Search

Lithium-sulfur battery (LSB) is renowned for its high energy density storage property yet its development has faced significant challenges including the shuttle effect and slow reaction rates. A vanadium nitride quantum dots decorated N-doped hollow carbon nanosphere (VN@CS) is thus synthesized and applied as the sulfur host material in LSBs. Experimental results demonstrate the efficient adsorption and catalytic conversion character of the polar VN for soluble lithium polysulfides (LiPSs), contributing to an effective inhibition of the shuttle effect and acceleration of LiPSs conversion. Consequently, the S/VN@CS cathode exhibits a high specific capacity of 849.1 mA h g−1 at a high current density of 4 C, along with the long cycling performance, achieving 1000 cycles with a low capacity decay rate of 0.038% per cycle at 2 C. The work presents the successful combination of small yet highly efficient quantum dots with a conductive substrate to achieve excellent electrochemical performances of LSBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • A stable double shell of S@MnO 2 @MXene is applied in Li-S batteries. • The loading mass of sulfur can be regulated to 5.88 mg cm−2. • The MnO 2 @MXene composite material can accelerate the adsorption and catalytic conversion of LiPSs. • The cathode with high sulfur loading mass exhibits excellent cyclic stability. Lithium-sulfur (Li-S) batteries represent the most promising next-generation energy storage systems because of their high theoretical specific capacity and energy density. However, the severe shuttle effect and volume expansion of sulfur cathodes have impeded their commercial viability. Hence, accelerating the conversion of lithium polysulfides (LiPSs) is crucial for achieving efficient Li-S batteries. In this study, we employ a straightforward electrostatic self-assembly method to coat ultra-thin MXene nanosheets onto a S@MnO 2 core–shell structure, resulting in a highly conductive three-dimensional network. This unique structure not only suppresses the diffusion of LiPSs but also accelerates electron and ion transfer, ensuring a rapid and efficient conversion of LiPSs. The CV curves of symmetrical cells and the Li 2 S deposition curves demonstrate a significant improvement in the catalytic performance of batteries with S@MnO 2 @MXene. The capacity of Li-S batteries achieved an impressive 842 mAh/g at the current density of 1C, with a minimal capacity decay of only 0.84 mAh/g per cycle within 500 cycles. Additionally, increasing the sulfur loading mass to 5.88 mg cm−2 resulted in an areal capacity of 6.33 mAh cm−2, demonstrating practical application potential. [ABSTRACT FROM AUTHOR]

Lithium‐sulfur batteries (LiSBs) with high energy density still face challenges on sluggish conversion kinetics, severe shuttle effects of lithium polysulfides (LiPSs), and low blocking feature of ordinary separators to LiPSs. To tackle these, a novel double‐layer strategy to functionalize separators is proposed, which consists of Co with atomically dispersed CoN4 decorated on Ketjen black (Co/CoN4@KB) layer and an ultrathin 2D Ti3C2Tx MXene layer. The theoretical calculations and experimental results jointly demonstrate metallic Co sites provide efficient adsorption and catalytic capability for long‐chain LiPSs, while CoN4 active sites facilitate the absorption of short‐chain LiPSs and promote the conversion to Li2S. The stacking MXene layer serves as a microscopic barrier to further physically block and chemically anchor the leaked LiPSs from the pores and gaps of the Co/CoN4@KB layer, thus preserving LiPSs within efficient anchoring‐conversion reaction interfaces to balance the accumulation of "dead S" and Li2S. Consequently, with an ultralight loading of Co/CoN4@KB‐MXene, the LiSBs exhibit amazing electrochemical performance even under high sulfur loading and lean electrolyte, and the outperforming performance for lithium‐selenium batteries (LiSeBs) can also be achieved. This work exploits a universal and effective strategy of a double‐layer functionalized separator to regulate the equilibrium adsorption‐catalytic interface, enabling high‐energy and long‐cycle LiSBs/LiSeBs. [ABSTRACT FROM AUTHOR]

Due to the higher conductivity of selenium than sulfur, lithium selenium (Li–Se) batteries have received increasing attention. However, the shuttle effect and the slow conversion kinetics of polyselenides have resulted in poor cycling performance of Li–Se batteries. In this work, a CoTe2 and MOF derived composite (CoTe2-MD) was designed and synthesized. As a dual-functional matrix, the MOF derivative acted as an adsorbent and effectively reduced the dissolution of the polyselenides in ether electrolytes via physical/chemical absorption. CoTe2 acted as an electrocatalyst, which accelerated the conversion reaction of the polyselenides and improved the redox kinetics of the reactions. The results proved that the dual-functional matrix consisting of the adsorbent and electrocatalyst further suppressed the shuttle effect and significantly improved the cycle stability of the Li–Se batteries. At 0.5C, the Se/CoTe2-MD electrode showed 540.4 mA h g−1 of initial discharge capacity. Even after 200 cycles, it still maintained a reversible capacity of 454.1 mA h g−1, with a decay rate of only 0.08% per cycle. [ABSTRACT FROM AUTHOR]

Aqueous zinc–iodine batteries are considered to be one of the most promising devices for future electrical energy storage due to their low cost, high safety, high theoretical specific capacity, and multivalent properties. However, the shuttle effect currently faced by zinc–iodine batteries causes the loss of cathode active material and corrosion of the zinc anodes, limiting the large-scale application of zinc–iodine batteries. In this paper, the electrochemical processes of iodine conversion and the zinc anode, as well as the induced mechanism of the shuttle effect, are introduced from the basic configuration of the aqueous zinc–iodine battery. Then, the inhibition strategy of the shuttle effect is summarized from four aspects: the design of cathode materials, electrolyte regulation, the modification of the separator, and anode protection. Finally, the current status of aqueous zinc–iodine batteries is analyzed and recommendations and perspectives are presented. This review is expected to deepen the understanding of aqueous zinc–iodide batteries and is expected to guide the design of high-performance aqueous zinc–iodide batteries. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) are extensively studied owing to their high theoretical capacity and low cost. However, the shuttle effect of lithiumsulfur batteries hinders their development. In this study, we obtained a modified separator to inhibit the shuttle effect through physical and chemical adsorption. The CoS2 nanosheets (CSNS) derived from a cobaltbased metal-organic framework (Co-MOF) were synthesized by a simple twostep method involving hydrothermal sulfurization and thermal decomposition. The material was then coated onto a Polypropylene (PP) separator using vacuum filtration and assembled into a LSB for systematic testing and research of its electrochemical performance and mechanism. Thanks to the intrinsic polarity of the CSNs and more active sites brought by the Co-MOF material, the modified separator has strong chemical adsorption and catalytic effects on polysulfides, anchoring and accelerating their conversion. When using the CSNs-PP separator, the LSB achieved a high initial capacity of 1002.4 mAh g−1 at 1 C, with only a 0.099% decay per cycle after 500 cycles. The modified separator effectively alleviating the shuttle effect, reducing internal resistance, weakening reaction polarization, and improving the specific capacity, stability, and reversibility of the battery. [ABSTRACT FROM AUTHOR]

