In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadin...In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadings.Here,we propose a novel separator structure with an interlayer composed of a vermiculite nanosheet combined with Ketjen Black(VMT@KB)for LSBs,facilitating efficient adsorption and rapid catalytic conversion toward lithium polysulfides(LiPSs).The VMT@KB nanosheets with an electrical double-layer structure and electronic conductivity are obtained through a high-temperature peeling process and Li^(+)exchange treatment in LiCl solution,followed by a mechanical combination process with KB.The results demonstrate that incorporating VMT@KB as an interlayer on a conventional separator enhances the conductivity and limits the LiPSs in the cathode region.The Li-S cell with VMT@KB interlayer shows satisfactory cycle and rate performance,especially in high sulfur loading.It exhibits a remarkable initial discharge capacity of 1225 mAh g^(-1)at 0.5 C and maintains a capacity of 816 mAh g^(-1)after 500 cycles.Besides,the discharge capacity remains 462 mAh g^(-1)even at 6 C.Moreover,the cell with high sulfur loading(8.2 mg cm^(-2))enables stable cycling for 100 cycles at 0.1 C with a discharge capacity of over1000 mAh g^(-1).展开更多
Owing to the advantages of high energy density,low cost,abundant sulfur reserves and environmentally friendly nature,lithium-sulfur batteries(LSBs)were considered as one of the potential candidates of energy storage d...Owing to the advantages of high energy density,low cost,abundant sulfur reserves and environmentally friendly nature,lithium-sulfur batteries(LSBs)were considered as one of the potential candidates of energy storage devices for the next generation.However,the significant challenges in this area stem from the sluggish reaction kinetics of the insoluble Li_(2)S product and the capacity degradation triggered by the severe shuttle effect of polysulfides.It has been firmly established through numerous studies that modifying separators is an effective approach to enhance the properties of LSBs by facilitating the catalytic kinetic conversion and chemical adsorption of lithium polysulfides(Li PSs).In this work,we report a straightforward method for fabrication of the phosphorus doped porous CeO_(2)(P-CeO_(2))as separator modifier to accelerate the catalytic kinetic conversion of polysulfides and effectively inhibit the shuttle effect in LSBs.Through coin batteries tests,P-CeO_(2)modified PP separator(P-CeO_(2)//PP)exhibits remarkable electrochemical performance.It demonstrates a high initial capacity of 1180 mAh/g at 0.5 C,surpassing the performance of the bare CeO_(2)//PP separator.Furthermore,the P-CeO_(2)//PP separator demonstrates enhanced cycling stability,with a low-capacity fading rate of only 0.048%per cycle over 1000 cycles at 2 C.In compared with bare CeO_(2)//PP,P-CeO_(2)//PP exhibits high redox peak current,enhanced adsorption property of Li_(2)S_(6)and early Li_(2)S precipitation.These results highlight the superior performance of the P-CeO_(2)//PP separator compared to the bare CeO_(2)//PP separator.Hence,this research presents a successful strategy for the modification of LIBs separator with improved electrochemical performance and cycle stability.展开更多
The intrinsic clustering behavior and kinetically sluggish conversion process of lithium polysulfides seriously limit the electrochemical reversibility of sulfur redox reactions in lithium-sulfur(Li-S)batteries.Here,w...The intrinsic clustering behavior and kinetically sluggish conversion process of lithium polysulfides seriously limit the electrochemical reversibility of sulfur redox reactions in lithium-sulfur(Li-S)batteries.Here,we introduce molybdenum pentachloride(MoCl_(5))into the electrolyte which could coordinate with lithium polysulfides and inhibit their intrinsic clustering behavior,subsequently serving as an improved mediator with the bi-functional catalytic effect for Li_(2)S deposition and activation.Moreover,the coordination bonding and accelerated conversion reaction can also greatly suppress the dissolution and shuttling of polysulfides.Consequently,such polysulfide complexes enable the Li-S coin cell to exhibit good longterm cycling stability with a capacity decay of 0.078%per cycle after 400 cycles at 2 C,and excellent rate performance with a discharge capacity of 589 mAh/g at 4 C.An area capacity of 3.94 mAh/cm^(2)is also achieved with a high sulfur loading of 4.5mg/cm^(2)at 0.2 C.Even at-20℃,the modified cell maintains standard discharge plateaus with low overpotential,delivering a high capacity of 741 mAh/g at 0.2 C after 80 cycles.The low-cost and convenient MoCl_(5)additive opens a new avenue for the effective regulation of polysulfides and significant enhancement in sulfur redox conversion.展开更多
Developing electrocatalysts to inhibit polysulfide shuttling and expedite sulfur species conversion is vital for the evolution of Lithium-sulfur(Li-S)batteries.This work provides a facile strategy to design an intimat...Developing electrocatalysts to inhibit polysulfide shuttling and expedite sulfur species conversion is vital for the evolution of Lithium-sulfur(Li-S)batteries.This work provides a facile strategy to design an intimate heterostructure of MIL-88A@CdS as a sulfur electrocatalyst combining high sulfur adsorption and accelerated polysulfide conversion.The MIL-88A can give a region of high-ordered polysulfide adsorption,whereas the CdS is an effective nanoreactor for the sulfur reduction reaction(SRR).Notedly,the significant size difference between MIL-88A and CdS enables the unique heterostructure interactions.The largesize MIL-88A ensures a uniform distribution of CdS nanoparticles as a substrate.This configuration facilitates control of the initial polysulfide adsorption position relative to its final deposition site as lithium sulfide.The heterostructure also demonstrates rapid transport and efficient conversion of lithium polysulfides.Consequently,the Li-S battery with MIL-88A@CdS heterostructure modified separator delivers exceptional performance,achieving an areal capacity exceeding 6 mAh cm^(−2),an excellent rate capability of 980 mAh g^(−1) at 5 C,and notable cycling stability in a 2 Ah pouch cell over 100 cycles.This work is significant for elucidating the relationship between heterostructure and electrocatalytic performance,providing great insights for material design aimed at highly efficient future electrocatalysts in practical applications.展开更多
Lithium-sulfur batteries are considered to be a new generation of high energy density batteries due to their non-toxicity,low cost and high theoretical specific capacity.However,the development of practical lithium-su...Lithium-sulfur batteries are considered to be a new generation of high energy density batteries due to their non-toxicity,low cost and high theoretical specific capacity.However,the development of practical lithium-sulfur batteries is seriously impeded by the sluggish multi-electron redox reaction of sulfur species and obstinate shuttle effect of polysulfides.In this study,a porous lanthanum oxychloride(LaOCl)nanofiber is designed as adsorbent and electrocatalyst of polysulfides to regulate the redox kinetics and suppress shuttling of sulfur species.Benefiting from the porous architecture and luxuriant active site of LaOCl nanofibers,the meliorative polarization effect and sulfur expansion can be accomplished.The LaOCl/S electrode exhibits an initial discharge specific capacity of 1112.3 mAh/g at 0.1 C and maintains a superior cycling performance with a slight decay of 0.02%per cycle over 1000 cycles at 1.0 C.Furthermore,even under a high sulfur loading of 4.6mg/cm^(2),the S cathode with LaOCl nanofibers still retains a high reversible areal capacity of 4.2 mAh/cm^(2)at 0.2 C and a stable cycling performance.Such a porous host expands the application of rare earth based catalysts in lithium-sulfur batteries and provides an alternative approach to facilitate the polysulfides conversion kinetics.展开更多
