1 A g^(−1),and an initial specific discharge capacity of 121.7 mAh g^(−1) at 0.2 A g^(−1).The results establish F-doped NTP as a promising candidate for advanced energy storage applications in aqueous alkali metal-ion batteries.
基金financially supported by the National Natural Science Foundation of China (Nos.22078200 and 51874199)Guangdong Basic and Applied Basic Research Foundation (No.2021A1515010162)。
文摘Poor conductivity,sluggish ion diffusion kinetics and short cycle life hinder the further development of manganese oxide in aqueous zinc-ion batteries(AZIBs).Exploring a cathode with high capacity and long cycle life is critical to the commercial development of AZIBs.Herein,a two-dimensional(2D) MnO/C composite derived from metal organic framework(MOF) was prepared.The 2D MnO/C cathode exhibits a remarkably cyclic stability with the capacity retention of 90.6% after 900 cycles at 0.5 A·g^(-1) and maintains a high capacity of 120.2 mAh·g^(-1)after 4500 cycles at 1.0 A·g^(-1).It is demonstrated that MnO is converted into Mn_(3)O_(4) through electrochemical activation strategy and shows a Zn^(2+)and H^(+)co-intercalation mechanism.In general,this work provides a new path for the development of high-performance AZIBs cathode with controllable morphology.
文摘Two structure types of LiMnO 2 were synthesized by sol gel method and ion exchange method respectively.The results indicate that orthorhombic phase LiMnO 2 is more stable than layered LiMnO 2,o LiMnO 2 can be synthesized directly by sol gel methods followed by heat treated in argon,but layered LiMnO 2 was obtained only by indirect methods such as ion exchange method.In this paper,we first synthesized layered NaMnO 2 by the sol gel method,and then obtained layered LiMnO 2 by the ion exchange method.The phase constitution,chemical composition,and images of the products were tested by XRD,AAS (atomic absorption spectroscopy) and SEM.The electrochemical performances of the two structural types of LiMnO 2 are obviously different during the initial few cycles,but later they both have a good capacity retaining ability.The capacity of layered structure LiMnO 2 is higher than that of o LiMnO 2.
基金funding support from the National Natural Science Foundation of China (21905151 and 51772162)the Youth Innovation and Technology Foundation of Shandong Higher Education Institutions, China (2019KJC004)+1 种基金the Outstanding Youth Foundation of Shandong Province, China (ZR2019JQ14)the Taishan Scholar Young Talent Program, Major Scientific and Technological Innovation Project (2019JZZY020405)。
文摘Lithium (Li) metal batteries have attracted much attention owing to its ultra-high energy density.However,as important part of Li metal batteries,Li anodes still face many challenges,mainly including uncontrolled dendritic Li formation,dramatical volume variation and serious pulverization.Herein,manganese dioxide (MnO_(2)) nanosheet modified nitrogen (N),phosphorus (P) co-doping carbon nanofibers(NPC) on carbon cloth (CC)(MnO_(2)@NPC-CC) is successfully fabricated through electrodeposition approach and further treated with Li by the molten-infusion method to prepare Li based Mn@NPC-CC(Li-Mn@NPC-CC) electrode.The synergy of MnO_(2) and NPC obviously increases the reaction rate between MnO_(2)@NPC-CC and Li and guides even Li distribution over infusion process.Additionally,theoretical calculation,simulation and experimental results further indicate that N,P,Mn multi-doping effectively improves the superior lithiophilicity of Li-Mn@NPC-CC,which induces uniform Li deposition/dissolution to suppress dendrite growth over cycles.Moreover,conductive and porous NPC matrix not only effectively improves the stability of Li-Mn@NPC-CC,but also provides abundant spaces to accelerate the transfer of ion/electron and buffer electrode dimension variation during cycling.Hence,Li-Mn@NPC-CC-based symmetric cells exhibit extra-long cycling life (over 2200 h) with small hysteresis of 20 mV.When the LiMn@NPC-CC anode couples with air,Li iron phosphate (LiFePO_(4)),or hard carbon (C) cathode,the assembled full cells exhibit outstanding performance with low hysteresis and stable cycling properties.Especially,the corresponding pouch-typed Li–air cells also exhibit good performance at different bending angles and even power a series of electronic devices.