The shuttle effect of polysulfides poses a significant obstacle to the commercialization of lithium-sulfur (Li–S) batteries. Covalent organic frameworks have been widely used in Li–S batteries as porous crystalline materials to suppress the shuttle effect. Herein, a 3,5-bis(trifluoromethyl)benzyl (BTFMB-TzDa) modified triazine-based covalent organic framework was synthesized. The high electronegativity and large steric hindrance of the BTFMB-TzDa modified separator successfully suppressed the diffusion of polysulfides, leading to improved capacity and cyclic stability of Li–S batteries. Cells with the BTFMB-TzDa modified separator exhibited a high initial capacity of 1205 mA h g−1 at 0.2C and 657 mA h g−1 at 3.0C. Furthermore, the capacity still remained at 501 mA h g−1 after 500 cycles. The BTFMB-TzDa modified separator provides an alternative strategy for the construction of high-performance Li–S batteries. [ABSTRACT FROM AUTHOR]

Highlights: The electrochemical principles/mechanism of Li–S batteries and origin of the shuttle effect have been discussed. The efficient strategies have been summarized to inhibit the shuttle effect. The recent advances of inhibition of shuttle effect in Li–S batteries for all components from anode to cathode. Lithium–sulfur (Li–S) batteries are supposed to be one of the most potential next-generation batteries owing to their high theoretical capacity and low cost. Nevertheless, the shuttle effect of firm multi-step two-electron reaction between sulfur and lithium in liquid electrolyte makes the capacity much smaller than the theoretical value. Many methods were proposed for inhibiting the shuttle effect of polysulfide, improving corresponding redox kinetics and enhancing the integral performance of Li–S batteries. Here, we will comprehensively and systematically summarize the strategies for inhibiting the shuttle effect from all components of Li–S batteries. First, the electrochemical principles/mechanism and origin of the shuttle effect are described in detail. Moreover, the efficient strategies, including boosting the sulfur conversion rate of sulfur, confining sulfur or lithium polysulfides (LPS) within cathode host, confining LPS in the shield layer, and preventing LPS from contacting the anode, will be discussed to suppress the shuttle effect. Then, recent advances in inhibition of shuttle effect in cathode, electrolyte, separator, and anode with the aforementioned strategies have been summarized to direct the further design of efficient materials for Li–S batteries. Finally, we present prospects for inhibition of the LPS shuttle and potential development directions in Li–S batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li-S) batteries are considered one of the most promising energy storage systems due to their high theoretical capacity, high theoretical capacity density, and low cost. However, challenges such as poor conductivity of sulfur (S) elements in active materials, the "shuttle effect" caused by lithium polysulfide, and the growth of lithium dendrites impede the commercial development of Li-S batteries. As a crucial component of the battery, the separator plays a vital role in mitigating the shuttle effect caused by polysulfide. Traditional polypropylene, polyethylene, and polyimide separators are constrained by their inherent limitations, rendering them unsuitable for direct application in lithium–sulfur batteries. Therefore, there is an urgent need for the development of novel separators. This review summarizes the applications of different separator preparation methods and separator modification methods in lithium–sulfur batteries and analyzes their electrochemical performance. [ABSTRACT FROM AUTHOR]

In this review, the formation mechanism of NaPSs shuttling and their interaction with different battery components are introduced in detail, and recent advances and strategies for suppressing the shuttle effect of polysulfides are systematically discussed, which will point out the direction to design high-performance RT Na-S batteries. [Display omitted] • Room-temperature sodium-sulfur batteries are emerging as a promising next-generation energy storage system. • The efficient suppression of the shuttle effect is crucial to improve the battery cycling stability. • A comprehensive review targets the underlying mechanisms of shuttling behavior. Room-temperature sodium-sulfur (RT Na-S) batteries are considered as a promising next-generation energy storage system due to their remarkable energy density and natural abundance. However, the severe shuttling behavior of sodium polysulfides (NaPSs) significantly hinders their commercial visibility. Therefore, several strategies have been developed to tackle this issue, which is crucial to boosting the reaction kinetics of sulfur and enhancing the battery cycling stability. This review meticulously and comprehensively summarizes the various strategies employed by different components to inhibit the shuttling of NaPSs. First, we describe the working principles of RT Na-S batteries and the corresponding formation mechanism of the shuttle effect in detail. Subsequently, the latest advancements and techniques for alleviating the NaPSs shuttling are systematically examined from four perspectives: cathode, electrolyte, separator, and anode. Finally, this review presents an exhaustive analysis of the current challenges and future research prospects concerning the inhibition of the shuttle effect in RT Na-S batteries. [ABSTRACT FROM AUTHOR]

Schematic diagrams illustrating the principle of improving batteries performance by modifying separator with NSC/PP and MS@NSC/PP. [Display omitted] • Expanding aids in distributing metal sulfides uniformly via impregnation. • Carbon material covers large pores and improves interface impedance. • Composite separators anchor polysulfides and enhancing reaction kinetics. Lithium-sulfur (Li-S) batteries, renowned for high energy density and abundant sulfur reserves, are recognized as a research hotspot. However, the commercial implementing of Li-S batteries is confronted with scientific and technical challenges, including the shuttle effect resulting in low active material utilization, and slow reaction kinetics leading to poor cycle stability. To optimize the structure and composition of carbon composite materials based to meet the application requirements for long cycle life and high utilization of active substances has become the focus and difficulty. In this study, a composite separator MS@NSC/PP by coting nanosheet carbon (NSC) material loaded with amounts of metal sulfide (MS) was prepared via expansion technology and sulfurization impregnation. The combination of two processes greatly increases interaction area between MS@NSC and polysulfides and achieves uniform loading of MS, fully enhancing the mitigation of shuttle effect through strong chemical adsorption, and further hastening the conversion reaction of polysulfides deposited on the surface. Compared with NSC/PP and NiS 2 @NSC/PP separators, the batteries with CoS 2 @NSC/PP separator display a high initial discharge capacity of 1135 mAh g−1 at 0.2C, maintaining more improved cycle stability at 2C. [ABSTRACT FROM AUTHOR]

To mitigate lithium dissolution and polysulfide shuttle effect phenomena in high-energy lithium sulfur batteries (LISBs), a conductive, flexible, and easily modified polymer composite layer was applied on the anode. The polymer composite layer included polyaniline and functionalized graphite. The electrochemical behavior of LISBs was studied by galvanostatic charge/discharge tests from 1.7 to 2.8 V up to 90 cycles and via COMSOL Multiphysics simulation software. No apparent overcharge occurred during the charge state, which suggests that the shuttle effect of polysulfides was effectively prevented. The COMSOL Multiphysics simulation provided a venue for optimal prediction of the ideal concentration and properties of the polymer composite layer to be used in the LISBs. The testing and simulation results determined that the polymer composite layer diminished the amount of lithium polysulfide species and decreased the amount of dissolved lithium ions in the LISBs. In addition, the charge/discharge rate of up to 2.0 C with a cycle life of 90 cycles was achieved. The knowledge acquired in this study was important not only for the design of efficient new electrode materials, but also for understanding the effect of the polymer composite layer on the electrochemical cycle stability. [ABSTRACT FROM AUTHOR]