Lithium-sulfur(Li-S)batteries with high energy density suffer from the soluble lithium polysulfide species,Traditional metal sulfides containing a single metal element used as electrocatalysts for Li-S batteries commo...Lithium-sulfur(Li-S)batteries with high energy density suffer from the soluble lithium polysulfide species,Traditional metal sulfides containing a single metal element used as electrocatalysts for Li-S batteries commonly have limited catalytic abilities to improve battery performance.Herein,based on the Hume-Rothery rule and solvothermal method,the high-entropy sulfide NiCoCuTiVS_(x)derived from Co_(9)S_(8)was designed and synthesized,to realize the combination of small local strain and excellent catalytic performance.With all five metal elements(Ni,Co,Cu,Ti,and V)capable of chemical interactions with soluble polysulfides,NiCoCuTiVS_(x)exhibited strong chemical confinement of polysulfides and promoted fast kinetics for polysulfides conversion.Consequently,the S/NiCoCuTiVS_(x)cathode can maintain a high discharge capacity of 968.9 mA h g^(-1)after 200 cycles at 0.5 C and its capacity retention is 1.3 times higher than that of S/Co_(9)S_(8).The improved cycle stability can be attributed to the synergistic effect originating from the multiple metal elements,coupled with the reduced nucleation and activation barriers of Li_(2)S.The present work opens a path to explore novel electrocatalyst materials based on high entropy materials for the achievement of advanced Li-S batteries.展开更多
Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effe...Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effect of polysulfides and the growth of lithium dendrites greatly hinder their further development and commercial application.In this paper,cobalt-molybdenum bimetallic carbides heterostructure(Co_(6)Mo_(6)C_(2)@Co@NC)was successfully prepared through chemical etching procedure of ZIF-67 precursor with sodium molybdate and the subsequent high temperature annealing process.The obtained dodecahedral Co_(6)Mo_(6)C_(2)@Co@NC with hollow and porous structure provides large specific surface area and plentiful active sites,which speeds up the chemisorption and catalytic conversion of polysulfides,thus mitigating the shuttle effect of polysulfides and the generation of lithium dendrites.When applied as the LSBs separator modifier layer,the cell with modified separator present excellent rate capability and durable cycling stability.In particular,the cell with Co_(6)Mo_(6)C_(2)@Co@NC/PP separator can maintain the high capacity of 738 mAh/g at the current density of 2 C and the specific capacity of 782.6 mAh/g after 300 cycles at 0.5 C,with the coulombic efficiency(CE)near to 100%.Moreover,the Co_(6)Mo_(6)C_(2)@Co@NC/PP battery exhibits the impressive capacity of 431 mAh/g in high sulfur loading(4.096 mg/cm^(2))at 0.5 C after 200 cycles.This work paves the way for the development of bimetallic carbides heterostructure multifunctional catalysts for durable Li-S battery applications and reveals the synergistic regulation of polysulfides and lithium dendrites through the optimization of the structure and composition.展开更多
Metal phosphosulfides(MPS_(x)),especially BiPS_(4),have emerged as promising anode candidates for sodiumion batteries,distinguished by distinctive multinary redox chemistry,open tunnel-type structure,and high theoreti...Metal phosphosulfides(MPS_(x)),especially BiPS_(4),have emerged as promising anode candidates for sodiumion batteries,distinguished by distinctive multinary redox chemistry,open tunnel-type structure,and high theoretical capacity(>1000 m Ah g^(-1)).However,their practical implementation is fundamentally limited by polysulfide dissolution/shuttling and structural instability during prolonged cycling.Herein,we develop a groundbreaking two-stage metal-organic framework(MOF)-engineered compositing strategy through which Bi-MOF-derived BiPS_(4)/C pillars are robustly armored with conductive Ni-HHTP(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene)nanorods.Density functional theory calculations reveal that this design achieves dual functionality:increased carrier density for enhanced charge transport dynamics and effective polysulfide adsorption to inhibit dissolution.The fabricated BiPS_(4)/C@Ni-HHTP composite delivers remarkable electrochemical properties,including high initial charge/discharge specific capacities of 1063.6/1181.3 mAh g^(-1)at 0.1 A g^(-1)and outstanding long-term stability with 99.2% capacity retention after 2000 cycles at 2 A g^(-1).Such superb performance stems from the perfect synergy of the inherent high-capacity redox behavior of BiPS_(4),the buffering effect of MOF-derived carbon,and the conductivity,adsorption sites and mechanical resilience of Ni-HHTP.This work establishes a new design paradigm for MPS_(x)materials,demonstrating how to simultaneously overcome conductivity limitations and shuttle effects in conversion-type electrodes.展开更多
The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxome...The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxometalate(POM)nanoclusters with high catalytic activity and cobalt selenide with strong polarity are initially complemented to construct a PMo_(12)/CoSe_(2)@NC/CNTs multifunctional separator that can simultaneously solve the above problems.A series of experimental and theoretical results demonstrate that the Keggin-type POM,H_(3)PMo_(12)O_(40)nH_(2)O(PMo_(12))nanoclusters could function as catalytic centers for sulfur-involved transformations,with the CoSe_(2)nanoparticles serving as adsorption sites for soluble polysulfides.Accordingly,the assembled battery with the PMo_(12)/CoSe_(2)@NC/CNTs modified separator achieves an initial discharge capacity of 1263.79 mA h g^(-1),maintaining 635.77 mA h g^(-1),with a capacity decay rate of 0.06%per cycle after 500 cycles at 3C.This work provides a strategic approach for incorporating POM nanoclusters with polar periodic nanomaterials in LSB separators,contributing to the development of multifunctional separator materials,thus promoting the advancement of energy storage systems.展开更多
Developing effective heterostructure strategies to mitigate the shuttling effect and accelerate lithium polysulfide(Li PS)conversion remains a critical challenge in lithium–sulfur(Li–S)batteries.Here,we report the f...Developing effective heterostructure strategies to mitigate the shuttling effect and accelerate lithium polysulfide(Li PS)conversion remains a critical challenge in lithium–sulfur(Li–S)batteries.Here,we report the first carbon–free VO_(2)–VS_(2)heterostructure material synthesized via in situ sulfurization,applied as a modifier on a commercial polypropylene(PP)separator(denoted as VO_(2)–VS_(2)@PP).The as–prepared VO_(2)–VS_(2)nanorods synergistically combine the high absorptivity of VO_(2)with the efficient catalytic properties of VS_(2),simultaneously enhancing Li PS anchoring and promoting its conversion.We systematically investigate the influence of material composition on battery performance,leveraging these functional attributes,Li–S cells incorporating VO_(2)–VS_(2)@PP exhibit exceptional cycle stability(over 500cycles at 1C),impressive rate performance(807 m Ah.g^(–1)at 5C),desirable reversibility(49.9%capacity retention after 300 cycles at 5C)and exceptional pouch cell performance(3.65 m Ah.cm^(–2)after 50 stable cycles at 0.1C).This study underscores the potential of tailored heterostructures in realizing high–performance Li–S batteries,offering new insights for next–generation energy storage solutions.展开更多
Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a ...Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a great challenge for their commercial application.In contrast,soft sulfur-based materials feature better interface contact and chemical compatibility.Herein,an interfacial compatible polysulfide Ti_(4)P_(8)S_(29) with robust Ti-S bonding and a highly active P-S unit is tailored as a high-performance cathode for SPSBs.The Ti_(4)P_(8)S_(29) cathode possesses a three-dimensional channel structure for offering ample Na+diffusion pathways.The assembled poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)-based SPSBs deliver a discharge capacity of 136 mAh·g^(-1)at 0.5C after 200 cycles.Furthermore,a discharge capacity of 88 mAh·g^(-1)is retained after 600 cycles at a high rate of 2C,surpassing many cathode materials in SPSBs.A dual-site redox of Ti^(4+)/Ti^(3+)and S^(-)/S^(2-)is verified by X-ray photoelectron spectroscopy(XPS)and cyclic voltammetry(CV)tests.Interestingly,a refined locally-ordered amorphous structure is unveiled by in situ and ex situ characterizations.The as-formed electrode structure with lots of open channels and isotropic properties are more beneficial for ion diffusion on the interface of electrode and solid-state polymer electrolytes(SPEs),leading to faster Na+diffusion kinetics.This work proposes a strategy of modulating open-channel to boost conversion kinetics in polysulfide cathode and opens a new pathway for designing high-performance SPSBs.展开更多
