The urgent demand for clean energy solutions has intensified the search for advanced storage materials,with rechargeable alkali-ion batteries(AIBs)playing a pivotal role in electrochemical energy storage.Enhancing ele...The urgent demand for clean energy solutions has intensified the search for advanced storage materials,with rechargeable alkali-ion batteries(AIBs)playing a pivotal role in electrochemical energy storage.Enhancing electrode performance is critical to addressing the increasing need for high-energy and high-power AIBs.Next-generation anode materials face significant challenges,including limited energy storage capacities and complex reaction mechanisms that complicate structural modeling.Sn-based materials have emerged as promising candidates for AIBs due to their inherent advantages.Recent research has increasingly focused on the development of heterojunctions as a strategy to enhance the performance of Sn-based anode materials.Despite significant advances in this field,comprehensive reviews summarizing the latest developments are still sparse.This review provides a detailed overview of recent progress in Sn-based heterojunction-type anode materials.It begins with an explanation of the concept of heterojunctions,including their fabrication,characterization,and classification.Cutting-edge research on Sn-based heterojunction-type anodes for AIBs is highlighted.Finally,the review summarizes the latest advancements in heterojunction technology and discusses future directions for research and development in this area.展开更多
High-performance lithium-ion batteries and sodium-ion batteries have been developed utilizing a hybrid anode material composed of zinc sulfide/sulfurized polyacrylonitrile.The in situ-generated zinc sulfide nanopartic...High-performance lithium-ion batteries and sodium-ion batteries have been developed utilizing a hybrid anode material composed of zinc sulfide/sulfurized polyacrylonitrile.The in situ-generated zinc sulfide nanoparticles serve as catalytic agents,significantly enhancing conductivity,shortening diffusion paths,and accelerating reaction kinetics.Simultaneously,the sulfurized polyacrylonitrile fibers form a three-dimensional matrix that not only provides a continuous network for rapid electron transfer but also prevents zinc sulfide nanoparticle aggregation and mitigates volume changes during charge-discharge cycles.Moreover,the heterointerface structure at the junction of zinc sulfide nanoparticles and the sulfurized polyacrylonitrile matrix increases the availability of active sites and facilitates both ion adsorption and electron transfer.As an anode material for lithium-ion batteries,the zinc sulfide/sulfurized polyacrylonitrile hybrid demonstrates a high reversible capacity of 1178 mAh g^(-1)after 100 cycles at a current density of 0.2 A g^(-1),maintaining a capacity of 788 mAh g^(-1)after 200 cycles at 1 A g^(-1).It also exhibits excellent sodium storage capabilities,retaining a capacity of 625 mAh g^(-1)after 150 cycles at 0.2 A g^(-1).Furthermore,ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,7Li solid-state magic angle spinning nuclear magnetic resonance,and in situ Raman are employed to investigate the reaction mechanisms of the zinc sulfide/sulfurized polyacrylonitrile hybrid anode,providing valuable insights that pave the way for the advancement of hybrid anode materials in lithium-ion batteries and sodium-ion batteries.展开更多
The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contribut...The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of LIBs.Herein,we try to review the recent reports on the synthesis and characterizations of low-temperature anode materials.First,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero temperatures.Second,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are presented.Third,several commonly used low-temperature anode materials are briefly introduced.Fourth,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase materials.Finally,the challenges that remain to be solved in the field of low-temperature anode materials are discussed.This review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance.展开更多
Magnesium-ion batteries(MIBs)are promising candidates for lithium-ion batteries because of their abundance,non-toxicity,and favorable electrochemical properties.This review explores the reaction mechanisms and electro...Magnesium-ion batteries(MIBs)are promising candidates for lithium-ion batteries because of their abundance,non-toxicity,and favorable electrochemical properties.This review explores the reaction mechanisms and electrochemical characteristics of Mg-alloy anode materials.While Mg metal anodes provide high volumetric capacity and dendrite-free electrodeposition,their practical application is hindered by challenges such as sluggish Mg^(2+)ion diffusion and electrolyte compatibility.Alloy-type anodes that incorporate groups XIII,XIV,and XV elements have the potential to overcome these limitations.We review various Mg alloys,emphasizing their alloying/dealloying reaction mechanisms,their theoretical capacities,and the practical aspects of MIBs.Furthermore,we discuss the influence of the electrolyte composition on the reversibility and efficiency of these alloy anodes.Emphasis is placed on overcoming current limitations through innovative materials and structural engineering.This review concludes with perspectives on future research directions aimed at enhancing the performance and commercial viability of Mg alloy anodes and contributing to the development of high-capacity,safe,and cost-effective energy storage systems.展开更多
Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage systems.The development of ultralow voltage anode materials is of great significance in...Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage systems.The development of ultralow voltage anode materials is of great significance in improving the energy density of NIBs.Low-voltage anode materials,however,are severely lacking in NIBs.Of all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V vs.Na^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high safety.Although significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe challenge.This paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further elaborated.Finally,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are highlighted.This review offers insights into the design of high-energy and high-safety NIBs.展开更多