• A novel catalytic process for the disproportionation of dissolved polysulfides was discovered. • A pseudo-8-electron sulfur redox reaction mechanism was postulated. • The presence of dissolved polysulfides in the electrolyte was significantly reduced. • Efforts to mitigate the polysulfide shuttle phenomenon were successful. A catalytic pseudo-8-electron redox reaction of sulfur is achieved by facilitating the disproportionation of high-order polysulfide ions in a Li-Sulfur battery. Electrochemically generated polysulfide ions (S x 2-, where 3 < x < 7) undergo rapid disproportionation into elemental sulfur (S 8) and Li 2 S 2 , catalyzed by a bifunctional carbon host/catalyst. The overall catalytic redox reaction at the sulfur cathode is represented as S 8 + 8 L i + + 8 e ⇌ 4 L i 2 S 2. In contrast to physical or chemical confinement methods for polysulfide ions, this approach remediates the shuttle effect by swiftly converting soluble polysulfides in the electrolyte to elemental sulfur and insoluble Li 2 S 2 within the cathode matrix. As a result, the adverse chemical interaction between dissolved polysulfides and the Li anode is mitigated. [ABSTRACT FROM AUTHOR]

Highlights: Fe single atoms supported on porous carbon nanofiber are prepared by spatial confinement. The iron single atoms supported on porous nitrogen-doped carbon nanofibers (FeSAs-NCF) can promote the reversible conversion between aluminum polysulfides. The FeSAs-NCF can chemically anchor the polysulfides to suppress shuttle effect. Rechargeable aluminum–sulfur (Al–S) batteries have been considered as a highly potential energy storage system owing to the high theoretical capacity, good safety, abundant natural reserves, and low cost of Al and S. However, the research progress of Al–S batteries is limited by the slow kinetics and shuttle effect of soluble polysulfides intermediates. Herein, an interconnected free-standing interlayer of iron single atoms supported on porous nitrogen-doped carbon nanofibers (FeSAs-NCF) on the separator is developed and used as both catalyst and chemical barrier for Al–S batteries. The atomically dispersed iron active sites (Fe–N4) are clearly identified by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption near-edge structure. The Al–S battery with the FeSAs-NCF shows an improved specific capacity of 780 mAh g−1 and enhanced cycle stability. As evidenced by experimental and theoretical results, the atomically dispersed iron active centers on the separator can chemically adsorb the polysulfides and accelerate reaction kinetics to inhibit the shuttle effect and promote the reversible conversion between aluminum polysulfides, thus improving the electrochemical performance of the Al–S battery. This work provides a new way that can not only promote the conversion of aluminum sulfides but also suppress the shuttle effect in Al–S batteries. [ABSTRACT FROM AUTHOR]

In the effort to accelerate adsorption and catalytic conversion of lithium polysulfides (Li‐PSs) and suppress the shuttle effect of lithium‐sulfur batteries (LSBs), the Ti4O7 nanosheets/carbon material‐modified separator is successfully fabricated to reducing soluble Li‐PSs' crossover from cathode to anode. The catalyst of mesoporous Ti4O7 nanosheets with O−Ti−O units synthesized at low temperature shows both excellent conductivity and high surface area. The modified separator can serve as a diffusion barrier of Li‐PSs and catalyst for converting soluble low‐chain sulfides into insoluble ones and then remarkably enhance the sulfur utilization and electrochemical performance of the LSB. This work provides a feasible avenue in both design and synthesis of mesoporous catalyst materials for suppressing the shuttle effect of lithium‐sulfur batteries. [ABSTRACT FROM AUTHOR]

The commercialization of lithium-sulfur batteries (LSBs) has been hindered by the shuttle effect and slow sluggish conversion kinetics. This study developed MXene and Prussian blue analogue (PBA) heterostructures using an end-group-directed self-assembly strategy. MXene@PBA heterostructures were synthesized through layer-by-layer stacking and in situ growth of Mn-PBA, driven by the electrostatic interactions between Mn2+ and the polar terminal groups of MXene. The dual-metal synergistic adsorption of Mn2+ and Fe3+ within PBA framework significantly enhances both the adsorption capacity and cycling stability of the composite. Furthermore, the in-situ growth of PBA not only reinforces the structural integrity but also increases the number of active sites, mitigates the collapse of the accordion-like layered structure, alleviates volume expansion, and accelerates rapid ion diffusion. Theoretical calculations confirm the composite's superior adsorption capacity for Li polysulfides (LiPSs). As a S host, MXene@PBA facilitates the solid-liquid phase transformation of polysulfides, improving reaction kinetics and delivering exceptional electrochemical performance. MXene@PBA composite exhibited an initial discharge capacity of 1220 mAh g−1 at 0.1 C. Its cycle stability is equally remarkable, with a minimal decay rate of 0.062 % per cycle after 500 cycles at 0.5 C. The construction of these layered heterostructures as S hosts presents an effective strategy to mitigate the shuttle effect and enhance the reaction kinetics of LSBs. • MXene@PBA was successfully synthesized by an end-group-directed self-assembly strategy. • The synergistic effect of layered MXene and PBA significantly improved the shuttle effect. • MXene@PBA bi-directionally accelerates the solid-liquid phase transition of polysulfides and enhances reaction kinetics. • MXene@PBA@S anode exhibits excellent cycling stability in lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

The Lithium sulfur (Li-S) battery has a great potential to replace lithium-ion batteries due to its high-energy density. However, the "shuttle effect" of polysulfide intermediates (Li2S8, Li2S6, Li2S4, etc.) from the cathode can lead to rapid capacity decay and low coulombic efficiency, thus limiting its further development. Anchoring polysulfide and inhibiting polysulfide migration in electrolytes is one of the focuses in Li-S battery. It is well known that polar metal oxides-manganese oxides (MnO2) are normally used as an effective inhibitor for its polysulfide inhibiting properties. Considering the natural 1D tunnel structure, MnO2 with three kinds of typical tunnel-type were screened to study the effects of the tunnel size on the adsorption capacity of polysulfide. We found that MnO2 with larger tunnel sizes has stronger chemisorption capacity of polysulfide. It promotes the conversion of polysulfide, and corresponding cathode exhibits better cycle reliability and rate performance in the cell comparison tests. This work should point out a new strategy for the cathode design of advanced Li-S battery by controlling the tunnel size. [ABSTRACT FROM AUTHOR]