Lithium-sulfur(Li-S)batteries promise high energy density but suffer from low conductivity,polysulfide shuttling,and sluggish conversion kinetics.The construction of heterointerfaces is an effective strategy for enhan...Lithium-sulfur(Li-S)batteries promise high energy density but suffer from low conductivity,polysulfide shuttling,and sluggish conversion kinetics.The construction of heterointerfaces is an effective strategy for enhancing both polysulfide adsorption and conversion;however,the poor lattice compatibility in the heterointerface formed by different materials hinders interfacial charge transfer.In response to these challenges,herein,a biphasic homojunction of TiO_(2)enriched with oxygen vacancies and decorated with nitrogen-doped carbon nanotubes(B-TiO_(2-x)@NCNT)was designed to simultaneously enhance adsorption ability and catalytic activity.This homojunction interface composed of rutile(110)and anatase(101)plane exhibits excellent compatibility,and density functional theory(DFT)calculations reveal that this biphasic interface possesses a much higher binding energy to polysulfides compared to single-phase TiO_(2).Additionally,NCNTs are in situ grown on both interior and exterior surfaces of the hollow TiO_(2)nanospheres,facilitating rapid electron transfer for the encapsulated sulfur.The homojunction interface synergistically leverages the oxygen vacancies and highly conductive NCNTs to enhance the bidirectional catalytic activity for polysulfide conversion.Therefore,in this multifunctional sulfur-host,polysulfides are first strongly adsorbed at the homojunction interfaces and subsequently undergo smooth conversion,nucleation,and decomposition,completing a rapid sulfur redox cycle.The assembled Li-S battery delivered a high specific capacity of 1234.3 mAh g^(-1)at 0.2 C,long cycling stability for over 1000 cycles at 5 C with a low decay rate of 0.035%,and exciting areal capacity at a high sulfur loading of 5.6 mg cm^(-2)for 200cycles.展开更多
Lithium-sulfur batteries(LSBs)have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density,low...Lithium-sulfur batteries(LSBs)have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density,low cost,and environmental friendliness.However,the development and commercialization path of LSBs still presents significant limitations and challenges,particularly the notorious shuttle effect triggered by soluble longchain lithium polysulfides(LiPSs),which inevitably leads to low utilization of cathode active sulfur and high battery capacity degradation,short cycle life,etc.Substantial research efforts have been conducted to develop various sulfur host materials capable of effectively restricting the shuttle effect.This review firstly introduces the fundamental electrochemical aspects of LSBs,followed by a comprehensive analysis of the mechanism underlying the shuttle effect in Li–S batteries and its profound influence on various battery components as well as the overall battery performance.Subsequently,recent advances and strategies are systematically reviewed,including physical confinement,chemisorption,and catalytic conversion of sulfur hosts for restricting LiPSs shuttle effects.The interplay mechanisms of sulfur hosts and LiPSs are discussed in detail and the structural advantages of different host materials are highlighted.Furthermore,key insights for the rational design of advanced host materials for LSBs are provided,and the upcoming challenges and the prospects for sulfur host materials in lithium-sulfur batteries are also explored.展开更多
Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)ca...Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)cathode enhances the kinetics of the redox processes of the insulating sulfu r,which also arouses the notorious shuttle effect,leading to serious loss of S species and corrosion of Li anode.To get a balance between the shuttle restraining and the kinetic property,a combined strategy of electrolyte regulation and cathode modification is proposed via introducing 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoroprpyl ether(HFE)instead of 1,2-dimethoxyethane(DME),and SeS_(7)instead of S_8.The introduction of HFE tunes the solvation structure of the LiTFSI and the dissolution of intermediate polysulfides with Se doping(LiPSSes),and optimize the interface stability of the Li anode simultaneously.The minor Se substitution compensates the decrease in kinetic due to the decreased solubility of LiPSs.In this way,the Li-SeS_(7)batteries deliver a reversible capacity of 1062 and 1037 mAh g^(-1)with 2.0 and 5.5 mg SeS_(7)cm^(-2)loading condition,respectively.Besides,an electrolyte-electrode loading model is established to explain the relationship between the optimal electrolyte and cathode loading.It makes more sense to guide the electrolyte design for practical Li-S batteries.展开更多
Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production cost.However,the low electronic conduc...Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production cost.However,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial development of LSBs.To solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb LiPSs.At the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction processes.The mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)calculations.The electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at 0.2C.And after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.展开更多
Batteries that utilize low-cost elemental sulfur and light metallic lithium as electrodes have great potential in achieving high energy density.However,building a lithium-sulfur(Li-S)full battery by controlling the el...Batteries that utilize low-cost elemental sulfur and light metallic lithium as electrodes have great potential in achieving high energy density.However,building a lithium-sulfur(Li-S)full battery by controlling the electrolyte volume generally produces low practical energy because of the limited electrochemical Li-S redox.Herein,the high energy/high performance of a Li-S full battery with practical sulfur loading and minimum electrolyte volume is reported.A unique hybrid architecture configured with Ni-Co metal alloy(NiCo)and metal oxide(NiCoO_(2))nanoparticles heterogeneously anchored in carbon nanotube-embedded selfstanding carbon matrix is fabricated as a host for sulfur.This work demonstrates the considerable improvement that the hybrid structure's high conductivity and satisfactory porosity promote the transport of electrons and lithium ions in Li-S batteries.Through experimental and theoretical validations,the function of NiCo and NiCoO_(2) nanoparticles as an efficient polysulfide mediator is established.These particles afford polysulfide anchoring and catalytic sites for Li-S redox reaction,thus improving the redox conversion reversibility.Even at high sulfur loading,the nanostructured Ni-Co metal alloy and metal oxide enable to have stable cycling performance under lean electrolyte conditions both in half-cell and full-cell batteries using a graphite anode.展开更多