Sodium-ion batteries are promising candidates for large-scale grid storage systems and other applications.Their foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw m...Sodium-ion batteries are promising candidates for large-scale grid storage systems and other applications.Their foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion batteries.It is still challenging to explore desirable anode material.In this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and selenisation.The FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the heterostructure.Moreover,it delivers high performance(510 mAh g^(-1)at 0.2 A g^(-1)),superior rate capa-bility(90%retention at 5 A g^(-1)),and good long-time cycling stability(78%capacity retention after 1800 cycles at a high current density of 2 A g^(-1)).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent performance.Namely,a ca-pacity of 272 mAh g^(-1)(at 1 A g^(-1))within the operating voltage from 1 to 3.8 V can be obtained.This work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.展开更多
There is an ideal desire to develop the high-performance anodes materials for Liion batteries(LIBs),which requires not onlyhigh stability and reversibility,but also rapidcharging/discharging rate.In this work,webuilta...There is an ideal desire to develop the high-performance anodes materials for Liion batteries(LIBs),which requires not onlyhigh stability and reversibility,but also rapidcharging/discharging rate.In this work,webuiltablue phosphorene-graphene(BlueP-G)intralayer heterostructure by connecting BlueP and graphene monolayers at zigzag edges with covalent bonds.Based on the density functional theory simulation,the electronic structure of the heterostructure,Li adsorption and Li diffusion on heterostructure were systematically investigated.Compared with the pristine BlueP,the existence of graphene layer increases the overall conductivity of BlueP-G intralayer heterostructure.The significantly enhanced adsorption energy indicates the Li deposition on anode surface is energetically favored.The fast diffusion of Li with energy barrier as low as 0.02-0.09 eV indicates the growth of Li dendrite could be suppressed and the stability and reversibility of the battery will be increased.With a combination of increased conductivity of electronic charge,excellent Li adsorption and Li mobility on surface,BlueP-G intralayer heterostructure with zigzag interface is quite promising in the application of anode material for Li-ion batteries.展开更多
Iron oxide(Fe_(2)O_(3))emerges as a highly attractive anode candidate among rapidly expanding energy storage market.Nonethe-less,its considerable volume changes during cycling as an electrode material result in a vast...Iron oxide(Fe_(2)O_(3))emerges as a highly attractive anode candidate among rapidly expanding energy storage market.Nonethe-less,its considerable volume changes during cycling as an electrode material result in a vast reduced battery cycle life.In this work,an ap-proach is pioneered for preparing high-performance Fe_(2)O_(3)anode materials,by innovatively synthesizing a triple-layer yolk-shell Fe_(2)O_(3)uniformly coated with a conductive polypyrrole(Ppy)layer(Fe_(2)O_(3)@Ppy-TLY).The uniform polypyrrole coating introduces more reac-tion sites and adsorption sites,and maintains structure stability through charge-discharge process.In the uses as lithium-ion battery elec-trodes,Fe_(2)O_(3)@Ppy-TLY demonstrates high reversible specific capacity(maintaining a discharge capacity of 1375.11 mAh·g^(−1)after 500 cycles at 1 C),exceptional cycling stability(retaining the steady charge-discharge performance at 544.33 mAh·g^(−1)after 6000 ultrafast charge-discharge cycles at a 10 C current density),and outstanding high current charge-discharge performance(retaining a reversible ca-pacity of 156.75 mAh·g^(−1)after 10000 cycles at 15 C),thereby exhibiting superior lithium storage performance.This work introduces in-novative advancements for Fe_(2)O_(3)anode design,aiming to enhance its performance in energy storage fields.展开更多
A facile way was used to synthesize Cu2O/reduced graphene oxide （rGO） composites with octahedron-like morphology in aqueous solution without any surfactant. TEM images of the obtained Cu2O/rGOs reveal that the Cu2O ...A facile way was used to synthesize Cu2O/reduced graphene oxide （rGO） composites with octahedron-like morphology in aqueous solution without any surfactant. TEM images of the obtained Cu2O/rGOs reveal that the Cu2O particles and rGO distribute hierarchically and the primary Cu2O particles are encapsulated well in the graphene nanosheets. The electrochemical performance of Cu2O/rGOs is enhanced compared with bare Cu2O when they are employed as anode materials for lithium ion batteries. The Cu2O/rGO composites maintain a reversible capacity of 348.4 mA？h/g after 50 cycles at a current density of 100 mA/g. In addition, the composites retain 305.8 mA？h/g after 60 cycles at various current densities of 50, 100, 200, 400 and 800 mA/g.展开更多
Since lithium-ion batteries(LIBs) have been substantially researched in recent years, they now possess exceptional energy and power densities, making them the most suited energy storage technology for use in developed...Since lithium-ion batteries(LIBs) have been substantially researched in recent years, they now possess exceptional energy and power densities, making them the most suited energy storage technology for use in developed and developing industries like stationary storage and electric cars, etc. Concerns about the cost and availability of lithium have prompted research into alternatives, such as sodium-ion batteries(SIBs), which use sodium instead of lithium as the charge carrier. This is especially relevant for stationary applications, where the size and weight of battery are less important. The working efficiency and capacity of these batteries are mainly dependent on the anode, cathode, and electrolyte. The anode,which is one of these components, is by far the most important part of the rechargeable battery.Because of its characteristics and its structure, the anode has a tremendous impact on the overall performance of the battery as a whole. Keeping the above in view, in this review we critically reviewed the different types of anodes and their performances studied to date in LIBs and SIBs. The review article is divided into three main sections, namely:(i) intercalation reaction-based anode materials;(ii) alloying reaction-based anode materials;and(iii) conversion reaction-based anode materials, which are further classified into a number of subsections based on the type of material used. In each main section, we have discussed the merits and challenges faced by their particular system. Afterward, a brief summary of the review has been discussed. Finally, the road ahead for better application of Li/Na-ion batteries is discussed, which seems to mainly depend on exploring the innovative materials as anode and on the inoperando characterization of the existing materials for making them more capable in terms of application in rechargeable batteries.展开更多