The detrimental shuttle of soluble species from cathode to anode inside battery, is a critical thorn limiting stability and reversibility of rechargeable battery. Herein, an ordered pore‐window of zeolite molecular sieve is employed to effectively block shuttle of soluble matters, and prepared zeolite powder into thin zeolite layer (5 µm thick) coated on celgard separator (zeolite@celgard) with flexible and grid‐scale fabrication features. External pressure is applied to press zeolite@celgard to reduce existed interparticle gaps among zeolite particles. The separation function toward soluble species and attached H2O scavenger role of zeolite@celgard are demonstrated via 1H/19F Nuclear Magnetic Resonance spectra, Inductive Coupled Plasma Emission Spectrometer and X‐Ray Photoelectron Spectroscopy results collected from Li/LiMn2O4 battery, time‐dependent in situ Raman tests in Li/S battery, and penetration experiments of redox mediator shuttle in Li/O2 battery. Replacing typically‐used celgard/glassfiber separators, a series of side reactions (active material outflowing, low coulombic efficiency, and anode corrosion) induced via shuttle of soluble species are addressed, resulting in battery performance improvement of Li/LiMn2O4, Li/S, and Li/O2 batteries. Both scientific hypothesis of utilizing pore‐size effect of zeolite for physically block soluble species, and cost‐effective, grid‐scale, and flexible zeolite‐based separators can be extended to other rechargeable battery systems based on flowing/soluble species. [ABSTRACT FROM AUTHOR]

The polyolefin separators commonly used in lithium-sulfur (Li-S) batteries are not able to withstand high temperatures and easily lead to thermal runaway and cause safety problems. In addition, the pore size of the polyolefin separator is too large to inhibit the shuttle effect of polysulfide. Herein, TiO 2 modified para-aramid nanofiber (TiO 2 /ANFs) composite separator for thermal runaway prevention and shuttle effect mitigation of lithium-sulfur batteries was designed and obtained. The TiO 2 /ANFs composite separators remained intact at 200 °C and showed excellent self-quenching characteristic. In addition, the TiO 2 /ANFs composite separators could inhibit the growth of lithium dendrites to a certain extent. Therefore, the TiO 2 /ANFs composite separators could prevent thermal runaway and had excellent safety. And TiO 2 could anchor the polysulfide, which could inhibit the shuttle effect. In addition, ionic conductivity had been greatly improved due to the addition of TiO 2 , which was conducive to high-flux lithium-ion transfer. In particular, 2-TiO 2 /ANFs composite separators had an average discharge specific capacity of 889.7mAhg−1 at 0.2C. Through density functional theory (DFT) calculation, the effective chemisorption mechanism of active sulfur and TiO 2 was deeply carried out. The result showed that TiO 2 could ensure the effective chemisorption of active sulfur, resulting in the long-term cycling stability. [Display omitted] • TiO 2 modified para-aramid nanofiber (TiO 2 /ANFs) composite separators with high safety and performance was obtained and used as the separators for lithium sulfur batteries. • The TiO 2 /ANFs composite separators was prepared by blending and phase transformation method. • The TiO 2 /ANFs composite separators remained intact at 200 °C and showed excellent self-quenching characteristic. • The TiO 2 /ANFs composite separators had high ionic conductivity and excellent cycling performance. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries exhibit great potential as one of the most promising energy storage devices due to their high theoretical energy density and specific capacity. However, the shuttle effect of the soluble polysulfide intermediates could lead to a severe self-discharge effect that hinders the development of lithium-sulfur batteries. In this paper, a battery separator has been prepared based on NiFe2O4/Ketjen Black (KB) modification by a simple method to solve the shuttle effect and improve the battery performance. The as-modified separator with the combination of small-size KB and NiFe2O4 nanoparticles can effectively use the physical and chemical double-layer adsorption to prevent polysulfide from the shuttle. Moreover, it can give full play to its catalytic effect to improve the conversion efficiency of polysulfide and activate the dead sulfur. The results show that the NiFe2O4/KB-modified separator battery still maintains a discharge capacity of 406.27 mAh/g after 1000 stable cycles at a high current density of 1 C. Furthermore, the coulombic efficiency remains at 99%, and the average capacity attenuation per cycle is only 0.051%. This simple and effective method can significantly improve the application capacity of lithium-sulfur batteries. [ABSTRACT FROM AUTHOR]

The success of lithium–sulfur batteries will reduce the expected Co, Ni resource challenges from the wide adoption of lithium‐ion batteries. Unfortunately, the shuttle effect of soluble polysulfides brings many problems. Anchoring or blocking polysulfides on the cathode side using functional separators is the dominant strategy for addressing this. However, the blocked polysulfides gradually aggregate on the separator to form the so‐called "dead sulfur" and withdraw from cycling. Herein, a multipurpose separator is proposed that enables catalytic activation of the blocked polysulfides to prevent the formation of "dead sulfur", and contribute to capacity. The multifunctionality is supported by montmorillonite (MMT) that provides sufficient channels for lithium‐ion transport, and selenium‐doped sulfurized‐polyacrylonitrile (Se0.06SPAN) that catalyzes conversion of "dead sulfur" and simultaneously contributes capacity. The theoretical calculations reveal Se0.06SPAN/MMT has a low migration barrier for Li+ and a low decomposition barrier for Li2S, facilitating the conversion and minimizing "dead sulfur". Consequently, the Li–S battery with the Se0.06SPAN/MMT@PP (polypropylene) separator shows a low fading rate of 0.034% during 1000 cycles and achieves a super‐high areal capacity (33.07 mAh cm–2) under high sulfur loading (26.75 mg cm–2) and lean electrolyte conditions (4.5 µL mg–1). Moreover, the multipurpose separator has encouraging performance in stability, flexibility, and sustainability. [ABSTRACT FROM AUTHOR]

The commercializaton of lithium-sulfur (Li-S) batteries faces several bottlenecks, and the major two of which are the shuttle effect of polysulfides and the wild growth of Li dendrites, responsible for fast capacity decay and severe safety issues. As an essential component of Li-S batteries, the structure and properties of the separators are closely related to the above problems, and the exploration of multifunctional separators is highly sought-after. Herein, an integrated separator composited of defective graphene and polyimide (DG-PI) was innovatively fabricated by electrospinning combined with the laser-induced carbonization strategy. The all-in-one compact architecture with well-interconnected channels shows superior mechanical and thermal stability and wettability. More importantly, the PI nanofibers containing N–/O–functional groups can induce the uniform deposition of lithium on the anode surface, while the DG framework with abundant pentagonal/heptagonal rings and vacancies can strongly trap polysulfides and accelerate polysulfide transformation on the cathode side. The strong chemical interaction between the insulative PI layer and the conductive DG layer modulates the surface charge distribution of each other, leading to more prominent contributions to restraining lithium dendrites and shuttle effect. Therefore, the Li-S batteries based on the integrated DG-PI separators afford an excellent performance in protecting lithium anode (stable cycles of 200 h at 5 mA·cm−2) and good cycling stability with a low capacity decay of 0.05% per cycle after 700 cycles at 1 C. This work offers a new design concept of multifunctional Li-S battery separators and broadens the application scope of laser micro-nano fabrication technology. [ABSTRACT FROM AUTHOR]