For lithium-sulfur batteries(Li-S batteries),a high-content electrolyte typically can exacerbate the shuttle effect,while a lean electrolyte may lead to decreased Li-ion conductivity and reduced catalytic conversion e...For lithium-sulfur batteries(Li-S batteries),a high-content electrolyte typically can exacerbate the shuttle effect,while a lean electrolyte may lead to decreased Li-ion conductivity and reduced catalytic conversion efficiency,so achieving an appropriate electrolyte-to-sulfur ratio(E/S ratio)is essential for improving the battery cycling efficiency.A quasi-solid electrolyte(COF-SH@PVDF-HFP)with strong adsorption and high catalytic conversion was constructed for in situ covalent organic framework(COF)growth on highly polarized polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)fibers.COF-SH@PVDF-HFP enables efficient Li-ion conductivity with low-content liquid electrolyte and effectively suppresses the shuttle effect.The results based on in situ Fourier-transform infrared,in situ Raman,UV–Vis,X-ray photoelectron,and density functional theory calculations confirmed the high catalytic conversion of COF-SH layer containing sulfhydryl and imine groups for the lithium polysulfides.Lithium plating/stripping tests based on Li/COF-SH@PVDF-HFP/Li show excellent lithium compatibility(5 mAh cm^(-2) for 1400 h).The assembled Li-S battery exhibits excellent rate(2 C 688.7 mAh g^(-1))and cycle performance(at 2 C of 568.8 mAh g^(-1) with a capacity retention of 77.3%after 800 cycles).This is the first report to improve the cycling stability of quasi-solid-state Li-S batteries by reducing both the E/S ratio and the designing strategy of sulfhydryl-functionalized COF for quasi-solid electro-lytes.This process opens up the possibility of the high performance of solid-state Li-S batteries.展开更多
Polysulfide/ferricyanide flow batteries(S/Fe RFBs),with the advantages of abundant earth reservation low cost,high safety,and environmental friendliness,have attracted significant interest and demonstrated noteworthy ...Polysulfide/ferricyanide flow batteries(S/Fe RFBs),with the advantages of abundant earth reservation low cost,high safety,and environmental friendliness,have attracted significant interest and demonstrated noteworthy potential for practical applications.However,the battery performance,including the energy efficiency(EE),voltage efficiency(VE),and power density of the S/Fe RFBs remains low owing to the slow redox kinetics of polysulfide ions.To address these concerns,WS_(2)was selected as the booster and deposited on a commercial carbon felt electrode(WS_(2)-CF)to stimulate the redox reactions of polysulfide ions.With better hydrophilicity and smaller charge-transfer resistance,WS_(2)-CF exhibits enhanced electrochemical activity toward polysulfide redox reactions.Consequently,the battery performance of S/Fe RFB with WS_(2)-CF as the anode has been improved,with EE of 84%,VE of 84%,and a peak power density of 175.7 mW·cm^(-2),which are all higher than the cell only with the bare carbon felt(CF)as electrodes(76%,77%and 155.8 mW·cm^(-2),respectively).Furthermore,the cycling life of the S/Fe RFB with WS_(2)-CF has been prolonged to 2200 cycles with a capacity retention of 96% a 40 mA·cm^(-2)because of the good stability of WS_(2)-CF as the anode.Contrarily,under the same conditions,the S/Fe RFB without WS_(2)-CF terminated after 1500 cycles with a fast capacity decay.The successful utilization of WS_(2)as a booster on an electrode provides an efficient strategy for obtaining advanced S/Fe RFBs for practical applications.展开更多
Lithium-sulfur(Li-S) batteries are considered one of the most promising next-generation secondary batteries owing to their ultrahigh theoretical energy density.However,practical applications are hindered by the shuttl...Lithium-sulfur(Li-S) batteries are considered one of the most promising next-generation secondary batteries owing to their ultrahigh theoretical energy density.However,practical applications are hindered by the shuttle effect of soluble lithium polysulfides(Li PSs) and sluggish redox kinetics,which result in low active material utilization and poor cycling stability.Various copper-based materials have been used to inhibit the shuttle effect of Li PSs,owing to the strong anchoring effect caused by the lithiophilic/sulphilic sites and the accelerated conversion kinetics caused by excellent catalytic activity.This study briefly introduces the working principles of Li-S batteries,followed by a summary of the synthetic methods for copper-based materials.Moreover,the recent research progress in the utilization of various copper-based materials in cathodes and separators of Li-S batteries,including copper oxides,copper sulfides,copper phosphides,copper selenides,copper-based metal-organic frameworks(MOFs),and copper single-atom,are systematically summarized.Subsequently,three strategies to improve the electrochemical performance of copper-based materials through defect engineering,morphology regulation,and synergistic effect of different components are presented.Finally,our perspectives on the future development of copper-based materials are presented,highlighting the major challenges in the rational design and synthesis of high-performance Li-S batteries.展开更多
Lithium-sulfur (Li-S) batteries are considered appealing power sources due to their high theoretical energy density (2600 Wh kg-1), low cost, and environmental friendliness. However, their widespread applicability is ...Lithium-sulfur (Li-S) batteries are considered appealing power sources due to their high theoretical energy density (2600 Wh kg-1), low cost, and environmental friendliness. However, their widespread applicability is restricted by two scientific problems: sluggish sulfur reaction kinetics and severe polysulfide shuttle effects. Multifarious strategies have been developed to overcome these two obstacles and achieve high sulfur utilization and capacity retention. Among these strategies, the introduction of catalytic materials into the Li-S battery system can greatly accelerate sulfur conversion and effectively inhibit the polysulfide shuttle effects. Herein, we have comprehensively reviewed the recent progress of catalytic engineering for polysulfide conversion in high-performance lithium-sulfur batteries. First, various catalytic materials serve as sulfur hosts, functionalized separators, and electrolyte additives;the mechanisms by which these materials promote the conversion of polysulfides in Li-S batteries have been systematically summarized. The relationship of structure, preparation, property, advantages, and limitations of these catalytic materials are comprehensively presented. Subsequently, the advanced characterization techniques of these catalytic processes are discussed, shedding light on the fundamental understanding of catalytic effects for improved electrochemical performance. Furthermore, future design tactics for high-performance Li-S batteries are discussed.展开更多
基金financially supported by the National Natural Science Foundation of China(52172245)the Key Scientific and Technological Innovation Project of Shandong(2023CXGC010302)the Qingdao Flexible Materials Precision Die-cutting Technology Innovation Center。
文摘In lithium-sulfur batteries(LSBs),the limited utilization of sulfur and the sluggish kinetics of redox reaction significantly hinder their electrochemical performance,especially under high rates and high sulfur loadings.Here,we propose a novel separator structure with an interlayer composed of a vermiculite nanosheet combined with Ketjen Black(VMT@KB)for LSBs,facilitating efficient adsorption and rapid catalytic conversion toward lithium polysulfides(LiPSs).The VMT@KB nanosheets with an electrical double-layer structure and electronic conductivity are obtained through a high-temperature peeling process and Li^(+)exchange treatment in LiCl solution,followed by a mechanical combination process with KB.The results demonstrate that incorporating VMT@KB as an interlayer on a conventional separator enhances the conductivity and limits the LiPSs in the cathode region.The Li-S cell with VMT@KB interlayer shows satisfactory cycle and rate performance,especially in high sulfur loading.It exhibits a remarkable initial discharge capacity of 1225 mAh g^(-1)at 0.5 C and maintains a capacity of 816 mAh g^(-1)after 500 cycles.Besides,the discharge capacity remains 462 mAh g^(-1)even at 6 C.Moreover,the cell with high sulfur loading(8.2 mg cm^(-2))enables stable cycling for 100 cycles at 0.1 C with a discharge capacity of over1000 mAh g^(-1).