The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of ...The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of LIBs rely directly on the electrode materials.As far as the development of the advanced LIBs electrode is concerned,the improvement of anode materials is more urgent than the cathode materials.Industrial production of anode materials superior to commercial graphite still faces some challenges.This review sets out the most basic LIBs anode material design.The reaction principles and structural design of carbon materials,various transition metal oxides,silicon and germanium are summarized,and then the progress of other anode materials are analyzed.Due to the rapid development of metal organic frameworks(MOFs)in energy storage and conversion in recent years,the synthesis process and energy storage mechanism of nanostructures derived from MOF precursors are also discussed.From the perspective of novel structural design,the progress of various MOFs-derived materials for alleviating the volume expansion of anode materials is discussed.Finally,challenges for the future development of advanced anode materials for LIBs will be considered.展开更多
Aluminum is an innovative anode material for seawater battery. But large polarization and low electrochemical activity restrict its application. In this research, A1-Mg-Sn-Hg-Ce anode materials were prepared and the m...Aluminum is an innovative anode material for seawater battery. But large polarization and low electrochemical activity restrict its application. In this research, A1-Mg-Sn-Hg-Ce anode materials were prepared and the microstructures were investigated by scanning electron microscopy （SEM）. The electrochemical properties of A1-Mg-Sn-Hg-Ce anode materials were measured by potentiodynamic polarization and potential-time discharge in a 4.5 wt.%NaOH solution at 353 K. The results indicated that the increasing content of cerium addition refined the grain structure of A1-Mg-Sn-Hg alloy and promoted the uniform distribution of Sn and Hg elements in A1 matrix. The morphology of second phases changed from disperse granular to intergranulate strip with the increasing content of cerium addition in AI-Mg-Sn-Hg alloy. During the half-cell tests at a 650 mA/cm3 current density, the discharge activity of AI-Mg-Sn-Hg-Ce alloy was improved with the increasing content of cerium addition. The average discharge potential of AI-Mg-Sn-Hg-0.3 wt.%Ce alloy was -1.721 V （vs. SCE）, which was more negative than -1.406 V （vs. SCE） in AZglD. The best corrosion resistance occurred in A1-Mg-Sn-Hg-0.05 wt.%Ce alloy with the corrosion current density, 18.84± 2.21 mA/cm2. The corrosion behaviours of A1-Mg-Sn-Hg-Ce alloys were also analyzed.展开更多
Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To pr...Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.展开更多
Micro-sized（1030.3±178.4 nm） and nano-sized（50.4±8.0 nm） Fe3O4 particles have been fabricated through hydrogen thermal reduction of α-Fe2O3 particles synthesized by means of a hydrothermal process.The m...Micro-sized（1030.3±178.4 nm） and nano-sized（50.4±8.0 nm） Fe3O4 particles have been fabricated through hydrogen thermal reduction of α-Fe2O3 particles synthesized by means of a hydrothermal process.The morphology and microstructure of the micro-sized and the nano-sized Fe3O4 particles were characterized by X-ray diffraction,field-emission gun scanning electron microscopy,transmission electron microscopy and highresolution electron microscopy.The micro-sized Fe3O4 particles exhibit porous structure,while the nano-sized Fe3O4 particles are solid structure.Their electrochemical performance was also evaluated.The nano-sized solid Fe3O4 particles exhibit gradual capacity fading with initial discharge capacity of 1083.1 mAhg-1 and reversible capacity retention of 32.6% over 50 cycles.Interestingly,the micro-sized porous Fe3O4 particles display very stable capacity-cycling behavior,with initial discharge capacity of 887.5 mAhg-1 and charge capacity of 684.4 mAhg-1 at the 50th cycle.Therefore,77.1% of the reversible capacity can be maintained over 50 cycles.The micro-sized porous Fe3O4 particles with facile synthesis,good cycling performance and high capacity retention are promising candidate as anode materials for high energy-density lithium-ion batteries.展开更多
Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-...Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-Sb-Cu nanoparticles have a specific hollow structure with a uniform particle size of 10-20 nm.As there are not any hard templates in the synthesis system,a galvanic displacement reaction mechanism is proposed to account for the formation of the hollow nanostructures.When the alloy powders are used as anode materials for lithium-ion batteries,they exhibit relatively high electrochemical capacity and good cyclic retention.The good electrochemical performance can be attributed to the inactive Cu species.During electrochemical reactions,the inactive copper phase in the hollow structure serves as a soft and ductile matrix,which alleviates the mechanical stresses caused by the severe volume change during lithium insertion and extraction.With their high reversible capacities,the Sn-Sb-Cu alloys are a promising candidate as the anode material of rechargeable lithium-ion batteries.展开更多
Bismuth (Bi) has indeed inspired great interests in lithium-ion batteries (LIBs) due to the high capacity,but was still limited by the low electrical conductivity and large volume variation.Herein,a composite material...Bismuth (Bi) has indeed inspired great interests in lithium-ion batteries (LIBs) due to the high capacity,but was still limited by the low electrical conductivity and large volume variation.Herein,a composite material based on Bi nanoparticles in situ encapsulated by carbon film (Bi@CF) is prepared successfully through a facile metal–organic framework (MOF)-engaged approach.As anode materials for LIBs,the Bi@CF composites achieved high reversible capacities of 705 and 538 mAh g^(-1)at 0.2 and 0.5 A g^(-1) after200 cycles,and long cycling performance with a stable capacity of 306 mAh g^(-1)at 1.0 A g^(-1) even after 900 cycles.In situ X-ray diffraction (XRD) measurements clearly revealed the conversion between Bi and Li_(3)Bi during the alloying/dealloying process,confirming the good electrochemical reversibility of Bi@CF for Li-storage.The reaction kinetics of this Bi@CF composite was further studied by galvanostatic intermittent titration technique (GITT).This work may provide an inspiration for the elaborate design and facile preparation of alloy-type anode materials for high-performance rechargeable batteries.展开更多