One of the major issues limiting the practical application of lithium-sulfur (Li-S) batteries is that the sluggish redox kinetics of polysulfide intermediates exacerbate the unavoidable "shuttle effect", which causes low sulfur utilization, rapid capacity fade, and anode corrosion. Herein, we firstly add a novel type of electrolyte additive, biological reagents dithiothreitol (DTT), into the traditional electrolyte of Li-S batteries to suppress the "shuttle effect". DTT is able to be stabilized in original electrolyte system at room temperature and selectively slice the -S-S- bonds of polysulfides. The electrochemical studies reveal DTT significantly accelerate the reactions kinetic in cycle process and thus effectively inhibit the shuttling of polysulfides. As a result, the hierarchical porous carbon/S cathode using the electrolyte with 10 g L−1 DTT exhibits a high rate performance (570 mA h g−1 improved from 317 mAh g−1 at 3 C), a high initial discharge capacity (808 mAh g−1 at 0.5 C), and a superior cyclic stability (a low capacity fading rate of 0.025% per cycle over 500 cycles at 2 C). This strategy provides a new direction for achieving high energy density Li-S batteries and thus facilitating their practical application from the point of improving the kinetic sluggishness by electrolyte additive. • The effect of DTT additive in Li-S batteries is investigated for the first time. • DTT is stable in electrolyte and can slice -S-S- bonds of polysulfides. • DTT accelerates discharge reactions kinetic and inhibits the "shuttle effect". • An appropriate amount of DTT additive improves electrochemical performances. [ABSTRACT FROM AUTHOR]

[Display omitted] • SnP 3 as an anchoring material can effectively anchor soluble LiPSs. • The rate limiting step has changed, indicating that SnP 3 can catalyze the conversion of polysulfides and prevent their accumulation. • Lower decomposition and diffusion barriers of Li 2 S can improve utilization ratio of sulfur and cycle performance of Li-S batteries. The problems of the shuttle effect and sluggish transformation kinetics of lithium polysulfides (LiPSs) severely inhibit the practical application of Li-S batteries. Exploring anchoring materials with catalytic properties is an effective way to overcome these obstacles. In this paper, the electrochemical performance of SnP 3 monolayer as an anchoring material is explored by using first-principles calculations. SnP 3 monolayer can effectively anchor soluble LiPSs under vacuum and solvent conditions, and provides abundant adsorption sites for anchoring multiple LiPSs. Importantly, the rate-limiting step has changed to the conversion of Li 2 S 8 to Li 2 S 6 , suggesting that the monolayer can facilitate the conversion of LiPSs and inhibit their accumulation in the electrolyte. Furthermore, lower decomposition and diffusion barriers of Li 2 S effectively inhibit the volume expansion of Li-S batteries. Thus, SnP 3 monolayer becomes a promising anchoring material with suitable catalytic properties. This work demonstrates the feasibility of SnP 3 monolayer as an anchoring material and expands the membership of phosphide family for applications in the field of Li-S batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Room temperature sodium-sulfur battery has high theoretical specific energy and low cost, so it has good application prospect. However, due to the disadvantageous reaction between soluble intermediate polysulfides and sodium anode, the capacity drops sharply, which greatly limits its practical application. In recent years, various strategies have been formulated to address the problem of polysulfides dissolution. This perspective article provides an overview of the research progress on research progress of novel cathode materials, multifunctional host, new electrolyte systems and modified separator/interlayer/anode. The challenge and prospect of the advanced strategies to suppress the polysulfides shuttle for long-life and high-efficiency room temperature sodium-sulfur batteries are proposed. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are considered the most promising energy storage systems due to their high specific capacity and energy density. However, the practical application of lithium-sulfur batteries has been hampered by capacity loss due to the shuttle effect and serious safety issues due to the flammability and shrinkage of commercial diaphragms at high temperatures. Herein, we designed a separator by adding ZIF-8 nanoparticles to aramid nanofibers named ZIF-8/ANF. ANF has high flame retardant property and high mechanical strength to prevent separators failure at high temperature, preventing lithium dendrites from punctured separators and causing short circuit. ZIF-8 has the porous structure, while exposing abundant metal nodes acting as active sites, which can effectively adsorb polysulfides and inhibit the shuttle effect. As a result, the Li-S batteries with ZIF-8/ANF separators exhibit high specific discharge capacity and cycle performance. The Li-S batteries show a high initial specific capacity of 1178.3 mAh g−1 at 0.1 C and 525.9 mAh g−1 after 400 cycles. In addition, they also exhibit discharge capacity is 825.6 mAh g−1 at 0.2 C with the loading of 3.5 mg cm−2. This work offers a guidance for safe and high-performance Li-S batteries. [Display omitted] • A ZIF-8 modified aramid nanofiber separator was designed. • ZIF-8/ANF separator has high flame retardant properties and high mechanical strength. • ZIF-8 has abundant metal nodes as active sites which can effectively adsorb polysulfides. • The Li-S batteries with ZIF-8/ANF separator exhibit high specific discharge capacity and cycle performance. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) have gained intense research enthusiasm due to their high energy density. Nevertheless, the 'shuttle effect' of soluble polysulfide (a discharge product) reduces their cycling stability and capacity, thus restricting their practical application. To tackle this challenging issue, we herein report a sulfonated covalent organic framework modified separator (SCOF-Celgard) that alleviates the shuttling of polysulfide anions and accelerates the migration of Li+ ions. Specifically, the negatively charged sulfonate can inhibit the same charged polysulfide anion through electrostatic repulsion, thereby improving the cycle stability of the battery and preventing the Li-anode from being corroded. Meanwhile, the sulfonate groups may facilitate the positively charged lithium ions to pass through the separator. Consequently, the battery assembled with the SCOF-Celgard separator exhibits an 81.1% capacity retention after 120 cycles at 0.5 C, which is far superior to that (55.7%) of the battery with a Celgard separator. It has a low capacity degradation of 0.067% per cycle after 600 cycles at 1 C, and a high discharge capacity (576 mAh g−1) even at 2 C. Our work proves that the modification of a separator with a SCOF is a viable and effective route for enhancing the electrochemical performance of a LSB. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Y(OH) 3 host is proposed and prepared for lithium sulfur batteries. • Shuttle effect of polysulfides is suppressed by the pore channel restriction. • Polysulfides are anchored by synergistic effect of lithium bond and sulfur bond. • Y(OH) 3 /S cathode exhibits improved electrochemical performance. Rechargeable lithium–sulfur (Li–S) batteries reveal promising prospect as high energy storage systems because of the extraordinary theoretical specific energy density. However, the shuttle effect and sluggish reaction kinetics of polysulfides hamper the commercialization applications of high energy density Li-S batteries. Herein, a novel and efficient sulfur host material of yttrium hydroxide (Y(OH) 3) has rationally been achieved for Li–S batteries. Y(OH) 3 host not only suppress shuttle effect of polysulfides by physical confinement and chemisorption, but also decline Li 2 S nucleation and deposition reaction barriers and expedite chemical reaction kinetics. Consequently, the prepared Y(OH) 3 /S cathodes achieve a high initial specific capacity of 1295 mAh g−1 at 0.1 C and improved cycling stability with a low capacity decay rate of 0.019% per cycle over 1000 cycles at 2.0 C. The enhanced performances confirm a potential host material for facilitating practical implementation of Li–S batteries. [ABSTRACT FROM AUTHOR]