基金financially supported by the National Natural Science Foundation of China(Nos.21671096 and 21603094)the Shenzhen Peacock Plan(No.KQCX2014052215 0815065)+1 种基金the Natural Science Foundation of Shenzhen(Nos.JCYJ20150630145302231 and JCYJ20150331101823677)the Science and Technology Innovation Foundation for the Undergraduates of South University of Science and Technology of China(Nos.2016S10,2016S20,2015x19 and 2015x12)
文摘Alkaline zinc manganese dioxide（Zn–MnO2）batteries are widely used in everyday life. Recycling of waste alkaline Zn–MnO2 batteries has always been a hot environmental concern. In this study, a simple and costeffective process for synthesizing Mn3O4/carbon nanotube（CNT） nanocomposites from recycled alkaline Zn–MnO2 batteries is presented. Manganese oxide was recovered from spent Zn–MnO2 battery cathodes. The Mn3O4/CNT nanocomposites were produced by ball milling the recovered manganese oxide in a commercial multi-wall carbon nanotubes（MWCNTs） solution. Scanning electron microscopy（SEM） analysis demonstrates that the nanocomposite has a unique three-dimensional（3D） bird nest structure. Mn3O4 nanoparticles are homogeneously distributed on MWCNT framework. Mn3O4/CNT nanocomposites were evaluated as an anode material for lithium-ion batteries, exhibiting a highly reversible specific capacitance of -580 mA h·g^-1 after 100 cycles. Moreover, Mn3O4/CNT nanocomposite also shows a fairly positive onset potential of -0.15 V and quite high oxygen reducibility when considered as an electrocatalyst for oxygen reduction reaction.
基金supported by the Samsung Reserach Funding & Incubation Center of Samsung Electronics under Project Number MA1401-52。
文摘Nanostructured transition metal oxides,employed as anode materials for lithium-ion batteries,exhibit a higher capacity than the theoretical capacity based on the conversion reaction.To date,the reasons behind this phenomenon are unclear.For the one-step evolution of anode material for lithium-ion batteries,it is essential to understand the lithium storage reaction mechanism of the anode material.Herein,we provide a detailed report on the lithium storage and release mechanism of MnO2,using synchrotron-based X-ray techniques.X-ray diffraction and X-ray absorption spectroscopy results indicate that during the first discharge,MnO2 is reduced in the order of MnO2→LixMnO2(1<X<2)→MnO→Mn metal,followed by a reversible reaction between Mn metal and Mn3O4.Furthermore,soft X-ray absorption spectroscopy results indicate that additional reversible formation-decomposition of the electrolyte-derived surface layer occurs and contributes to the reversible capacity of MnO2 after the first discharge.These findings contribute to further understanding of the reaction mechanism and additional lithium storage of MnO2 and suggest practical strategies for developing high energy density anode materials for next-generation Li batteries.
基金Project(21473258)supported by the National Natural Science Foundation of ChinaProject(13JJ1004)supported by the Distinguished Young Scientists of Hunan Province,ChinaProject(NCET-11-0513)supported by the New Century Excellent Talents in University,China
文摘Li[NixCoyMn2]O2（0.6≤x≤0.8） cathode materials with a typical hexagonal α-NaFeO2 structure were prepared utilizing a co-precipitation method.It is found that the ratio of peak intensities of（003） to（104） observed from X-ray diffraction（XRD）increases with decreasing the Ni content or increasing the Co content.The scanning electron microscopy（SEM） images reveal that the small primary particles are agglomerated to form the secondary ones.As the Mn content increases,the primary and secondary particles become larger and the resulted particle size for the Li[Ni（0.6）Co（0.2）Mn（0.2）]O2 is uniformly distributed in the range of100-300 nm.Although the initial discharge capacity of the Li/Li[NixCoyMn2]O2 cells reduces with decreasing the Ni content,the cyclic performance and rate capability are improved with higher Mn or Co content.The Li[Ni（0.6）Co（0.2）Mn（0.2）]O2 can deliver excellent cyclability with a capacity retention of 97.1%after 50 cycles.
