Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two crit...Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two critical challenges,i.e.,zinc dendrite growth and polyiodide shuttle effect,severely impede their commercial viability.To conquer these limitations,this study develops a multifunctional separator fabricated from straw-derived carboxylated nanocellulose,with its negative charge density further reinforced by anionic polyacrylamide incorporation.This modification simultaneously improves the separator’s mechanical properties,ionic conductivity,and Zn^(2+)ion transfer number.Remarkably,despite its ultrathin 20μm profile,the engineered separator demonstrates exceptional dendrite suppression and parasitic reaction inhibition,enabling Zn//Zn symmetric cells to achieve impressive cycle life(>1800 h at 2 m A cm^(-2)/2 m Ah cm^(-2))while maintaining robust performance even at ultrahigh areal capacities(25 m Ah cm^(-2)).Additionally,the separator’s anionic characteristic effectively blocks polyiodide migration through electrostatic repulsion,yielding Zn-I_(2) batteries with outstanding rate capability(120.7 m Ah g^(-1)at 5 A g^(-1))and excellent cyclability(94.2%capacity retention after 10,000 cycles).And superior cycling stability can still be achieved under zinc-deficient condition and pouch cell configuration.This work establishes a new paradigm for designing high-performance zinc-based energy storage systems through rational separator engineering.展开更多
A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface...A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property.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
Nowadays, the Multi-Shuttle and Multi-Station Transportation System (MMTS)<span><span><span style="font-family:;" "=""> is one of the most interesting research topics in many...Nowadays, the Multi-Shuttle and Multi-Station Transportation System (MMTS)<span><span><span style="font-family:;" "=""> is one of the most interesting research topics in many fields of industries. It is an effective solution to reduce unexpected accidents that occur during transportation as well as increase productivity in manufacturing. The aim of this paper is to introduce the controller design for the MMTS which is built in our BK-Recme BioMech Lab at Ho Chi Minh City University of Technology (VNU-HCM), Viet Nam. Based on the design of this system, the control algorithms will be conducted to check the operation of the whole system. To evaluate the feasibility and effectiveness of this model, we design a series of random instances for different quantities of nodes as well as the different quantities of shuttles. Our system includes 4 stations and 6 shuttles which are assembled in the serial chain system. However, the number of stations and number of shuttles can be expanded to any desired ones which are based on the requirement of the industries. In this paper, we mainly focus on the controller design of this system to make it operate in an effective way that the goods will be transported and delivered to the target station as fast as possible. In order to solve the large</span></span></span><span><span><span style="font-family:;" "="">-</span></span></span><span><span><span style="font-family:;" "="">scale instances and realistic transport prob<span>lems, we propose three algorithms for three progresses as shuttles calling</span>, path reading and shuttles communicating. The shuttles calling is to decide which <span>shuttle should be called to the star</span></span></span></span><span><span><span style="font-family:;" "="">t</span></span></span><span><span><span style="font-family:;" "="">-node. Path reading to determine the shortest</span></span></span><span><span><span style="font-family:;" "=""> <span>way to go from start-node to end-node. Finally, shuttles communicating,</span> which allow one shuttle to interact with the next shuttles so we have a loop of orders (shuttle 1 to shuttle 2;shuttle 2 to shuttle 3;etc</span></span></span><span><span><span style="font-family:;" "="">.</span></span></span><span><span><span style="font-family:;" "="">;shuttle n-1 to shuttle n). This proposes solution can help us to solve the huge numbers of shuttles <span>and stations in the system. The specific result of this study is applying</span> Dijkstra’s algorithm to propose an algorithm that allows handling a transportation system without caring about the number of shuttles as well as the number of stations for the closed-loop path. Several test problems are carried out in order to check the feasibility and the effectiveness of our purposed control algorithm.</span></span></span>展开更多
Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells （DSSCs）. The DSSCs incorporating ...Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells （DSSCs）. The DSSCs incorporating tris（1,10-phenanthroline）eobalt（Ⅱ/Ⅲ）-based redox elec- trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the w-conjugated spacers of organic dyes upon the photovoltage and photocur- rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination.展开更多
Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dend...Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dendrites formation and polysulfide shuttle effect are two major challenges that limit the commercialization of Li-S batteries.Here we design a facile bifunctional interlayer of gelatin-based fibers(GFs),aiming to protect the Li anode surface from the dendrites growth and also hinder the polysulfide shuttle effect.We reveal that the 3D structural network of GFs layer with abundant polar sites helps to homogenize Li-ion flux,leading to uniform Li-ion deposition.Meanwhile,the polar moieties also immobilize the lithium polysulfides and protect the Li metal from the side-reaction.As a result,the anodeprotected batteries have shown significantly enhanced performance.A high coulombic efficiency of 96% after 160 cycles has been achieved in the Li-Cu half cells.The Li-Li symmetric cells exhibit a prolonged lifespan for 800 h with voltage hysteresis(10 mV).With the as-prepared GFs layer,the Li-S battery shows approximately 14% higher capacity retention than the pristine battery at 0.5 C after 100 cycles.Our work presents that this gelatin-based bi-functional interlayer provides a viable strategy for the manufacturing of advanced Li-S batteries.展开更多
Lithium-sulfur battery(LSB) has high energy density but is limited by the polysulfides shuttle and dendrite growth during cycling. Herein, a free-standing cellulose nanofiber(CNF) separator is designed and fabricated ...Lithium-sulfur battery(LSB) has high energy density but is limited by the polysulfides shuttle and dendrite growth during cycling. Herein, a free-standing cellulose nanofiber(CNF) separator is designed and fabricated in isopropanol/water suspension through vacuum filtration progress. CNFs with abundant polar oxygen-containing functional groups can chemically immobilize the polysulfides, and suppress the formation of the dendrites by controlling the surface morphology of the SEI on lithium metal in LSB. The isopropanol content in a suspension can fine-tune the pore structure of the membrane to achieve optimal electrochemical performance. The prepared separator displays integrated advantages of an ultrathin thickness(19 μm), lightweight(0.87 mg cm^(-2)), extremely high porosity(98.05%), and decent electrolyte affinity. As a result, the discharge capacity of the LSB with CNF separator at the first and 100 th cycle is 1.4 and 1.3 times that of PP separator, respectively. Our research provides an environmentalfriendly and facile strategy for the preparation of multifunctional separators for LSBs.展开更多
Biochar is extensively used as an effective soil amendment for environmental remediation.In addition to its strong contaminant sorption capability, biochar also plays an important role in chemical transformation of co...Biochar is extensively used as an effective soil amendment for environmental remediation.In addition to its strong contaminant sorption capability, biochar also plays an important role in chemical transformation of contaminant due to its inherent redox-active moieties.However, the transformation efficiency of inorganic contaminants is generally very limited when the direct adsorption of contaminants on biochar is inefficient. The present study demonstrates the role of Fe ion as an electron shuttle to enhance Cr(Ⅵ) reduction by biochars. Batch experiments were conducted to examine the effects of Fe(Ⅲ) levels,pyrolysis temperature of biochar, initial solution pH, and biochar dosage on the efficiency of Cr(Ⅵ) removal. Results showed a significant enhancement in Cr(Ⅵ) reduction with an increase in Fe(Ⅲ) concentration and a decrease of initial pH. Biochar produced at higher pyrolysis temperatures(e.g., 700°C) favored Cr(Ⅵ) removal, especially in the presence of Fe(Ⅲ), while a higher biochar dosage proved unfavorable likely due to the agglomeration or precipitation of biochar. Speciation analysis of Fe and Cr elements on the surface of biochar and in the solution further confirmed the role of Fe ion as an electron shuttle between biochar and Cr(Ⅵ). The present findings provide a potential strategy for the advanced treatment of Cr(Ⅵ) at low concentrations as well as an insight into the environmental fate of Cr(Ⅵ) and other micro-pollutants in soil or aqueous compartments containing Fe and natural or engineered carbonaceous materials.展开更多