In recent years,there has been significant growth in the demand for secondary batteries,and researchers are increasingly taking an interest in the development of nextgeneration battery systems.Magnesium-ion batteries(...In recent years,there has been significant growth in the demand for secondary batteries,and researchers are increasingly taking an interest in the development of nextgeneration battery systems.Magnesium-ion batteries(MIBs)have been recognized as the optimal alternative to lithium-ion batteries(LIBs)due to their low cost,superior safety,and environment-friendliness.However,research and development on rechargeable MIBs are still underway as some serious problems need to be resolved.One of the most serious obstacles is the generation of an irreversible passivation layer on the surface of the Mg anode during cycling.In addition to exploring new electrolytes for MIBs,alternative anode materials for MIBs might be an effective solution to this issue.In this review,the composition and working principle of MIBs have been discussed.In addition,recent advances in the area of anode materials(metals and their alloys,metal oxides,and two-dimensional materials)available for MIBs and the corresponding Mg-storage mechanisms have also been summarized.Further,feasible strategies,including structural design,dimension reduction,and introduction of the second phase,have been employed to design high-performance MIB anodes.展开更多
Co Fe2O4-graphene nanosheets(Co Fe2O4-GNSs) were synthesized through an ultrasonic method, and their electrochemical performances as Li-ion battery electrode were improved by annealing processes. The nanocomposites ob...Co Fe2O4-graphene nanosheets(Co Fe2O4-GNSs) were synthesized through an ultrasonic method, and their electrochemical performances as Li-ion battery electrode were improved by annealing processes. The nanocomposites obtained at 350 °C maintained a high specific capacity of 1,257 m Ah g-1even after 200 cycles at 0.1 A g-1. Furthermore,the obtained materials also have better rate capability, and it can be maintained to 696, 495, 308, and 254 m Ah g-1at 1, 2,5, and 10 A g-1, respectively. The enhancements realized in the reversible capacity and cyclic stability can be attributed to the good improvement in the electrical conductivity achieved by annealing at appropriate temperature, and the electrochemical nature of Co Fe2O4 and GNSs during discharge–charge processes.展开更多
A novel porous silicon was synthesized through a magnesiothermic reduction method of molecular sieve for the first time, Si/C composite was synthesized by using pitch as carbon source. The porous Si/C composite shows ...A novel porous silicon was synthesized through a magnesiothermic reduction method of molecular sieve for the first time, Si/C composite was synthesized by using pitch as carbon source. The porous Si/C composite shows a high initial specific capacity of 2018.5 mAh/g with current density of 0.1 A/g. When the current density increases to 2 A/g, it still exhibits high average specific capacity of 640.3 mAh/g. The porous structure can remit the Si particle pulverization during the lithiation]delithiation process. This article can provide a reference for the research of the porous Si anode for the high performance rechargeable lithium-ion battery.展开更多
Two low-cost synthesis routes have been developed to fabricate carbon-coated Li4Ti5O12 by using H2TiO3 instead of anatase TiO2 as Ti source through solid-state reaction process. One route is a direct solid mixture of ...Two low-cost synthesis routes have been developed to fabricate carbon-coated Li4Ti5O12 by using H2TiO3 instead of anatase TiO2 as Ti source through solid-state reaction process. One route is a direct solid mixture of H2TiO3, Li2CO3 and pitch followed by high-temperature solid-state reaction. The other includes mixture of H2TiO3 and Li2CO3 with pitch dissolved in furanidine under vacuum and the same solid-state reaction procedure is followed after the mixture is totally dried. Microstructural investigations indicate that H2TiO3 exhibits secondary aggregates morphology with primary particle sizes of 10-20 nm. Carbon-coating layers with thickness of 2-3 nm have been observed on Li4Ti5O12 synthesized by the two routes. Cyclic performance, rate capability and electrochemical impedance spectrum of the two Li4Ti5O12/C composites have been performed, which indicate that Li4Ti5O12/C obtained by furanidine-assisted mixture exhibits better electrochemical performance than Li4Ti5O12/C synthesized by direct solid mixture. The possible reasons have been discussed. The low-cost synthesis routes of Li4Ti5O12/C using H2TiO3 as Ti source are expected to be more competitive than the traditional one for practical applications.展开更多
文摘The urgent demand for clean energy solutions has intensified the search for advanced storage materials,with rechargeable alkali-ion batteries(AIBs)playing a pivotal role in electrochemical energy storage.Enhancing electrode performance is critical to addressing the increasing need for high-energy and high-power AIBs.Next-generation anode materials face significant challenges,including limited energy storage capacities and complex reaction mechanisms that complicate structural modeling.Sn-based materials have emerged as promising candidates for AIBs due to their inherent advantages.Recent research has increasingly focused on the development of heterojunctions as a strategy to enhance the performance of Sn-based anode materials.Despite significant advances in this field,comprehensive reviews summarizing the latest developments are still sparse.This review provides a detailed overview of recent progress in Sn-based heterojunction-type anode materials.It begins with an explanation of the concept of heterojunctions,including their fabrication,characterization,and classification.Cutting-edge research on Sn-based heterojunction-type anodes for AIBs is highlighted.Finally,the review summarizes the latest advancements in heterojunction technology and discusses future directions for research and development in this area.
基金supported by“regional innovation mega project”program through the Korea Innovation Foundation funded by Ministry of Science and ICT(Project Number:2023-DD-UP-0026)the Energy Technology Evaluation and Planning(KETEP)and the Ministry of Trade,Industry&Energy(MOTIE)(No.RS-2024-00509401,RS-2023-00217581)“Regional Innovation Strategy(RIS)”through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(MOE)(2021RIS-001).