基金Project (20771100) supported by the National Natural Science Foundation of China
文摘Li3V2-2/3xMnx（PO4）3（0≤x≤0.12） powders were synthesized by sol-gel method. The effect of Mn2＋-doping on the structure and electrochemical performances of Li3V2（PO4）3/C was characterized by XRD, SEM, XPS, galvanostatic charge /discharge and electrochemical impedance spectroscopy（EIS）. The XRD study shows that a small amount of Mn2＋-doped does not alter the structure of Li3V2（PO4）3/C materials, and all Mn2＋-doped samples are of pure single phase with a monoclinic structure （space group P21/n）. The XPS analysis indicates that valences state of V and Mn are ＋3 and ＋2 in Li3V1.94Mn0.09（PO4）3/C, respectively, and the citric acid in raw materials was decomposed into carbon during calcination, and residual carbon exists in Li3V1.94Mn0.09（PO4）/C. The results of electrochemical measurements show that Mn2＋-doping can improve the cyclic stability and rate performance of these cathode materials. The Li3V1.94Mn0.09（PO4）3/C cathode material shows the best cyclic stability and rate performance. For example, at the discharge current density of 40 mA/g, after 100 cycles, the discharge capacity of Li3V1.94Mn0.09（PO4）3/C declines from initial 158.8 mA·h/g to 120.5 mA·h/g with a capacity retention of 75.9%; however, that of the Mn-undoed sample declines from 164.2 mA·h/g to 72.6 mA·h/g with a capacity retention of 44.2%. When the discharge current is increased up to 1C, the intial discharge capacity of Li3V1.94Mn0.09（PO4）3/C still reaches 146.4 mA·h/g, and the discharge capacity maintains at 107.5 mA·h/g after 100 cycles. The EIS measurement indicates that Mn2＋-doping with a appropriate amount of Mn2＋ decreases the charge transfer resistance, which is favorable for the insertion/extraction of Li＋.
基金Project(51072233) supported by National Natural Science Foundation of China
文摘2LiFe1-xCoxPO4-Li3V2（P04）3/C was synthesized using Fel-2xCo2xVO4 as precursor which was prepared by a simple co-precipitation method. 2LiFej-xCoxPO4-Li3V2（PO4）3/C samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and electrochemical measurements. All 2LiFel-xCoxPOa-Li3V2（PO4）3/C composites are of the similar crystal structure. The XRD analysis and SEM images show that 2LiFe0.96Co0.04PO4-Li3V2（PO4）3/C sample has the best-ordered structure and the smallest particle size. The charge-discharge tests demonstrate that these powders have the best electrochemical properties with an initial discharge capacity of 144.1 mA.h/g and capacity retention of 95.6% after 100 cycles when cycled at a current density of 0.1C between 2.5 and 4.5 V.