• The Porous-layered GO@S/SFAC composites were designed and synthesized. • The GO@S/SFAC composites inhibit the dissolution and shuttling of polysulfides. • The GO@S/SFAC composites have good electrochemical performance. This study designed and synthesized porous-layered GO@S/SFAC composites to solve the capacity fading problem of lithium–sulfur batteries, which is caused by the shuttle effect. In the composites, the inner porous sisal fiber activated carbon (SFAC) provides a framework for accommodating active sulfur as a host; The outer layered graphene oxide (GO) restricts the dissolution and migration of polysulfides through physical confinement and chemical adsorption. As the cathode of the lithium–sulfur battery, the initial discharge specific capacity of the GO@S/SFAC composites is 1364 mAh g−1, and the discharge specific capacity is maintained at 658 mAh g−1 after 100 cycles at 0.1C. Compared with the sulfur cathode, the electrochemical performance is significantly improved and the shuttle effect is effectively suppressed. [ABSTRACT FROM AUTHOR]

Abstract Lithium–sulfur (Li–S) batteries have attracted significant attention in the realm of electronic energy storage and conversion owing to their remarkable theoretical energy density and cost‐effectiveness. However, Li–S batteries continue to face significant challenges, primarily the severe polysulfides shuttle effect and sluggish sulfur redox kinetics, which are inherent obstacles to their practical application. Metal‐organic frameworks (MOFs), known for their porous structure, high adsorption capacity, structural flexibility, and easy synthesis, have emerged as ideal materials for separator modification. Efficient polysulfides interception/conversion ability and rapid lithium‐ion conduction enabled by MOFs modified layers are demonstrated in Li–S batteries. In this perspective, the objective is to present an overview of recent advancements in utilizing pristine MOF materials as modification layers for separators in Li–S batteries. The mechanisms behind the enhanced electrochemical performance resulting from each design strategy are explained. The viewpoints and crucial challenges requiring resolution are also concluded for pristine MOFs separator in Li–S batteries. Moreover, some promising materials and concepts based on MOFs are proposed to enhance electrochemical performance and investigate polysulfides adsorption/conversion mechanisms. These efforts are expected to contribute to the future advancement of MOFs in advanced Li–S batteries.

• A metallic cobalt-doped ZSM-5 zeolite with extra-framework Li+ is innovatively constructed. • The functionalized zeolite-modified separator endows lithium–sulfur batteries with fast redox conversion and low shuttle effect. • Superior cyclic stability, excellent rate capability, and negligible self-discharge behavior are achieved. Lithium–sulfur (Li–S) batteries are among the most promising next-generation rechargeable battery systems because of their high theoretical energy density and low cost. Nevertheless, the notorious shuttle effect of polysulfides and poor redox kinetics significantly limit their practical applications. Herein, a metallic cobalt-doped ZSM-5 zeolite with extra-framework Li+ is constructed to inhibit the migration of polysulfides and simultaneously enhance their conversion kinetics via a separator coating strategy. The ZSM-5 zeolite possessing a sub-nanometer channel structure acts as an ionic sieve, and effectively suppresses the undesired polysulfide migration by spatial constraint. The negatively charged zeolite framework with Li+ as counterions helps to facilitate the fast Li+ transport. More importantly, Co dopants further strengthen the interaction with polysulfides and work as active sites to improve the kinetics of sulfur redox reactions, which is verified by theoretical calculations and experiments. As expected, a Li–S battery employing the modified separator delivers superior long-term cyclic stability (only 0.04% capacity decay per cycle over 500 cycles at 1.0 C) and excellent rate capability (706 mAh g−1 at 3.0 C). In addition, the stable operation of an assembled Li–S pouch cell under various bending angles demonstrates its feasibility in practical applications. This work offers a new insight into the design of advanced separator modifiers for high-performance Li–S batteries. [ABSTRACT FROM AUTHOR]

Lithium−sulfur (Li−S) batteries are ideal energy storage devices due to their high energy density (2600 Wh kg−1), but polysulfide shuttling and lithium dendrite growth seriously preclude their practical application. Herein, a multifunctional layer composed of MnO, MnWO 4 and carbon black (CB) is constructed to modify the polypropylene separator (MnO-MnWO 4 /CB@PP) of Li−S batteries. The MnO-MnWO 4 /CB layer possesses the ability to adsorb polysulfides through physical and chemical adsorption mechanisms, as well as catalyze their conversion. Results show that the adsorption-catalysis characteristic of MnO-MnWO 4 /CB enhances the capture capability for polysulfides to suppress its shuttling. Moreover, it acts as a buffer layer, facilitating the parallel electrodeposition of Li and inhibiting the growth of Li dendrite. As a result, the Li/Li symmetrical cell with MnO-MnWO 4 /CB@PP enables durable Li plating/stripping over 8000 h at 1.0 mA cm−2 with a capacity of 1.0 mAh cm−2. In addition, the Li−S battery with this modified separator demonstrates a competitive initial capacity of 1527.7 mAh g−1 at 0.2 C and a capacity retention of 80.8% after 1000 cycles at 2.0 C. This work presents an effective and straightforward approach for designing separator of Li−S battery. [Display omitted] • MnO-MnWO 4 /CB interlayer contributes to preventing the shuttle of polysulfides. • MnO-MnWO 4 /CB interlayer can inhibit the growth of lithium dendrite. • MnO-MnWO 4 /CB-modified separator shows the stable cycling performance in Li−S batteries. [ABSTRACT FROM AUTHOR]

Alternatives of commercial lithium‐ion batteries (LIBs) have drawn huge attention due to the large demand of energy storage systems and the lack of resources for traditional LIBs. Promising candidates include but are not limited to Li‐S batteries, organic batteries and flow batteries. However, the dissolution of active materials and the consequent shuttle effect, as one of the main challenges in these candidates, always leads to significant capacity loss and poor cycling life. The rising two‐dimensional (2D) materials, with well‐defined structures and attractive physical and chemical properties, provide a new vision to solve these problems via suppressing the shuttle of the dissolved active materials. Herein, we present a minireview on the advances and perspectives of 2D materials as ionic sieves for inhibiting the shuttle effect in batteries. [ABSTRACT FROM AUTHOR]

Lithium–Sulfur Batteries (LSBs) have attracted significant attention as promising next‐generation energy storage systems. However, the commercial viability of LSBs have been hindered due to lithium polysulfides (LiPSs) shuttle effect, resulting in poor cycling stability and low sulfur utilization. To address this issue, herein, the study prepares a sulfur host consisting of micro/mesopore‐enriched activated carbonaceous materials with ultrahigh surface area using organic pigment via facile one‐step activation. By varying the proportion of chemical agent, the pore size and volume of the activated carbonaceous materials are manipulated and their capabilities on the mitigation of LiPSs shuttle effect are investigated. Through the electrochemical measurements and spectroscopic analysis, it is verified that structural engineering of carbon hosts plays a pivotal role in effective physical confinement of LiPSs, leading to the mitigation of LiPSs shuttle effect and sulfur utilization. Additionally, nitrogen and oxygen‐containing functional groups originated from PR show electrocatalytic activation sites, facilitating LiPSs conversion kinetics. The approach can reveal that rational design of carbon microstructures can improve trapping and suppression of LiPSs and shuttle effect, enhancing electrochemical performance of LSBs. [ABSTRACT FROM AUTHOR]