The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusi...The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue.Herein,we employed in situ/operando X-ray absorption spectroscopy(XAS)to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces,respectively,in a real-time condition.After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix(BSOC),we found the Li/S cell showed greatly improved sulfur utilization and longer life span.The operando S Kedge XAS results revealed that the BSOC modification was bi-functional:trapping polysulfides and catalyzing conversion of sulfur species simultaneously.We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection.Our results could offer potential stratagem for designing more advanced Li/S cells.展开更多
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-elect...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.展开更多
Canopy air curtain （CAC） technology has been developed by the National Institute for Occupational Safety and Health （NIOSH） for use on continuous miners and subsequently roof bolting machines in underground coal m...Canopy air curtain （CAC） technology has been developed by the National Institute for Occupational Safety and Health （NIOSH） for use on continuous miners and subsequently roof bolting machines in underground coal mines to protect operators of these machines from overexposure to respirable coal mine dust. The next logical progression is to develop a CAC for shuttle cars to protect operators from the same overexposures. NIOSH awarded a contract to Marshall University and J.H. Fletcher to develop the shuttle car CAC. NIOSH conducted laboratory testing to determine the dust control efficiency of the shuttle car CAC. Testing was conducted on two different cab configurations： a center drive similar to that on a Joy 10SC32AA cab model and an end drive similar to that on a Joy 10SC32AB cab model. Three different ventilation velocities were tested-0.61, 2.0, 4.3 rrds （120, 400, and 850 fpm）. The lowest, 0.61 m/s （120 fpm）, represented the ventilation velocity encountered during loading by the continuous miner, while the 4.3 m/s （850 fpm） velocity represented ventilation velocity airflow over the shuttle car while tramming against ventilation airflow. Test results showed an average of the dust control efficiencies ranging from 74 to 83% for 0.61 m/s （120 fpm）, 39%-43% for 2.0 m/s （400 fpm）, and 6%-16% for 4.3 m/s （850 fpm）. Incorporating an airflow spoiler to the shuttle car CAC design and placing the CAC so that it is located 22.86 cm （9 in.） forward of the operator improved the dust control efficiency to 51%-55% for 4.3 m/s （850 fpm） with minimal impact on dust control efficiencies for lower ventilation velocities. These laboratory tests demonstrate that the newly developed shuttle car CAC has the potential to successfully protect shuttle car operators from coal mine respirable dust overexposures.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
Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aque...Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aqueous Li-O_(2)batteries to enhance their discharge capacity and reduce charge overpotential.However,the shuttle effect of RMs in the electrolyte solution usually leads to corrosion of the Li metal anode and uneven Li deposition on the anode surface,resulting in unwanted consumption of electrocatalysts and deterioration of the cells.It is therefore necessary to take some measures to prevent the shuttle effect of RMs and fully utilize the soluble electrocatalysts.Herein,we summarize the strategies to suppress the RM shuttle effect reported in recent years,including electrolyte additives,protective separators and electrode modification.The mechanisms of these strategies are analyzed and their corresponding requirements are discussed.The electrochemical properties of Li-O_(2)batteries with different strategies are summarized and compared.The challenges and perspectives on preventing the shuttle effect of RMs are described for future study.This review provides guidance for achieving shuttle-free redox mediation and for designing Li-O_(2)cells with a long cycle life,high energy efficiency and highly reversible electrochemical reactions.展开更多