文摘High-performance lithium-ion batteries and sodium-ion batteries have been developed utilizing a hybrid anode material composed of zinc sulfide/sulfurized polyacrylonitrile.The in situ-generated zinc sulfide nanoparticles serve as catalytic agents,significantly enhancing conductivity,shortening diffusion paths,and accelerating reaction kinetics.Simultaneously,the sulfurized polyacrylonitrile fibers form a three-dimensional matrix that not only provides a continuous network for rapid electron transfer but also prevents zinc sulfide nanoparticle aggregation and mitigates volume changes during charge-discharge cycles.Moreover,the heterointerface structure at the junction of zinc sulfide nanoparticles and the sulfurized polyacrylonitrile matrix increases the availability of active sites and facilitates both ion adsorption and electron transfer.As an anode material for lithium-ion batteries,the zinc sulfide/sulfurized polyacrylonitrile hybrid demonstrates a high reversible capacity of 1178 mAh g^(-1)after 100 cycles at a current density of 0.2 A g^(-1),maintaining a capacity of 788 mAh g^(-1)after 200 cycles at 1 A g^(-1).It also exhibits excellent sodium storage capabilities,retaining a capacity of 625 mAh g^(-1)after 150 cycles at 0.2 A g^(-1).Furthermore,ex-situ X-ray photoelectron spectroscopy,X-ray diffraction,7Li solid-state magic angle spinning nuclear magnetic resonance,and in situ Raman are employed to investigate the reaction mechanisms of the zinc sulfide/sulfurized polyacrylonitrile hybrid anode,providing valuable insights that pave the way for the advancement of hybrid anode materials in lithium-ion batteries and sodium-ion batteries.
基金supported by the National Key Research and Development Program of China(No.2019YFA0705601)the National Natural Science Foundation of China(No.U23A20122,52101267)the Key Science and Technology Special Project of Henan Province(No.201111311400).
文摘The severe degradation of electrochemical performance for lithium-ion batteries(LIBs)at low temperatures poses a significant challenge to their practical applications.Consequently,extensive efforts have been contributed to explore novel anode materials with high electronic conductivity and rapid Li^(+)diffusion kinetics for achieving favorable low-temperature performance of LIBs.Herein,we try to review the recent reports on the synthesis and characterizations of low-temperature anode materials.First,we summarize the underlying mechanisms responsible for the performance degradation of anode materials at subzero temperatures.Second,detailed discussions concerning the key pathways(boosting electronic conductivity,enhancing Li^(+)diffusion kinetics,and inhibiting lithium dendrite)for improving the low-temperature performance of anode materials are presented.Third,several commonly used low-temperature anode materials are briefly introduced.Fourth,recent progress in the engineering of these low-temperature anode materials is summarized in terms of structural design,morphology control,surface&interface modifications,and multiphase materials.Finally,the challenges that remain to be solved in the field of low-temperature anode materials are discussed.This review was organized to offer valuable insights and guidance for next-generation LIBs with excellent low-temperature electrochemical performance.
基金supported by the Global Joint Research Program funded by the Pukyong National University(202411790001).
文摘Magnesium-ion batteries(MIBs)are promising candidates for lithium-ion batteries because of their abundance,non-toxicity,and favorable electrochemical properties.This review explores the reaction mechanisms and electrochemical characteristics of Mg-alloy anode materials.While Mg metal anodes provide high volumetric capacity and dendrite-free electrodeposition,their practical application is hindered by challenges such as sluggish Mg^(2+)ion diffusion and electrolyte compatibility.Alloy-type anodes that incorporate groups XIII,XIV,and XV elements have the potential to overcome these limitations.We review various Mg alloys,emphasizing their alloying/dealloying reaction mechanisms,their theoretical capacities,and the practical aspects of MIBs.Furthermore,we discuss the influence of the electrolyte composition on the reversibility and efficiency of these alloy anodes.Emphasis is placed on overcoming current limitations through innovative materials and structural engineering.This review concludes with perspectives on future research directions aimed at enhancing the performance and commercial viability of Mg alloy anodes and contributing to the development of high-capacity,safe,and cost-effective energy storage systems.
基金supported by the National Natural Science Foundation of China (52307239,52102300,52207234)the Natural Science Foundation of Hubei Province (2022CFB1003,2021CFA025)。
文摘Due to its low cost and natural abundance of sodium,Na-ion batteries(NIBs)are promising candidates for large-scale energy storage systems.The development of ultralow voltage anode materials is of great significance in improving the energy density of NIBs.Low-voltage anode materials,however,are severely lacking in NIBs.Of all the reported insertion oxides anodes,the Na_(2)Ti_(3)O_(7) has the lowest operating voltage(an average potential of 0.3 V vs.Na^(+)/Na)and is less likely to deposit sodium,which has excellent potential for achieving NIBs with high energy densities and high safety.Although significant progress has been made,achieving Na_(2)Ti_(3)O_(7) electrodes with excellent performance remains a severe challenge.This paper systematically summarizes and discusses the physicochemical properties and synthesis methods of Na_(2)Ti_(3)O_(7).Then,the sodium storage mechanisms,key issues and challenges,and the optimization strategies for the electrochemical performance of Na_(2)Ti_(3)O_(7) are classified and further elaborated.Finally,remaining challenges and future research directions on the Na_(2)Ti_(3)O_(7) anode are highlighted.This review offers insights into the design of high-energy and high-safety NIBs.
基金supported by the National Natural Science Foundation of China(Nos.21801200 and 22075217)the Open Project of Hunan Key Laboratory of Applied Environmental Photocatalysis(No.2114504)the Natural Science Foundation of Hubei Province of China(No.2022CFA001).
文摘Sodium-ion batteries are promising candidates for large-scale grid storage systems and other applications.Their foremost advantage derives from superior environmental credentials,enhanced safety as well as lower raw material costs than lithium-ion batteries.It is still challenging to explore desirable anode material.In this study,FeSe_(2)@CoSe_(2)/FeSe_(2),with a yolk-shell structure was prepared by ion exchange and selenisation.The FeSe_(2)@CoSe_(2)/FeSe_(2)prepared as anode material for sodiumion batteries exhibits excellent rate capability due to the synergistic effect of bimetallic selenides and the interfacial effect of the heterostructure.Moreover,it delivers high performance(510 mAh g^(-1)at 0.2 A g^(-1)),superior rate capa-bility(90%retention at 5 A g^(-1)),and good long-time cycling stability(78%capacity retention after 1800 cycles at a high current density of 2 A g^(-1)).The optimized sodiumion full cell with FeSe_(2)@CoSe_(2)/FeSe_(2)as the anode and Na 3 V 2(PO 4)3 as the cathode still demonstrates excellent performance.Namely,a ca-pacity of 272 mAh g^(-1)(at 1 A g^(-1))within the operating voltage from 1 to 3.8 V can be obtained.This work illustrates the potential of bimetallic selenides with heterostructures for performance enhancement of sodium-ion batteries.