Ferroelectricity has an excellent reversible polarization conversion behavior under an external electric field. Herein, we propose an interesting strategy to alleviate the shuttle effect of lithium–sulfur battery by utilizing ferroelectric metal–organic framework (FMOF) as a host material for the first time. Compared to other MOF with same structure but without ferroelectricity and commercial carbon black, the cathode based on FMOF exhibits a low capacity decay and high cycling stability. These results demonstrate that the polarization switching behaviors of FMOF under the discharge voltage of lithium–sulfur battery can effectively trap polysulfides by polar–polar interactions, decrease polysulfides shuttle and improve the electrochemical performance of lithium–sulfur battery. [ABSTRACT FROM AUTHOR]

Li-S batteries are widely studied due to their superior theoretical energy density. However, the "shuttle effect" on the cathode and the unstable Li metal anode hinder their practical application. During cycling, the "shuttle effect" leads to severe self-discharge and accelerates the capacity decay. Moreover, the shuttled polysulfides aggravate the growth of dendrites and the loss of Li, causing a low Coulombic efficiency. Considering electrolyte plays a crucial role in the polysulfides solvation behavior and solid electrolyte interphase (SEI)-formation process, a well-designed electrolyte is required. Here, we report a local high-concentration electrolyte for Li-S batteries. This electrolyte is prepared by adding "diluent" 1,1,2,2-tetrafluoroethyl methyl ether (TME) to the conventional electrolyte. The reduction of free solvent in the Li-ion solvation sheath suppresses the dissolution of the polysulfides, and more anion-derived SEI can be formed. Our work simultaneously restrains the "shuttle effect" of the cathode and builds a stable SEI on the anode to protect the Li metal. Without any LiNO3 additive, the average Coulombic efficiency of the Li anode can reach 98.87% after 120 cycles, and Li-S batteries with superior capacity retention of 60% after 400 cycles at 0.5 C can be achieved. [ABSTRACT FROM AUTHOR]

Functional separators have become one of the hot topics for improving the electrochemical performance of the Li-S batteries. This is mainly due to the positive effect of the functional separators for efficiently inhibiting the shuttle effect of soluble polysulfide. Based on this reason, MoS 2 coated separators are prepared and used as an efficient barrier for inhibiting shuttle effect in the Li-S battery. The as-prepared MoS 2 coated separators exhibit perfect wettability. Therefore, the whole battery could achieve rapid Li-ion diffusion. Besides, the metal sulfide MoS 2 provides chemical adsorption for the polysulfide. As a result, comparing with the pristine separator, the Li-S battery that used MoS 2 coated separator shows higher specific capacity and more excellent cycle stability. [ABSTRACT FROM AUTHOR]

In this work, we deposited a nanometric layer of platinum (40 nm thick) on a standard propylene/polypropylene Celgard separator 3501 by plasma sputtering, and studied the effect of this thin layer when in contact with a lithium metal anode in a Li-S battery. The platinum-coated Celgard slowed down the shuttle effect at low current density (C/10) compared to standard Celgard and led to an increase in capacity retention at higher current density (C/2). In addition, the polarization was reduced with a platinum separator in a Li-Li symmetric cell after 500 h. • 40 nm Platinum nanolayer protects lithium metal surface in Li-S batteries. • Shuttle effect is reduced whit platinum interlayer. • Discharge capacity of Lithium-sulfur battery is improved with platinum interlayer. • No Li-Pt alloys are formed. • Platinum interlayer is more performant than gold interlayer. [ABSTRACT FROM AUTHOR]

The shuttling of soluble polysulfides between electrodes is the main factor leading to the rapid capacity fading of Li-S batteries. A functional rich amine porous organic polymer/acetylene black-polypropylene (RAPOP/AB-PP) separator was prepared using a straightforward coating modification of the commercial PP separator to improve the electrochemical performance of Li–S batteries. Electrochemical impedance spectroscopy and discharge/charge tests using S electrodes as research electrodes determined that the abundant amount of imine groups of RAPOPs exhibited strong anchoring properties toward Li polysulfides. The tests also confirmed that the RAPOP/AB-PP separator could effectively inhibit the shuttling of polysulfides. During discharge, the modified separator adsorbed the polysulfides from the electrolyte on the surface of the S electrode and formed a thin layer of Li polysulfide. In addition, this accumulation layer inhibited the diffusion of Li polysulfide through the separator toward the Li electrode. The initial and 800 cycle discharge capacity densities of the RAPOP/AB-PP-1.7 membrane were 1322 and 897 mAh g−1 (at the current density of 0.2 mA cm−2), respectively which were much higher than the 1121 and 481 mAh g−1 corresponding values for the polypropylene separator. In addition, the RAPOP/AB-PP separator possessed a higher electrolyte uptake capacity (114%) than the PP separator (88%). Outstanding electrolyte wettability caused the ion conductivity (1.08 × 10−1 mS cm−1) of the RAPOP/AB-PP membrane to be much higher than that of the PP separator (1.19 × 10−2 mS cm−1). Therefore, the excellent electrochemical performance of the RAPOP/AB-PP separator could be ascribed to the polar RAPOP/AB coating not only alleviating the shuttle effect but also facilitating Li+ ions migration. [ABSTRACT FROM AUTHOR]

Sodium-sulfur batteries show great potential for storing large amounts of energy due to their ability to undergo a double electron-redox process, as well as the plentiful abundance of sodium and sulfur resources. However, the shuttle effect caused by intermediate sodium polysulfides (Na 2 S n) limits their performance and lifespan. To address this issue, here we propose using Hf 3 C 2 T 2 and Zr 3 C 2 T 2 (T = F, O), two functionalized MXenes, as cathode additives to suppress the shuttle effect. By using density-functional theory calculations, we investigate nature of the interactions between Na 2 S n and MXene, such as the strength of adsorption energy, the electronic density of states, the charge exchange, and the dissociation energy of the Na 2 S molecule. Our findings show that both Hf 3 C 2 T 2 and Zr 3 C 2 T 2 systems inhibit the shuttle effect by binding to Na 2 S n with a binding energy stronger than the commonly used electrolyte solvents. These MXenes retain their metallicity during this process and the decomposition barrier for Na 2 S n on the oxygen-functionalized MXenes gets reduced which enhances the electrochemical process. Among the MXene systems studied, Zr 3 C 2 O 2 shows the best performance in suppressing the shuttle effect and catalyzing the electrochemistry process and, thus, increasing the battery's reversible capacity and lifespan. [Display omitted] • DFT study of suppression of shuttle effect in NaSBs proposed new cathode additives. • 4 MXenes (Hf 3 C 2 T x , Zr 3 C 2 T x , T = F/O) were considered as cathode additives. • E bind of Na 2 S n with MXenes stronger than electrolyte so to prevent shuttle effect. • They have moderate potential barrier for easy dissociation of Na 2 S during charging. • Zr 3 C 2 O 2 MXenes found to be the best for performance and lifetime of the NaSBs. [ABSTRACT FROM AUTHOR]