基金supported by National Natural Science Foundation of China(Nos.52472194,52101243)Natural Science Foundation of Guangdong Province,China(No.2023A1515012619)the Science and Technology Planning Project of Guangzhou(No.202201010565)。
文摘Owing to the advantages of high energy density,low cost,abundant sulfur reserves and environmentally friendly nature,lithium-sulfur batteries(LSBs)were considered as one of the potential candidates of energy storage devices for the next generation.However,the significant challenges in this area stem from the sluggish reaction kinetics of the insoluble Li_(2)S product and the capacity degradation triggered by the severe shuttle effect of polysulfides.It has been firmly established through numerous studies that modifying separators is an effective approach to enhance the properties of LSBs by facilitating the catalytic kinetic conversion and chemical adsorption of lithium polysulfides(Li PSs).In this work,we report a straightforward method for fabrication of the phosphorus doped porous CeO_(2)(P-CeO_(2))as separator modifier to accelerate the catalytic kinetic conversion of polysulfides and effectively inhibit the shuttle effect in LSBs.Through coin batteries tests,P-CeO_(2)modified PP separator(P-CeO_(2)//PP)exhibits remarkable electrochemical performance.It demonstrates a high initial capacity of 1180 mAh/g at 0.5 C,surpassing the performance of the bare CeO_(2)//PP separator.Furthermore,the P-CeO_(2)//PP separator demonstrates enhanced cycling stability,with a low-capacity fading rate of only 0.048%per cycle over 1000 cycles at 2 C.In compared with bare CeO_(2)//PP,P-CeO_(2)//PP exhibits high redox peak current,enhanced adsorption property of Li_(2)S_(6)and early Li_(2)S precipitation.These results highlight the superior performance of the P-CeO_(2)//PP separator compared to the bare CeO_(2)//PP separator.Hence,this research presents a successful strategy for the modification of LIBs separator with improved electrochemical performance and cycle stability.
基金the National Natural Science Foundation of China(Nos.51904344,52172264)the Natural Science Foundation of Hunan Province of China(Nos.2021JJ10060 and 2022GK2033).
文摘The intrinsic clustering behavior and kinetically sluggish conversion process of lithium polysulfides seriously limit the electrochemical reversibility of sulfur redox reactions in lithium-sulfur(Li-S)batteries.Here,we introduce molybdenum pentachloride(MoCl_(5))into the electrolyte which could coordinate with lithium polysulfides and inhibit their intrinsic clustering behavior,subsequently serving as an improved mediator with the bi-functional catalytic effect for Li_(2)S deposition and activation.Moreover,the coordination bonding and accelerated conversion reaction can also greatly suppress the dissolution and shuttling of polysulfides.Consequently,such polysulfide complexes enable the Li-S coin cell to exhibit good longterm cycling stability with a capacity decay of 0.078%per cycle after 400 cycles at 2 C,and excellent rate performance with a discharge capacity of 589 mAh/g at 4 C.An area capacity of 3.94 mAh/cm^(2)is also achieved with a high sulfur loading of 4.5mg/cm^(2)at 0.2 C.Even at-20℃,the modified cell maintains standard discharge plateaus with low overpotential,delivering a high capacity of 741 mAh/g at 0.2 C after 80 cycles.The low-cost and convenient MoCl_(5)additive opens a new avenue for the effective regulation of polysulfides and significant enhancement in sulfur redox conversion.
基金supported by the Natural Science Foundation of China(22309179)the Natural Science Foundation of China(12404049)+4 种基金Natural Science Foundation of Ningxia(2023AAC01003)Guangdong Basic and Applied Basic Research Foundation(2021A1515110156,2022A1515010724,2023A1515110521,2023B1515120095,2024A1515011260)Science and Technology Program of Guangzhou(No.2019050001)the Outstanding Youth Project of Guangdong Natural Science Foundation(2021B1515020051)Dalian Revitalization Talents Program(No.2022RG01).
文摘Developing electrocatalysts to inhibit polysulfide shuttling and expedite sulfur species conversion is vital for the evolution of Lithium-sulfur(Li-S)batteries.This work provides a facile strategy to design an intimate heterostructure of MIL-88A@CdS as a sulfur electrocatalyst combining high sulfur adsorption and accelerated polysulfide conversion.The MIL-88A can give a region of high-ordered polysulfide adsorption,whereas the CdS is an effective nanoreactor for the sulfur reduction reaction(SRR).Notedly,the significant size difference between MIL-88A and CdS enables the unique heterostructure interactions.The largesize MIL-88A ensures a uniform distribution of CdS nanoparticles as a substrate.This configuration facilitates control of the initial polysulfide adsorption position relative to its final deposition site as lithium sulfide.The heterostructure also demonstrates rapid transport and efficient conversion of lithium polysulfides.Consequently,the Li-S battery with MIL-88A@CdS heterostructure modified separator delivers exceptional performance,achieving an areal capacity exceeding 6 mAh cm^(−2),an excellent rate capability of 980 mAh g^(−1) at 5 C,and notable cycling stability in a 2 Ah pouch cell over 100 cycles.This work is significant for elucidating the relationship between heterostructure and electrocatalytic performance,providing great insights for material design aimed at highly efficient future electrocatalysts in practical applications.
基金supported by the Scientific Research Program Funded by Education Department of Shaanxi Provincial Government(No.22JK0411)the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-QN-0165)the National Natural Science Foundation of China(No.21603109).
文摘Lithium-sulfur batteries are considered to be a new generation of high energy density batteries due to their non-toxicity,low cost and high theoretical specific capacity.However,the development of practical lithium-sulfur batteries is seriously impeded by the sluggish multi-electron redox reaction of sulfur species and obstinate shuttle effect of polysulfides.In this study,a porous lanthanum oxychloride(LaOCl)nanofiber is designed as adsorbent and electrocatalyst of polysulfides to regulate the redox kinetics and suppress shuttling of sulfur species.Benefiting from the porous architecture and luxuriant active site of LaOCl nanofibers,the meliorative polarization effect and sulfur expansion can be accomplished.The LaOCl/S electrode exhibits an initial discharge specific capacity of 1112.3 mAh/g at 0.1 C and maintains a superior cycling performance with a slight decay of 0.02%per cycle over 1000 cycles at 1.0 C.Furthermore,even under a high sulfur loading of 4.6mg/cm^(2),the S cathode with LaOCl nanofibers still retains a high reversible areal capacity of 4.2 mAh/cm^(2)at 0.2 C and a stable cycling performance.Such a porous host expands the application of rare earth based catalysts in lithium-sulfur batteries and provides an alternative approach to facilitate the polysulfides conversion kinetics.
基金financially supported by the National Natural Science Foundation of China(U22A20113,52261135543)。
文摘Lithium-sulfur(Li-S)batteries with high energy density suffer from the soluble lithium polysulfide species,Traditional metal sulfides containing a single metal element used as electrocatalysts for Li-S batteries commonly have limited catalytic abilities to improve battery performance.Herein,based on the Hume-Rothery rule and solvothermal method,the high-entropy sulfide NiCoCuTiVS_(x)derived from Co_(9)S_(8)was designed and synthesized,to realize the combination of small local strain and excellent catalytic performance.With all five metal elements(Ni,Co,Cu,Ti,and V)capable of chemical interactions with soluble polysulfides,NiCoCuTiVS_(x)exhibited strong chemical confinement of polysulfides and promoted fast kinetics for polysulfides conversion.Consequently,the S/NiCoCuTiVS_(x)cathode can maintain a high discharge capacity of 968.9 mA h g^(-1)after 200 cycles at 0.5 C and its capacity retention is 1.3 times higher than that of S/Co_(9)S_(8).The improved cycle stability can be attributed to the synergistic effect originating from the multiple metal elements,coupled with the reduced nucleation and activation barriers of Li_(2)S.The present work opens a path to explore novel electrocatalyst materials based on high entropy materials for the achievement of advanced Li-S batteries.
基金supported by National Natural Science Foundation of China(Nos.52472194,52101243)Natural Science Foundation of Guangdong Province,China(No.2023A1515012619)the Science and Technology Planning Project of Guangzhou(No.202201010565).