基金This work was supported by the National Natural Science Foundation of China(No.21825302 and No.21903076)the Taishan Scholar Program of Shandong Province of China(tsqn201909122)We also thank Supercomputing Center of USTC(USTC-SCC),Supercomputing Center of the Chinese Academy of Sciences(SCCAS),Tianjin Supercomputer Center,Guangzhou Supercomputer Center,and the Shanghai Supercomputer Center.
文摘There is an ideal desire to develop the high-performance anodes materials for Liion batteries(LIBs),which requires not onlyhigh stability and reversibility,but also rapidcharging/discharging rate.In this work,webuiltablue phosphorene-graphene(BlueP-G)intralayer heterostructure by connecting BlueP and graphene monolayers at zigzag edges with covalent bonds.Based on the density functional theory simulation,the electronic structure of the heterostructure,Li adsorption and Li diffusion on heterostructure were systematically investigated.Compared with the pristine BlueP,the existence of graphene layer increases the overall conductivity of BlueP-G intralayer heterostructure.The significantly enhanced adsorption energy indicates the Li deposition on anode surface is energetically favored.The fast diffusion of Li with energy barrier as low as 0.02-0.09 eV indicates the growth of Li dendrite could be suppressed and the stability and reversibility of the battery will be increased.With a combination of increased conductivity of electronic charge,excellent Li adsorption and Li mobility on surface,BlueP-G intralayer heterostructure with zigzag interface is quite promising in the application of anode material for Li-ion batteries.
基金supported by the Natural Science Foundation of Jiangsu Province of China(No.BK20201008).
文摘Iron oxide(Fe_(2)O_(3))emerges as a highly attractive anode candidate among rapidly expanding energy storage market.Nonethe-less,its considerable volume changes during cycling as an electrode material result in a vast reduced battery cycle life.In this work,an ap-proach is pioneered for preparing high-performance Fe_(2)O_(3)anode materials,by innovatively synthesizing a triple-layer yolk-shell Fe_(2)O_(3)uniformly coated with a conductive polypyrrole(Ppy)layer(Fe_(2)O_(3)@Ppy-TLY).The uniform polypyrrole coating introduces more reac-tion sites and adsorption sites,and maintains structure stability through charge-discharge process.In the uses as lithium-ion battery elec-trodes,Fe_(2)O_(3)@Ppy-TLY demonstrates high reversible specific capacity(maintaining a discharge capacity of 1375.11 mAh·g^(−1)after 500 cycles at 1 C),exceptional cycling stability(retaining the steady charge-discharge performance at 544.33 mAh·g^(−1)after 6000 ultrafast charge-discharge cycles at a 10 C current density),and outstanding high current charge-discharge performance(retaining a reversible ca-pacity of 156.75 mAh·g^(−1)after 10000 cycles at 15 C),thereby exhibiting superior lithium storage performance.This work introduces in-novative advancements for Fe_(2)O_(3)anode design,aiming to enhance its performance in energy storage fields.
基金Project (2014CB643406) supported by the National Basic Research Program of ChinaProject (2011FJ1005) supported by Major Special Project of Science and Technology of Hunan Province,China
文摘A facile way was used to synthesize Cu2O/reduced graphene oxide （rGO） composites with octahedron-like morphology in aqueous solution without any surfactant. TEM images of the obtained Cu2O/rGOs reveal that the Cu2O particles and rGO distribute hierarchically and the primary Cu2O particles are encapsulated well in the graphene nanosheets. The electrochemical performance of Cu2O/rGOs is enhanced compared with bare Cu2O when they are employed as anode materials for lithium ion batteries. The Cu2O/rGO composites maintain a reversible capacity of 348.4 mA？h/g after 50 cycles at a current density of 100 mA/g. In addition, the composites retain 305.8 mA？h/g after 60 cycles at various current densities of 50, 100, 200, 400 and 800 mA/g.
文摘Since lithium-ion batteries(LIBs) have been substantially researched in recent years, they now possess exceptional energy and power densities, making them the most suited energy storage technology for use in developed and developing industries like stationary storage and electric cars, etc. Concerns about the cost and availability of lithium have prompted research into alternatives, such as sodium-ion batteries(SIBs), which use sodium instead of lithium as the charge carrier. This is especially relevant for stationary applications, where the size and weight of battery are less important. The working efficiency and capacity of these batteries are mainly dependent on the anode, cathode, and electrolyte. The anode,which is one of these components, is by far the most important part of the rechargeable battery.Because of its characteristics and its structure, the anode has a tremendous impact on the overall performance of the battery as a whole. Keeping the above in view, in this review we critically reviewed the different types of anodes and their performances studied to date in LIBs and SIBs. The review article is divided into three main sections, namely:(i) intercalation reaction-based anode materials;(ii) alloying reaction-based anode materials;and(iii) conversion reaction-based anode materials, which are further classified into a number of subsections based on the type of material used. In each main section, we have discussed the merits and challenges faced by their particular system. Afterward, a brief summary of the review has been discussed. Finally, the road ahead for better application of Li/Na-ion batteries is discussed, which seems to mainly depend on exploring the innovative materials as anode and on the inoperando characterization of the existing materials for making them more capable in terms of application in rechargeable batteries.