Designing a durable lithium metal anode for solid state batteries requires a controllable and uniform deposition of lithium, and the metal lithium layer should maintain a good interface contact with solid state electr...Designing a durable lithium metal anode for solid state batteries requires a controllable and uniform deposition of lithium, and the metal lithium layer should maintain a good interface contact with solid state electrolyte during cycles. In this work, we construct a robust functional interface layer on the modified LiB electrode which considerably improves the electrochemical stability of lithium metal electrode in solid state batteries. It is found that the functional interface layer consisting of polydioxolane, polyiodide ion and Li TFSI effectively restrains the growth of lithium dendrites through the redox shuttle reaction of I-/I3-and maintains a good contact between lithium anode and solid electrolyte during cycles. Benefit from these two advantages, the modified Li-B anode exhibits a remarkable cyclic performance in comparison with those of the bare Li-B anode.展开更多
The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem（TSP）,which has been widely applied in the conventional automated storage and retri...The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem（TSP）,which has been widely applied in the conventional automated storage and retrieval system（AS/RS）.However,the previous mathematical models in conventional AS/RS do not match multi-tier shuttle warehousing systems（MSWS） because the characteristics of parallel retrieval in multiple tiers and progressive vertical movement destroy the foundation of TSP.In this study,a two-stage open queuing network model in which shuttles and a lift are regarded as servers at different stages is proposed to analyze system performance in the terms of shuttle waiting period（SWP） and lift idle period（LIP） during transaction cycle time.A mean arrival time difference matrix for pairwise stock keeping units（SKUs） is presented to determine the mean waiting time and queue length to optimize the storage assignment problem on the basis of SKU correlation.The decomposition method is applied to analyze the interactions among outbound task time,SWP,and LIP.The ant colony clustering algorithm is designed to determine storage partitions using clustering items.In addition,goods are assigned for storage according to the rearranging permutation and the combination of storage partitions in a 2D plane.This combination is derived based on the analysis results of the queuing network model and on three basic principles.The storage assignment method and its entire optimization algorithm method as applied in a MSWS are verified through a practical engineering project conducted in the tobacco industry.The applying results show that the total SWP and LIP can be reduced effectively to improve the utilization rates of all devices and to increase the throughput of the distribution center.展开更多
By employing the pUC19 as a backbone,the regulatory and signal sequences which encode kanamycin resistance, and mycobacterial plasmid origin of replication (oriM) were cloned into the pUC19. The recombinant E. Coli-my...By employing the pUC19 as a backbone,the regulatory and signal sequences which encode kanamycin resistance, and mycobacterial plasmid origin of replication (oriM) were cloned into the pUC19. The recombinant E. Coli-mycobacteria shuttle expression plasmid PBCG-8000 was constructed. The PBCG-8000 was able to replicate in both E. Coli and mycobacteria (including BCG) systems, and to confer stable kanamycin resistance upon transformants. The study should facilitate the development of BCG and other mycobacteria into multivalent vaccine vectors.展开更多
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.Howeve...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 sin-gle 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-N_(4))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.展开更多
According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-b...According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-biodegradable,thus they produce a mass of waste disposal and cause environmental pollution is-sue.For the purpose of transforming waste into wealth and reducing environmental pollution,nitrogen and sulfur co-doped carbon nanofiber/carbon black(N,S-CNF/CB)composite derived from the discarded cigarette filters is employed to modify glass fiber(GF)separator for the first time in this study.N,S-CNF improves binding ability towards sodium polysulfides(SPSs)by chemisorption.Non-polar CB limits the dissolution of SPSs in the liquid electrolyte by physisorption.The experiment and density functional theory calculation results indicate that a RT-Na/S battery with a N,S-CNF/CB+GF separator exhibits good cycling stability and rate performance.After 100 cycles at a low current rate of 0.1 C,a RT-Na/S battery with a sulfur mass fraction of 71%delivers a discharge capacity of 703 mAh g^(−1).In addition,at a high current rate of 0.5 C,a discharge capacity of 527 mAh g^(−1) is still maintained after 900 cycles with a very low capacity fading rate of 0.035%per cycle.展开更多