文摘Lithium-sulfur batteries(LSBs)are considered as the most promising energy storage technologies owing to their large theoretical energy density(2500Wh/kg)and specific capacity(1675 mAh/g).However,the heavy shuttle effect of polysulfides and the growth of lithium dendrites greatly hinder their further development and commercial application.In this paper,cobalt-molybdenum bimetallic carbides heterostructure(Co_(6)Mo_(6)C_(2)@Co@NC)was successfully prepared through chemical etching procedure of ZIF-67 precursor with sodium molybdate and the subsequent high temperature annealing process.The obtained dodecahedral Co_(6)Mo_(6)C_(2)@Co@NC with hollow and porous structure provides large specific surface area and plentiful active sites,which speeds up the chemisorption and catalytic conversion of polysulfides,thus mitigating the shuttle effect of polysulfides and the generation of lithium dendrites.When applied as the LSBs separator modifier layer,the cell with modified separator present excellent rate capability and durable cycling stability.In particular,the cell with Co_(6)Mo_(6)C_(2)@Co@NC/PP separator can maintain the high capacity of 738 mAh/g at the current density of 2 C and the specific capacity of 782.6 mAh/g after 300 cycles at 0.5 C,with the coulombic efficiency(CE)near to 100%.Moreover,the Co_(6)Mo_(6)C_(2)@Co@NC/PP battery exhibits the impressive capacity of 431 mAh/g in high sulfur loading(4.096 mg/cm^(2))at 0.5 C after 200 cycles.This work paves the way for the development of bimetallic carbides heterostructure multifunctional catalysts for durable Li-S battery applications and reveals the synergistic regulation of polysulfides and lithium dendrites through the optimization of the structure and composition.
基金Financial supports from the National Natural Science Foundation of China(Grant Number:22265018)the Key Project of Natural Science Foundation of Jiangxi Province(Grant Number:20232ACB204010)+1 种基金the Graduate Innovative Special Fund Projects of Jiangxi Province(Grant Number:YC2024-B034)the Jiangxi Province Key Laboratory of Lithiumion Battery Materials and Application(Grant Number:2024SSY05202)are gratefully acknowledged。
文摘Metal phosphosulfides(MPS_(x)),especially BiPS_(4),have emerged as promising anode candidates for sodiumion batteries,distinguished by distinctive multinary redox chemistry,open tunnel-type structure,and high theoretical capacity(>1000 m Ah g^(-1)).However,their practical implementation is fundamentally limited by polysulfide dissolution/shuttling and structural instability during prolonged cycling.Herein,we develop a groundbreaking two-stage metal-organic framework(MOF)-engineered compositing strategy through which Bi-MOF-derived BiPS_(4)/C pillars are robustly armored with conductive Ni-HHTP(HHTP=2,3,6,7,10,11-hexahydroxytriphenylene)nanorods.Density functional theory calculations reveal that this design achieves dual functionality:increased carrier density for enhanced charge transport dynamics and effective polysulfide adsorption to inhibit dissolution.The fabricated BiPS_(4)/C@Ni-HHTP composite delivers remarkable electrochemical properties,including high initial charge/discharge specific capacities of 1063.6/1181.3 mAh g^(-1)at 0.1 A g^(-1)and outstanding long-term stability with 99.2% capacity retention after 2000 cycles at 2 A g^(-1).Such superb performance stems from the perfect synergy of the inherent high-capacity redox behavior of BiPS_(4),the buffering effect of MOF-derived carbon,and the conductivity,adsorption sites and mechanical resilience of Ni-HHTP.This work establishes a new design paradigm for MPS_(x)materials,demonstrating how to simultaneously overcome conductivity limitations and shuttle effects in conversion-type electrodes.
基金supported by the National Natural Science Foundation of China(22201244,22374125,21971221 and 21773203)the Yangzhou University Interdisciplinary Research Foundation for Chemistry Discipline of Targeted Support(yzuxk202010)+2 种基金High-Level Entrepreneurial and Innovative Talents Program of Jiangsu‘Qing Lan Project’in Colleges and Universities of Jiangsu ProvinceLvyangjinfeng Talent Program of Yangzhou,China Postdoctoral Science Foundation(2022M722688)。
文摘The polysulfides shuttle effect,sluggish sulfur redox kinetics and the corrosion of the Li anode have become important factors limiting the commercial application of lithium-sulfur batteries(LSBs).Herein,the polyoxometalate(POM)nanoclusters with high catalytic activity and cobalt selenide with strong polarity are initially complemented to construct a PMo_(12)/CoSe_(2)@NC/CNTs multifunctional separator that can simultaneously solve the above problems.A series of experimental and theoretical results demonstrate that the Keggin-type POM,H_(3)PMo_(12)O_(40)nH_(2)O(PMo_(12))nanoclusters could function as catalytic centers for sulfur-involved transformations,with the CoSe_(2)nanoparticles serving as adsorption sites for soluble polysulfides.Accordingly,the assembled battery with the PMo_(12)/CoSe_(2)@NC/CNTs modified separator achieves an initial discharge capacity of 1263.79 mA h g^(-1),maintaining 635.77 mA h g^(-1),with a capacity decay rate of 0.06%per cycle after 500 cycles at 3C.This work provides a strategic approach for incorporating POM nanoclusters with polar periodic nanomaterials in LSB separators,contributing to the development of multifunctional separator materials,thus promoting the advancement of energy storage systems.
基金financially supported by Jilin province science and technology department(No.20230402059GH)Changchun Science and Technology Bureau(No.23YQ11)+4 种基金Jilin Province Science and Technology Department major science and technology project(Nos.20220301004GX and 20220301005GX)Key Subject Construction of Physical Chemistry of Northeast Normal University(No.2412022XK004)the National Natural Science Foundation of China(No.22102020)the Swedish Foundation for International Cooperation in Research and Higher Education(No.KO2017-7351)Swedish Energy Agency(No.P2020-90216)。
文摘Developing effective heterostructure strategies to mitigate the shuttling effect and accelerate lithium polysulfide(Li PS)conversion remains a critical challenge in lithium–sulfur(Li–S)batteries.Here,we report the first carbon–free VO_(2)–VS_(2)heterostructure material synthesized via in situ sulfurization,applied as a modifier on a commercial polypropylene(PP)separator(denoted as VO_(2)–VS_(2)@PP).The as–prepared VO_(2)–VS_(2)nanorods synergistically combine the high absorptivity of VO_(2)with the efficient catalytic properties of VS_(2),simultaneously enhancing Li PS anchoring and promoting its conversion.We systematically investigate the influence of material composition on battery performance,leveraging these functional attributes,Li–S cells incorporating VO_(2)–VS_(2)@PP exhibit exceptional cycle stability(over 500cycles at 1C),impressive rate performance(807 m Ah.g^(–1)at 5C),desirable reversibility(49.9%capacity retention after 300 cycles at 5C)and exceptional pouch cell performance(3.65 m Ah.cm^(–2)after 50 stable cycles at 0.1C).This study underscores the potential of tailored heterostructures in realizing high–performance Li–S batteries,offering new insights for next–generation energy storage solutions.