基金financial support from the National Natural Science Foundation of China(81671737)the support from‘Sponsored by Shanghai Pujiang Program’(18PJD020)the Interdisciplinary Program of Shanghai Jiao Tong University(YG2019QNB31)。
文摘The rapid development of electric vehicles and mobile electronic devices is the main driving force to improve advanced high-performance lithium ion batteries(LIBs).The capacity,rate performance and cycle stability of LIBs rely directly on the electrode materials.As far as the development of the advanced LIBs electrode is concerned,the improvement of anode materials is more urgent than the cathode materials.Industrial production of anode materials superior to commercial graphite still faces some challenges.This review sets out the most basic LIBs anode material design.The reaction principles and structural design of carbon materials,various transition metal oxides,silicon and germanium are summarized,and then the progress of other anode materials are analyzed.Due to the rapid development of metal organic frameworks(MOFs)in energy storage and conversion in recent years,the synthesis process and energy storage mechanism of nanostructures derived from MOF precursors are also discussed.From the perspective of novel structural design,the progress of various MOFs-derived materials for alleviating the volume expansion of anode materials is discussed.Finally,challenges for the future development of advanced anode materials for LIBs will be considered.
基金supported by National Natural Science Foundation of China(51101171)the Specialized Research Fund for the Doctor Program of Higher Education(20110162120051)
文摘Aluminum is an innovative anode material for seawater battery. But large polarization and low electrochemical activity restrict its application. In this research, A1-Mg-Sn-Hg-Ce anode materials were prepared and the microstructures were investigated by scanning electron microscopy （SEM）. The electrochemical properties of A1-Mg-Sn-Hg-Ce anode materials were measured by potentiodynamic polarization and potential-time discharge in a 4.5 wt.%NaOH solution at 353 K. The results indicated that the increasing content of cerium addition refined the grain structure of A1-Mg-Sn-Hg alloy and promoted the uniform distribution of Sn and Hg elements in A1 matrix. The morphology of second phases changed from disperse granular to intergranulate strip with the increasing content of cerium addition in AI-Mg-Sn-Hg alloy. During the half-cell tests at a 650 mA/cm3 current density, the discharge activity of AI-Mg-Sn-Hg-Ce alloy was improved with the increasing content of cerium addition. The average discharge potential of AI-Mg-Sn-Hg-0.3 wt.%Ce alloy was -1.721 V （vs. SCE）, which was more negative than -1.406 V （vs. SCE） in AZglD. The best corrosion resistance occurred in A1-Mg-Sn-Hg-0.05 wt.%Ce alloy with the corrosion current density, 18.84± 2.21 mA/cm2. The corrosion behaviours of A1-Mg-Sn-Hg-Ce alloys were also analyzed.
基金the financial support from the National Natural Science Foundation of China(No.91963118)the 111 Project(No.B13013)supported by the Open Project Program of Key Laboratory of Preparation and Application of Environmental Friendly Materials(Jilin Normal University),Ministry of Education,China(No.2020004)。
文摘Graphite as a promising anode candidate of K-ion batteries(KIBs)has been increasingly studied currently,but corresponding rate performance and cycling stability are usually inferior to amorphous carbon materials.To protect the layer structure and further boost performance,tempura-like carbon/carbon nanocomposite of graphite@pitch-derived S-doped carbon(G@PSC)is designed and prepared by a facile and low-temperature modified molten salt method.This robust encapsulation structure makes their respective advantages complementary to each other,showing mutual promotion of electrochemical performances caused by synergy effect.As a result,the G@PSC electrode is applied in KIBs,delivering impressive rate capabilities(465,408,370,332,290,and 227 m A h g^(-1)at 0.05,0.2,0.5,1,2,and 5 A g^(-1))and ultralong cyclic stability(163 m A g^(-1)remaining even after 8000 cycles at 2 A g^(-1)).On basis of ex-situ studies,the sectionalized K-storage mechanism with adsorption(pseudocapacitance caused by S doping)-intercalation(pitch-derived carbon and graphite)pattern is revealed.Moreover,the exact insights into remarkable rate performances are taken by electrochemical kinetics tests and density functional theory calculation.In a word,this study adopts a facile method to synthesize high-performance carbon/carbon nanocomposite and is of practical significance for development of carbonaceous anode in KIBs.
基金supported by the National Natural Science Foundation of China (Grand No. 50872032)the financial support from the Hundred Talents Program of the Chinese Academy of Sciencesthe National Basic Research Program of China(Grant No. 2010CB631006)
文摘Micro-sized（1030.3±178.4 nm） and nano-sized（50.4±8.0 nm） Fe3O4 particles have been fabricated through hydrogen thermal reduction of α-Fe2O3 particles synthesized by means of a hydrothermal process.The morphology and microstructure of the micro-sized and the nano-sized Fe3O4 particles were characterized by X-ray diffraction,field-emission gun scanning electron microscopy,transmission electron microscopy and highresolution electron microscopy.The micro-sized Fe3O4 particles exhibit porous structure,while the nano-sized Fe3O4 particles are solid structure.Their electrochemical performance was also evaluated.The nano-sized solid Fe3O4 particles exhibit gradual capacity fading with initial discharge capacity of 1083.1 mAhg-1 and reversible capacity retention of 32.6% over 50 cycles.Interestingly,the micro-sized porous Fe3O4 particles display very stable capacity-cycling behavior,with initial discharge capacity of 887.5 mAhg-1 and charge capacity of 684.4 mAhg-1 at the 50th cycle.Therefore,77.1% of the reversible capacity can be maintained over 50 cycles.The micro-sized porous Fe3O4 particles with facile synthesis,good cycling performance and high capacity retention are promising candidate as anode materials for high energy-density lithium-ion batteries.
基金financially supported by the National Natural Science Foundation of China(No.51202014)。
文摘Ternary Sn-Sb-Cu alloy nanoparticles were successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution.The results of the transmission electron microscopy(TEM)show that the as prepared Sn-Sb-Cu nanoparticles have a specific hollow structure with a uniform particle size of 10-20 nm.As there are not any hard templates in the synthesis system,a galvanic displacement reaction mechanism is proposed to account for the formation of the hollow nanostructures.When the alloy powders are used as anode materials for lithium-ion batteries,they exhibit relatively high electrochemical capacity and good cyclic retention.The good electrochemical performance can be attributed to the inactive Cu species.During electrochemical reactions,the inactive copper phase in the hollow structure serves as a soft and ductile matrix,which alleviates the mechanical stresses caused by the severe volume change during lithium insertion and extraction.With their high reversible capacities,the Sn-Sb-Cu alloys are a promising candidate as the anode material of rechargeable lithium-ion batteries.