Polysulfide absorption in a micropore-rich structure has been reported to be capable of efficiently confining the shuttle effect for high-performance lithium-sulfur(Li–S)batteries.Here,a labyrinth maze-like spherical...Polysulfide absorption in a micropore-rich structure has been reported to be capable of efficiently confining the shuttle effect for high-performance lithium-sulfur(Li–S)batteries.Here,a labyrinth maze-like spherical honeycomb-like carbon with micropore-rich structure was synthesized,which is employed as a template host material of sulfur to study the shuttle effects.The results strongly confirm that a diffusion controlled process rather than an absorption resulted surface-controlled process occurs in an even micropore-rich cathode but still greatly inhibits the shuttle effect.Thus,the battery achieves a high initial discharge specific capacity of 1120 mAh g1 at 0.25 C and super cycling stability for 1635 cycles with only 0.035%capacity decay per cycle with 100%Coulombic efficiency.We would like to propose a new mechanism for shuttle effect inhibition in micropores.In terms of the diffusion control process in microporous paths of a labyrinth maze structure,polysulfides experience a long travel to realize continuous reductions of sulfur and polysulfides until formation of the final solid product.This efficiently prevents the polysulfides escaping to electrolyte.The labyrinth maze-like honeycomb structure also offers fast electron transfer and enhanced mass transport as well as robust mechanical strength retaining intact structure for long cycle life.This work sheds lights on new fundamental insights behind the shuttle effects with universal significance while demonstrating prominent merits of a robust labyrinth maze-like structure in high performance cathode for high-performance Li–S batteries.展开更多
基金the financial support from the Natural Science Foundation of Jiangsu Province(BK20231292)the Jiangsu Agricultural Science and Technology Innovation Fund(CX(24)3091)+6 种基金the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX25_1429)the National Key R&D Program of China(2024YFE0109200)the Fundamental Research Funds for the Central Universities(No.2024300440)Guangdong Basic and Applied Basic Research Foundation(2025A1515011098)the National Natural Science Foundation of China(12464032)the Natural Science Foundation of Jiangxi Province(20232BAB201032)Ji'an Science and Technology Plan Project(2024H-100301)。
文摘Zn-I_(2) batteries have emerged as promising next-generation energy storage systems owing to their inherent safety,environmental compatibility,rapid reaction kinetics,and small voltage hysteresis.Nevertheless,two critical challenges,i.e.,zinc dendrite growth and polyiodide shuttle effect,severely impede their commercial viability.To conquer these limitations,this study develops a multifunctional separator fabricated from straw-derived carboxylated nanocellulose,with its negative charge density further reinforced by anionic polyacrylamide incorporation.This modification simultaneously improves the separator’s mechanical properties,ionic conductivity,and Zn^(2+)ion transfer number.Remarkably,despite its ultrathin 20μm profile,the engineered separator demonstrates exceptional dendrite suppression and parasitic reaction inhibition,enabling Zn//Zn symmetric cells to achieve impressive cycle life(>1800 h at 2 m A cm^(-2)/2 m Ah cm^(-2))while maintaining robust performance even at ultrahigh areal capacities(25 m Ah cm^(-2)).Additionally,the separator’s anionic characteristic effectively blocks polyiodide migration through electrostatic repulsion,yielding Zn-I_(2) batteries with outstanding rate capability(120.7 m Ah g^(-1)at 5 A g^(-1))and excellent cyclability(94.2%capacity retention after 10,000 cycles).And superior cycling stability can still be achieved under zinc-deficient condition and pouch cell configuration.This work establishes a new paradigm for designing high-performance zinc-based energy storage systems through rational separator engineering.
文摘A functional interlayer based on two-dimensional(2D)porous modified vermiculite nanosheets(PVS)was obtained by acid-etching vermiculite nanosheets.The as-obtained 2D porous nanosheets exhibited a high specific surface area of 427 m^(2)·g^(-1)and rich surface active sites,which help restrain polysulfides(LiPSs)through good physi-cal and chemical adsorption,while simultaneously accelerating the nucleation and dissolution kinetics of Li_(2)S,effec-tively suppressing the shuttle effect.The assembled lithium-sulfur batteries(LSBs)employing the PVS-based inter-layer delivered a high initial discharge capacity of 1386 mAh·g^(-1)at 0.1C(167.5 mAh·g^(-1)),long-term cycling stabil-ity,and good rate property.
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.