基金supported by the National Key Research and Development Program of China(No.2019YFA0210600)the National Natural Science Foundation of China(Nos.51922103 and 51972326)+1 种基金the Natural Science Foundation of Jiangxi Province(Nos.20224BAB204002 and GJJ211320)Jingdezhen Science and Technology Bureau(No.20212GYZD009-15)。
文摘Solid-state polymer sodium batteries(SPSBs)are promising candidates for achieving higher energy density and safe energy storage.However,interface issues between oxide cathode and solid-state polymer electrolyte are a great challenge for their commercial application.In contrast,soft sulfur-based materials feature better interface contact and chemical compatibility.Herein,an interfacial compatible polysulfide Ti_(4)P_(8)S_(29) with robust Ti-S bonding and a highly active P-S unit is tailored as a high-performance cathode for SPSBs.The Ti_(4)P_(8)S_(29) cathode possesses a three-dimensional channel structure for offering ample Na+diffusion pathways.The assembled poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)-based SPSBs deliver a discharge capacity of 136 mAh·g^(-1)at 0.5C after 200 cycles.Furthermore,a discharge capacity of 88 mAh·g^(-1)is retained after 600 cycles at a high rate of 2C,surpassing many cathode materials in SPSBs.A dual-site redox of Ti^(4+)/Ti^(3+)and S^(-)/S^(2-)is verified by X-ray photoelectron spectroscopy(XPS)and cyclic voltammetry(CV)tests.Interestingly,a refined locally-ordered amorphous structure is unveiled by in situ and ex situ characterizations.The as-formed electrode structure with lots of open channels and isotropic properties are more beneficial for ion diffusion on the interface of electrode and solid-state polymer electrolytes(SPEs),leading to faster Na+diffusion kinetics.This work proposes a strategy of modulating open-channel to boost conversion kinetics in polysulfide cathode and opens a new pathway for designing high-performance SPSBs.
基金supported by the National Natural Science Foundation of China(Grant No.52372281)the Fundamental Research Funds for the Central Universities(2232020G-07)+3 种基金the foundation of Shanghai Institute of Technology(grant no.YJ2022-37)the Graduate Student Innovation Fund of Donghua University(CUSF-DH-D-2022007)the State Key Laboratory of Advanced Fiber Materials(KF2517)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning。
文摘Lithium-sulfur(Li-S)batteries promise high energy density but suffer from low conductivity,polysulfide shuttling,and sluggish conversion kinetics.The construction of heterointerfaces is an effective strategy for enhancing both polysulfide adsorption and conversion;however,the poor lattice compatibility in the heterointerface formed by different materials hinders interfacial charge transfer.In response to these challenges,herein,a biphasic homojunction of TiO_(2)enriched with oxygen vacancies and decorated with nitrogen-doped carbon nanotubes(B-TiO_(2-x)@NCNT)was designed to simultaneously enhance adsorption ability and catalytic activity.This homojunction interface composed of rutile(110)and anatase(101)plane exhibits excellent compatibility,and density functional theory(DFT)calculations reveal that this biphasic interface possesses a much higher binding energy to polysulfides compared to single-phase TiO_(2).Additionally,NCNTs are in situ grown on both interior and exterior surfaces of the hollow TiO_(2)nanospheres,facilitating rapid electron transfer for the encapsulated sulfur.The homojunction interface synergistically leverages the oxygen vacancies and highly conductive NCNTs to enhance the bidirectional catalytic activity for polysulfide conversion.Therefore,in this multifunctional sulfur-host,polysulfides are first strongly adsorbed at the homojunction interfaces and subsequently undergo smooth conversion,nucleation,and decomposition,completing a rapid sulfur redox cycle.The assembled Li-S battery delivered a high specific capacity of 1234.3 mAh g^(-1)at 0.2 C,long cycling stability for over 1000 cycles at 5 C with a low decay rate of 0.035%,and exciting areal capacity at a high sulfur loading of 5.6 mg cm^(-2)for 200cycles.
基金supported by the National Natural Science Foundation of China(Nos.52105575&52205593)the Fundamental Research Funds for the Central Universities(No.QTZX23063)+1 种基金the Proof of Concept Foundation of Xidian University Hangzhou Institute of Technology(Nos.GNYZ2023YL0302&GNYZ2023QC0401)the Aeronautical Science Foundation of China(No.2022Z073081001)。
文摘Lithium-sulfur batteries(LSBs)have already developed into one of the most promising new-generation high-energy density electrochemical energy storage systems with outstanding features including high-energy density,low cost,and environmental friendliness.However,the development and commercialization path of LSBs still presents significant limitations and challenges,particularly the notorious shuttle effect triggered by soluble longchain lithium polysulfides(LiPSs),which inevitably leads to low utilization of cathode active sulfur and high battery capacity degradation,short cycle life,etc.Substantial research efforts have been conducted to develop various sulfur host materials capable of effectively restricting the shuttle effect.This review firstly introduces the fundamental electrochemical aspects of LSBs,followed by a comprehensive analysis of the mechanism underlying the shuttle effect in Li–S batteries and its profound influence on various battery components as well as the overall battery performance.Subsequently,recent advances and strategies are systematically reviewed,including physical confinement,chemisorption,and catalytic conversion of sulfur hosts for restricting LiPSs shuttle effects.The interplay mechanisms of sulfur hosts and LiPSs are discussed in detail and the structural advantages of different host materials are highlighted.Furthermore,key insights for the rational design of advanced host materials for LSBs are provided,and the upcoming challenges and the prospects for sulfur host materials in lithium-sulfur batteries are also explored.
基金supported by the National Natural Science Foundation of China(22075091)the Natural Science Foundation of Hubei Province(Grant No.2021CFA066)。
文摘Li-S batteries are regarded as one of the most promising candidates for next-generation battery systems with high energy density and low cost.However,the dissolution-precipitation reaction mechanism of the sulfur(S)cathode enhances the kinetics of the redox processes of the insulating sulfu r,which also arouses the notorious shuttle effect,leading to serious loss of S species and corrosion of Li anode.To get a balance between the shuttle restraining and the kinetic property,a combined strategy of electrolyte regulation and cathode modification is proposed via introducing 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoroprpyl ether(HFE)instead of 1,2-dimethoxyethane(DME),and SeS_(7)instead of S_8.The introduction of HFE tunes the solvation structure of the LiTFSI and the dissolution of intermediate polysulfides with Se doping(LiPSSes),and optimize the interface stability of the Li anode simultaneously.The minor Se substitution compensates the decrease in kinetic due to the decreased solubility of LiPSs.In this way,the Li-SeS_(7)batteries deliver a reversible capacity of 1062 and 1037 mAh g^(-1)with 2.0 and 5.5 mg SeS_(7)cm^(-2)loading condition,respectively.Besides,an electrolyte-electrode loading model is established to explain the relationship between the optimal electrolyte and cathode loading.It makes more sense to guide the electrolyte design for practical Li-S batteries.
基金financially supported by the National Natural Science Foundation of China(No.52130101)the Project of Science and Technology Development Plan of Jilin Province in China(Nos.20210402058GH and 20220201114GX)。
文摘Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production cost.However,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial development of LSBs.To solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb LiPSs.At the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction processes.The mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)calculations.The electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at 0.2C.And after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.
基金supported by the National Research Foundation of Korea (NRF)grant funded by the Korean government (MSIT) (NRF-2022R1C1C1011058)supported by the Korea Institute for Advancement of Technology (KIAT)grant funded by the Korean Government (MOTIE) (P0012748,HRD Program for Industrial Innovation).