Chemical anchoring and facilitated transformation of polysulfides by polar titanium nitride nanoparticles and uniform distribution of sulfur by non-polar graphene showed efficient cooperative interactions for lithium–sulfur batteries, which contributed to the enhanced electrochemical performance of a high initial discharge capacity of 1412 mA h g−1 (0.2 C) and long-term cyclability. [ABSTRACT FROM AUTHOR]

Inspired by hydrophobic interface, a novel design of "polysulfide‐phobic" interface was proposed and developed to restrain shuttle effect in lithium–sulfur batteries. Two‐dimensional VOPO4 sheets with adequate active sites were employed to immobilize the polysulfides through the formation of a V−S bond. Moreover, owing to the intrinsic Coulomb repulsion between polysulfide anions, the surface anchored with polysulfides can be further evolved into a "polysulfide‐phobic" interface, which was demonstrated by the advanced time/space‐resolved operando Raman evidences. In particular, by introducing the "polysulfide‐phobic" surface design into separator fabrication, the lithium–sulfur battery performed a superior long‐term cycling stability. This work expands a novel strategy to build a "polysulfide‐phobic" surface by "self‐defense" mechanism for suppressing polysulfides shuttle, which provides new insights and opportunities to develop advanced lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are extremely attractive because of their high theoretical capacities, energy densities, and cost-effectiveness, as well as the environmental friendliness of elemental sulfur. However, the commercialization of Li-S batteries is impeded by fast capacity fading and harsh self-discharge. To overcome these issues, effort has been dedicated to improving performance by designing the electrode structure and composition, which is often expensive and complex. In this study, modification of the separator by a combination of commercial titanium monoxide and multiwall carbon nanotubes (TiO/MWCNTs) was first designed, which is a low-cost and simple preparation process. The cooperative effect of TiO and MWCNTs capacitates the feedback of the Li-S cell with a relatively high premier discharge capacity of 1527.2 mAh g−1, and excellent cycling stability is obtained up to 1000 cycles at 0.5 C with a negligible fading rate of 0.057% per cycle. And the self-discharge behavior was improved obviously. When the time of rest was extended to 96 h, the capacity attenuation of the cell with the TiO/MWCNT coating was only 12.4%. The use of a TiO/MWCNT-coated separator is a feasible method for the commercial success of high-performance Li-S batteries. Image 1 • TiO/MWCNT composite is firstly used to modify the separator of Li-S battery. • High density of oxygen and titanium vacancies of TiO is benefit for adsorbing LiPSs. • MWCNT network as a physical barrier improves the conductivity of the separator. • The strong adsorption of TiO/MWCNT suppress the shuttle effect of Li-S battery. [ABSTRACT FROM AUTHOR]

A modified solution method was applied to synthesize cubic garnet solid-state electrolyte Li 7 La 3 Zr 2 O 12 (LLZO) and Li 6.45 Ca 0.05 La 2.95 Ta 0.6 Zr 1.4 O 12 (LCLTZO). The synergetic doping of Ca and Ta is found to induce the formation of cubic LCLZTO with high ionic conductivity of 4.03 × 10 −4  S cm −1 while LLZO without substitution exhibits tetragonal phase with low conductivity. A Li-S cell with sulfur cathode and as-prepared LCLTZO solid electrolyte “separator” was conducted to deliver large initial discharge capacity of 1090 mAh g −1 with high initial Coulombic efficiency up to 92%. Cell with LCLTZO also exhibited better cycling performance at 0.2 C and extremely high Coulombic efficiency (close to 100%) than the cell without solid electrolyte. Better rate performance was also achieved at lower rate (0.2 C, 0.5 C and 1 C) by cell with LCLTZO although it lost advantages at higher rate of 2 C and 5 C due to the limitation of ionic conductivity of LCLTZO. Energy dispersive X-ray spectroscopy (EDS) provided direct evidence that LCLTZO solid electrolyte greatly suppressed the shuttle effect generated by polysulfides. The electrochemical impedance spectroscopy was applied to discuss the difference between cells with and without LCLTZO during the discharge process. Charge transfer reaction referred to soluble polysulfides was found to be slower in cell with LCLTZO than that in cell without solid electrolyte. [ABSTRACT FROM AUTHOR]

Rapid capacity fade and untimely failure caused by the infamous "shuttle effect" prevents the commercialization of Lithium-sulfur batteries (LSB). In this work, lead zirconate titanate (PZT) nanofibers have been employed as polysulfide immobilizer in LSB. Ferroelectric materials possess a unique domain structure where each individual domain carries a dipole moment. The dipole-dipole interaction between the domains of the ferroelectric PZT nanofibers and polysulfides inhibits the diffusion of polysulfides from the cathode. In addition to electrostatic interactions, the 1-dimensional nanofibers with large specific surface area are accompanied by lithiophilic and sulfiphilic heteroatoms which act as anchoring points for chemically binding the polysulfides. Moreover, the enhanced wettability of the electrode arising from the favorable affinity of PZT nanofibers towards the electrolyte along with lithiophilic heteroatoms aids the diffusion of Lithium-ions. Briefly, the synergy of physical and chemical interaction of PZT nanofibers towards the polysulfide species is found to mitigate the shuttle effect and improve electrochemical performance of LSB. Further, a promising long-term cycling over 200 cycles for LSB cell with PZT interlayer is observed with 98% Coulombic efficiency and slow fade rate of 0.08% per cycle. [Display omitted] • PZT nanofibers are prepared by a simple electrospinning technique. • Lithium-sulfur cell with PZT interlayer exhibits excellent capacity retention. • PZT nanofibers promotes the diffusion of Lithium-ions. • Good cycling performance is achieved with PZT interlayer at higher C-rate. [ABSTRACT FROM AUTHOR]

The commercialization of Li–S batteries has been seriously hampered by the infamous "shuttle effect" of soluble lithium polysulfide intermediates (LiPSs, Li 2 S x , 4 ≤ x ≤ 8) and sluggish sulfur species conversion kinetics. In this work, vinyl ferrocene and styrene were copolymerized onto a polypropylene (PP) separator to prevent LiPS shuttling based on the electrostatic and orbital interactions between ferrocene and LiPSs, which increased the reactivity of LiPSs. Therefore, the "shuttle effect" can be successfully suppressed by a separator that combines thermodynamic anchoring and kinetic acceleration for LiPSs. [Display omitted] • Ferrocene was introduced onto the PP separator to retard the "shuttle effect" of LiPSs based on the electrostatic and orbital interactions between ferrocene and LiPSs. • By combining thermodynamic anchoring and kinetic acceleration for LiPSs, the "shuttle effect" can be greatly suppressed. • Ferrocene can spontaneously anchor the dissolved LiPSs thermodynamically. • Orbital interaction is utilized to increase the reactivity kinetically. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)