文摘Nowadays, the Multi-Shuttle and Multi-Station Transportation System (MMTS)<span><span><span style="font-family:;" "=""> is one of the most interesting research topics in many fields of industries. It is an effective solution to reduce unexpected accidents that occur during transportation as well as increase productivity in manufacturing. The aim of this paper is to introduce the controller design for the MMTS which is built in our BK-Recme BioMech Lab at Ho Chi Minh City University of Technology (VNU-HCM), Viet Nam. Based on the design of this system, the control algorithms will be conducted to check the operation of the whole system. To evaluate the feasibility and effectiveness of this model, we design a series of random instances for different quantities of nodes as well as the different quantities of shuttles. Our system includes 4 stations and 6 shuttles which are assembled in the serial chain system. However, the number of stations and number of shuttles can be expanded to any desired ones which are based on the requirement of the industries. In this paper, we mainly focus on the controller design of this system to make it operate in an effective way that the goods will be transported and delivered to the target station as fast as possible. In order to solve the large</span></span></span><span><span><span style="font-family:;" "="">-</span></span></span><span><span><span style="font-family:;" "="">scale instances and realistic transport prob<span>lems, we propose three algorithms for three progresses as shuttles calling</span>, path reading and shuttles communicating. The shuttles calling is to decide which <span>shuttle should be called to the star</span></span></span></span><span><span><span style="font-family:;" "="">t</span></span></span><span><span><span style="font-family:;" "="">-node. Path reading to determine the shortest</span></span></span><span><span><span style="font-family:;" "=""> <span>way to go from start-node to end-node. Finally, shuttles communicating,</span> which allow one shuttle to interact with the next shuttles so we have a loop of orders (shuttle 1 to shuttle 2;shuttle 2 to shuttle 3;etc</span></span></span><span><span><span style="font-family:;" "="">.</span></span></span><span><span><span style="font-family:;" "="">;shuttle n-1 to shuttle n). This proposes solution can help us to solve the huge numbers of shuttles <span>and stations in the system. The specific result of this study is applying</span> Dijkstra’s algorithm to propose an algorithm that allows handling a transportation system without caring about the number of shuttles as well as the number of stations for the closed-loop path. Several test problems are carried out in order to check the feasibility and the effectiveness of our purposed control algorithm.</span></span></span>
基金This work was supported by the National Natu- ral Science Foundation of China （No.21072152 and No.21101115）.
文摘Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells （DSSCs）. The DSSCs incorporating tris（1,10-phenanthroline）eobalt（Ⅱ/Ⅲ）-based redox elec- trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the w-conjugated spacers of organic dyes upon the photovoltage and photocur- rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination.
基金supported by the National Natural Science Foundation of China (No. 51861165101)。
文摘Lithium-sulfur(Li-S) battery is one of the best candidates for the next-generation energy storage system due to its high theoretical capacity(1675 mA h-1),low cost and environment friendliness.However,lithium(Li) dendrites formation and polysulfide shuttle effect are two major challenges that limit the commercialization of Li-S batteries.Here we design a facile bifunctional interlayer of gelatin-based fibers(GFs),aiming to protect the Li anode surface from the dendrites growth and also hinder the polysulfide shuttle effect.We reveal that the 3D structural network of GFs layer with abundant polar sites helps to homogenize Li-ion flux,leading to uniform Li-ion deposition.Meanwhile,the polar moieties also immobilize the lithium polysulfides and protect the Li metal from the side-reaction.As a result,the anodeprotected batteries have shown significantly enhanced performance.A high coulombic efficiency of 96% after 160 cycles has been achieved in the Li-Cu half cells.The Li-Li symmetric cells exhibit a prolonged lifespan for 800 h with voltage hysteresis(10 mV).With the as-prepared GFs layer,the Li-S battery shows approximately 14% higher capacity retention than the pristine battery at 0.5 C after 100 cycles.Our work presents that this gelatin-based bi-functional interlayer provides a viable strategy for the manufacturing of advanced Li-S batteries.