文摘Batteries that utilize low-cost elemental sulfur and light metallic lithium as electrodes have great potential in achieving high energy density.However,building a lithium-sulfur(Li-S)full battery by controlling the electrolyte volume generally produces low practical energy because of the limited electrochemical Li-S redox.Herein,the high energy/high performance of a Li-S full battery with practical sulfur loading and minimum electrolyte volume is reported.A unique hybrid architecture configured with Ni-Co metal alloy(NiCo)and metal oxide(NiCoO_(2))nanoparticles heterogeneously anchored in carbon nanotube-embedded selfstanding carbon matrix is fabricated as a host for sulfur.This work demonstrates the considerable improvement that the hybrid structure's high conductivity and satisfactory porosity promote the transport of electrons and lithium ions in Li-S batteries.Through experimental and theoretical validations,the function of NiCo and NiCoO_(2) nanoparticles as an efficient polysulfide mediator is established.These particles afford polysulfide anchoring and catalytic sites for Li-S redox reaction,thus improving the redox conversion reversibility.Even at high sulfur loading,the nanostructured Ni-Co metal alloy and metal oxide enable to have stable cycling performance under lean electrolyte conditions both in half-cell and full-cell batteries using a graphite anode.
基金This research was supported by the National Natural Science Foundation of China(52202104)the Joint Funds of the Zhejiang Provincial Natural Science Foundation of China(LZY23B030002)+5 种基金the China Postdoctoral Science Foundation(2021T140433,2020M683408)the Quzhou Science and Technology Bureau Project(2022D015,2023D023)the International Cooperation Projects of Sichuan Provincial Department of Science and Technology(2021YFH0126)the Fundamental Research Funds for the Central Universities(ZYGX2020ZB016)the Key Research and Development Program of Yunnan Province China(202103AA080019)Yunnan Major Scientific and Technological Projects(202202AG050003).
文摘For lithium-sulfur batteries(Li-S batteries),a high-content electrolyte typically can exacerbate the shuttle effect,while a lean electrolyte may lead to decreased Li-ion conductivity and reduced catalytic conversion efficiency,so achieving an appropriate electrolyte-to-sulfur ratio(E/S ratio)is essential for improving the battery cycling efficiency.A quasi-solid electrolyte(COF-SH@PVDF-HFP)with strong adsorption and high catalytic conversion was constructed for in situ covalent organic framework(COF)growth on highly polarized polyvinylidene fluoride-hexafluoropropylene(PVDF-HFP)fibers.COF-SH@PVDF-HFP enables efficient Li-ion conductivity with low-content liquid electrolyte and effectively suppresses the shuttle effect.The results based on in situ Fourier-transform infrared,in situ Raman,UV–Vis,X-ray photoelectron,and density functional theory calculations confirmed the high catalytic conversion of COF-SH layer containing sulfhydryl and imine groups for the lithium polysulfides.Lithium plating/stripping tests based on Li/COF-SH@PVDF-HFP/Li show excellent lithium compatibility(5 mAh cm^(-2) for 1400 h).The assembled Li-S battery exhibits excellent rate(2 C 688.7 mAh g^(-1))and cycle performance(at 2 C of 568.8 mAh g^(-1) with a capacity retention of 77.3%after 800 cycles).This is the first report to improve the cycling stability of quasi-solid-state Li-S batteries by reducing both the E/S ratio and the designing strategy of sulfhydryl-functionalized COF for quasi-solid electro-lytes.This process opens up the possibility of the high performance of solid-state Li-S batteries.
基金financially supported by the NationalNatural Science Foundation of China(No.22209015)Scientific Research Foundation of Hunan Provincial Education Department(Nos.21A0195 and 21C0215)100 Talented Team of Hunan Province(No.XiangZu[2016]91)。
文摘Polysulfide/ferricyanide flow batteries(S/Fe RFBs),with the advantages of abundant earth reservation low cost,high safety,and environmental friendliness,have attracted significant interest and demonstrated noteworthy potential for practical applications.However,the battery performance,including the energy efficiency(EE),voltage efficiency(VE),and power density of the S/Fe RFBs remains low owing to the slow redox kinetics of polysulfide ions.To address these concerns,WS_(2)was selected as the booster and deposited on a commercial carbon felt electrode(WS_(2)-CF)to stimulate the redox reactions of polysulfide ions.With better hydrophilicity and smaller charge-transfer resistance,WS_(2)-CF exhibits enhanced electrochemical activity toward polysulfide redox reactions.Consequently,the battery performance of S/Fe RFB with WS_(2)-CF as the anode has been improved,with EE of 84%,VE of 84%,and a peak power density of 175.7 mW·cm^(-2),which are all higher than the cell only with the bare carbon felt(CF)as electrodes(76%,77%and 155.8 mW·cm^(-2),respectively).Furthermore,the cycling life of the S/Fe RFB with WS_(2)-CF has been prolonged to 2200 cycles with a capacity retention of 96% a 40 mA·cm^(-2)because of the good stability of WS_(2)-CF as the anode.Contrarily,under the same conditions,the S/Fe RFB without WS_(2)-CF terminated after 1500 cycles with a fast capacity decay.The successful utilization of WS_(2)as a booster on an electrode provides an efficient strategy for obtaining advanced S/Fe RFBs for practical applications.
基金supported by the National Natural Science Foundation of China (No.51962002)Natural Science Foundation of Guangxi (No.2022GXNSFAA035463)。
文摘Lithium-sulfur(Li-S) batteries are considered one of the most promising next-generation secondary batteries owing to their ultrahigh theoretical energy density.However,practical applications are hindered by the shuttle effect of soluble lithium polysulfides(Li PSs) and sluggish redox kinetics,which result in low active material utilization and poor cycling stability.Various copper-based materials have been used to inhibit the shuttle effect of Li PSs,owing to the strong anchoring effect caused by the lithiophilic/sulphilic sites and the accelerated conversion kinetics caused by excellent catalytic activity.This study briefly introduces the working principles of Li-S batteries,followed by a summary of the synthetic methods for copper-based materials.Moreover,the recent research progress in the utilization of various copper-based materials in cathodes and separators of Li-S batteries,including copper oxides,copper sulfides,copper phosphides,copper selenides,copper-based metal-organic frameworks(MOFs),and copper single-atom,are systematically summarized.Subsequently,three strategies to improve the electrochemical performance of copper-based materials through defect engineering,morphology regulation,and synergistic effect of different components are presented.Finally,our perspectives on the future development of copper-based materials are presented,highlighting the major challenges in the rational design and synthesis of high-performance Li-S batteries.
基金financially supported by National Natural Science Foundation of China(Nos.52164030 and 22179055)Natural Science Foundation of Jiangxi Province(Nos.20202ACBL204007 and 20224BAB204004)Program of Qingjiang Excellent Young Talents of Jiangxi University of Science and Technology(No.JXUSTQJYX2019010).
文摘Lithium-sulfur (Li-S) batteries are considered appealing power sources due to their high theoretical energy density (2600 Wh kg-1), low cost, and environmental friendliness. However, their widespread applicability is restricted by two scientific problems: sluggish sulfur reaction kinetics and severe polysulfide shuttle effects. Multifarious strategies have been developed to overcome these two obstacles and achieve high sulfur utilization and capacity retention. Among these strategies, the introduction of catalytic materials into the Li-S battery system can greatly accelerate sulfur conversion and effectively inhibit the polysulfide shuttle effects. Herein, we have comprehensively reviewed the recent progress of catalytic engineering for polysulfide conversion in high-performance lithium-sulfur batteries. First, various catalytic materials serve as sulfur hosts, functionalized separators, and electrolyte additives;the mechanisms by which these materials promote the conversion of polysulfides in Li-S batteries have been systematically summarized. The relationship of structure, preparation, property, advantages, and limitations of these catalytic materials are comprehensively presented. Subsequently, the advanced characterization techniques of these catalytic processes are discussed, shedding light on the fundamental understanding of catalytic effects for improved electrochemical performance. Furthermore, future design tactics for high-performance Li-S batteries are discussed.