基金the financial support from the International Science & Technology Cooperation Program of China (No. 2016YFE0102200)Shenzhen Technical Plan Project (No. JCYJ20160301154114273)+1 种基金National Key Basic Research(973) Program of China (No. 2014CB932400)Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program (2017BT01N111)
文摘Aqueous rechargeable Zn/MnO2 zinc-ion batteries(ZIBs)are reviving recently due to their low cost,non-toxicity,and natural abundance.However,their energy storage mechanism remains controversial due to their complicated electrochemical reactions.Meanwhile,to achieve satisfactory cyclic stability and rate performance of the Zn/MnO2 ZIBs,Mn2+ is introduced in the electrolyte(e.g.,ZnSO4 solution),which leads to more complicated reactions inside the ZIBs systems.Herein,based on comprehensive analysis methods including electrochemical analysis and Pourbaix diagram,we provide novel insights into the energy storage mechanism of Zn/MnO2 batteries in the presence of Mn2+.A complex series of electrochemical reactions with the coparticipation of Zn2+,H+,Mn2+,SO42-,and OH-were revealed.During the first discharge process,co-insertion of Zn2+ and H+ promotes the transformation of MnO2 into ZnxMnO4,MnOOH,and Mn2O3,accompanying with increased electrolyte pH and the formation of ZnSO4·3 Zn(OH)2-5 H2O.During the subsequent charge process,ZnxMnO4,MnOOH,and Mn2O3 revert to a-MnO2 with the extraction of Zn2+ and H+,while ZnSO4·3Zn(OH)2·5H2O reacts with Mn2+ to form ZnMn3O7·3 H2O.In the following charge/discharge processes,besides aforementioned electrochemical reactions,Zn2+ reversibly insert into/extract from α-MnO2,ZnxMnO4,and ZnMn3O7·3H2O hosts;ZnSO4·3Zn(OH)2·5 H2O,Zn2Mn3O8,and ZnMn2O4 convert mutually with the participation of Mn2+.This work is believed to provide theoretical guidance for further research on high-performance ZIBs.
基金supported by National Key Technology R&D Program of China(No.2007BAE12B01-1)Science and Technology Planning Program of Hunan Province,China(No.2008GK3015)
文摘A novel synthetic method of microwave processing to prepare Li2FeSiO4 cathode materials is adopted. The Li2FeSiO4 cathode material is prepared by mechanical ball-milling and subsequent microwave processing. Olivin-type Li2FeSiO4 sample with uniform and fine particle sizes is successfully and fast synthesized by microwave heating at 700 ℃ in 12 rain. And the obtained Li2FeSiO4 materials show better electrochemical performance and microstructure than those of Li2FeSiO4 sample by the conventional solidstate reaction. ？2009 Yan Bing Cao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.
基金financially supported by National Natural Science Foundation of China (No. 51672083)Program of Shanghai Academic/Technology Research Leader (18XD1401400)+3 种基金Basic Research Program of Shanghai (17JC1404702)Leading talents in Shanghai in 2018The 111 project (B14018)the Fundamental Research Funds for the Central Universities (222201718002)
文摘As promising energy storage systems,lithium-sulfur(Li-S)batteries have attracted significant attention because of their ultra-high energy densities.However,Li-S battery suffers problems related to the complex phase conversion that occurs during the charge-discharge process,particularly the deposition of solid Li2S from the liquid-phase polysulfides,which greatly limits its practical application.In this paper,edge-rich MoS2/C hollow microspheres(Edg-MoS2/C HMs)were designed and used to functionalize separator for Li-S battery,resulting in the uniform deposition of Li2S.The microspheres were fabricated through the facile hydrothermal treatment of MoO3-aniline nanowires and a subsequent carbonization process.The obtained Edg-MoS2/C HMs have a strong chemical absorption capability and high density of Li2S binding sites,and exhibit excellent electrocatalytic performance and can effectively hinder the polysulfide shuttle effect and guide the uniform nucleation and growth of Li2S.Furthermore,we demonstrate that the Edg-MoS2/C HMs can effectively regulate the deposition of Li2S and significantly improve the reversibility of the phase conversion of the active sulfur species,especially at high sulfur loadings and high C-rates.As a result,a cell containing a separator functionalized with Edg-MoS2/C HMs exhibited an initial discharge capacity of 935 mAh g-1 at 1.0 C and maintained a capacity of 494 mAh g-1 after 1000 cycles with a sulfur loading of 1.7 mg cm-2.Impressively,at a high sulfur loading of 6.1 mg cm-2 and high rate of 0.5 C,the cell still delivered a high reversible discharge capacity of 478 mAh g-1 after 300 cycles.This work provides fresh insights into energy storage systems related to complex phase conversions.