基金supported by the 100 Talents Plan Foundation of Sun Yat-sen UniversityThousand Youth Talents Plan of China and Guangdong Province+1 种基金the Program for Guangdong Introducing Innovative and Entrepreneurial Teams (2017ZT07C069)the NSFC Projects (22075321, 21821003 and 21890380)。
文摘Bismuth (Bi) has indeed inspired great interests in lithium-ion batteries (LIBs) due to the high capacity,but was still limited by the low electrical conductivity and large volume variation.Herein,a composite material based on Bi nanoparticles in situ encapsulated by carbon film (Bi@CF) is prepared successfully through a facile metal–organic framework (MOF)-engaged approach.As anode materials for LIBs,the Bi@CF composites achieved high reversible capacities of 705 and 538 mAh g^(-1)at 0.2 and 0.5 A g^(-1) after200 cycles,and long cycling performance with a stable capacity of 306 mAh g^(-1)at 1.0 A g^(-1) even after 900 cycles.In situ X-ray diffraction (XRD) measurements clearly revealed the conversion between Bi and Li_(3)Bi during the alloying/dealloying process,confirming the good electrochemical reversibility of Bi@CF for Li-storage.The reaction kinetics of this Bi@CF composite was further studied by galvanostatic intermittent titration technique (GITT).This work may provide an inspiration for the elaborate design and facile preparation of alloy-type anode materials for high-performance rechargeable batteries.
基金the Graduate Research and Innovation Foundation of Chongqing,China(Grant No.CYS19034)the Fundamental Research Funds for the Central Universities(No.2019CDJGFCL001)the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJZD-K201800101)。
文摘In recent years,there has been significant growth in the demand for secondary batteries,and researchers are increasingly taking an interest in the development of nextgeneration battery systems.Magnesium-ion batteries(MIBs)have been recognized as the optimal alternative to lithium-ion batteries(LIBs)due to their low cost,superior safety,and environment-friendliness.However,research and development on rechargeable MIBs are still underway as some serious problems need to be resolved.One of the most serious obstacles is the generation of an irreversible passivation layer on the surface of the Mg anode during cycling.In addition to exploring new electrolytes for MIBs,alternative anode materials for MIBs might be an effective solution to this issue.In this review,the composition and working principle of MIBs have been discussed.In addition,recent advances in the area of anode materials(metals and their alloys,metal oxides,and two-dimensional materials)available for MIBs and the corresponding Mg-storage mechanisms have also been summarized.Further,feasible strategies,including structural design,dimension reduction,and introduction of the second phase,have been employed to design high-performance MIB anodes.
基金supported by the Program of National Natural Science Foundation of China (21071097, 20901050)National Basic Research Program of China (2014CB239700)+1 种基金Shanghai Nano-Project (12 nm0503502)Minhang District Developing Project
文摘Co Fe2O4-graphene nanosheets(Co Fe2O4-GNSs) were synthesized through an ultrasonic method, and their electrochemical performances as Li-ion battery electrode were improved by annealing processes. The nanocomposites obtained at 350 °C maintained a high specific capacity of 1,257 m Ah g-1even after 200 cycles at 0.1 A g-1. Furthermore,the obtained materials also have better rate capability, and it can be maintained to 696, 495, 308, and 254 m Ah g-1at 1, 2,5, and 10 A g-1, respectively. The enhancements realized in the reversible capacity and cyclic stability can be attributed to the good improvement in the electrical conductivity achieved by annealing at appropriate temperature, and the electrochemical nature of Co Fe2O4 and GNSs during discharge–charge processes.
基金supported by "the Fundamental Research Funds for the Central Universities" (Nos.53200859564 and 53200859035)
文摘A novel porous silicon was synthesized through a magnesiothermic reduction method of molecular sieve for the first time, Si/C composite was synthesized by using pitch as carbon source. The porous Si/C composite shows a high initial specific capacity of 2018.5 mAh/g with current density of 0.1 A/g. When the current density increases to 2 A/g, it still exhibits high average specific capacity of 640.3 mAh/g. The porous structure can remit the Si particle pulverization during the lithiation]delithiation process. This article can provide a reference for the research of the porous Si anode for the high performance rechargeable lithium-ion battery.
基金supported by the National Natural Science Foundation of China (No.50872032)
文摘Two low-cost synthesis routes have been developed to fabricate carbon-coated Li4Ti5O12 by using H2TiO3 instead of anatase TiO2 as Ti source through solid-state reaction process. One route is a direct solid mixture of H2TiO3, Li2CO3 and pitch followed by high-temperature solid-state reaction. The other includes mixture of H2TiO3 and Li2CO3 with pitch dissolved in furanidine under vacuum and the same solid-state reaction procedure is followed after the mixture is totally dried. Microstructural investigations indicate that H2TiO3 exhibits secondary aggregates morphology with primary particle sizes of 10-20 nm. Carbon-coating layers with thickness of 2-3 nm have been observed on Li4Ti5O12 synthesized by the two routes. Cyclic performance, rate capability and electrochemical impedance spectrum of the two Li4Ti5O12/C composites have been performed, which indicate that Li4Ti5O12/C obtained by furanidine-assisted mixture exhibits better electrochemical performance than Li4Ti5O12/C synthesized by direct solid mixture. The possible reasons have been discussed. The low-cost synthesis routes of Li4Ti5O12/C using H2TiO3 as Ti source are expected to be more competitive than the traditional one for practical applications.