基金supported by the National Key Research and Development Program(2018YFB1501500)the National Science Foundation for Excellent Young Scholars of China(21922815)+2 种基金the National Key Research and Development(R&D)Program of China(2020YFB1505800)the Research and Development Project of Key Core and Common Technology of Shanxi Province(2020XXX014)the Fundamental Research Program of Shanxi Province(20210302123008,20210302124101)。
文摘Lithium-sulfur battery(LSB) has high energy density but is limited by the polysulfides shuttle and dendrite growth during cycling. Herein, a free-standing cellulose nanofiber(CNF) separator is designed and fabricated in isopropanol/water suspension through vacuum filtration progress. CNFs with abundant polar oxygen-containing functional groups can chemically immobilize the polysulfides, and suppress the formation of the dendrites by controlling the surface morphology of the SEI on lithium metal in LSB. The isopropanol content in a suspension can fine-tune the pore structure of the membrane to achieve optimal electrochemical performance. The prepared separator displays integrated advantages of an ultrathin thickness(19 μm), lightweight(0.87 mg cm^(-2)), extremely high porosity(98.05%), and decent electrolyte affinity. As a result, the discharge capacity of the LSB with CNF separator at the first and 100 th cycle is 1.4 and 1.3 times that of PP separator, respectively. Our research provides an environmentalfriendly and facile strategy for the preparation of multifunctional separators for LSBs.
基金supported by the National Key Research and Development Program of China (No. 2016YFA0203102)the National Basic Research Program of China (No. 2015CB932003)+1 种基金the National Natural Science Foundation of China (Nos. 21777173, 21522705)the support from the Youth Innovation Promotion Association CAS
文摘Biochar is extensively used as an effective soil amendment for environmental remediation.In addition to its strong contaminant sorption capability, biochar also plays an important role in chemical transformation of contaminant due to its inherent redox-active moieties.However, the transformation efficiency of inorganic contaminants is generally very limited when the direct adsorption of contaminants on biochar is inefficient. The present study demonstrates the role of Fe ion as an electron shuttle to enhance Cr(Ⅵ) reduction by biochars. Batch experiments were conducted to examine the effects of Fe(Ⅲ) levels,pyrolysis temperature of biochar, initial solution pH, and biochar dosage on the efficiency of Cr(Ⅵ) removal. Results showed a significant enhancement in Cr(Ⅵ) reduction with an increase in Fe(Ⅲ) concentration and a decrease of initial pH. Biochar produced at higher pyrolysis temperatures(e.g., 700°C) favored Cr(Ⅵ) removal, especially in the presence of Fe(Ⅲ), while a higher biochar dosage proved unfavorable likely due to the agglomeration or precipitation of biochar. Speciation analysis of Fe and Cr elements on the surface of biochar and in the solution further confirmed the role of Fe ion as an electron shuttle between biochar and Cr(Ⅵ). The present findings provide a potential strategy for the advanced treatment of Cr(Ⅵ) at low concentrations as well as an insight into the environmental fate of Cr(Ⅵ) and other micro-pollutants in soil or aqueous compartments containing Fe and natural or engineered carbonaceous materials.
基金financially supported by the National Key R&D Program of China(2016YFB0100100)the National Natural Science Foundation of China(Nos.21433013,U1832218)the support from China Scholarship Council
文摘The polysulfides shuttle effect represents a great challenge in achieving high capacity and long lifespan of lithium/sulfur(Li/S)cells.A comprehensive understanding of the shuttle-related sulfur speciation and diffusion process is vital for addressing this issue.Herein,we employed in situ/operando X-ray absorption spectroscopy(XAS)to trace the migration of polysulfides across the Li/S cells by precisely monitoring the sulfur chemical speciation at the cathodic electrolyte-separator and electrolyte-anode interfaces,respectively,in a real-time condition.After we adopted a shuttle-suppressing strategy by introducing an electrocatalytic layer of twinborn bismuth sulfide/bismuth oxide nanoclusters in a carbon matrix(BSOC),we found the Li/S cell showed greatly improved sulfur utilization and longer life span.The operando S Kedge XAS results revealed that the BSOC modification was bi-functional:trapping polysulfides and catalyzing conversion of sulfur species simultaneously.We elucidated that the polysulfide trapping-and-catalyzing effect of the BSOC electrocatalytic layer resulted in an effective lithium anode protection.Our results could offer potential stratagem for designing more advanced Li/S cells.
基金support from the “Joint International Laboratory on Environmental and Energy Frontier Materials”“Innovation Research Team of High-Level Local Universities in Shanghai”support from the National Natural Science Foundation of China (22209103)
文摘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.
文摘Canopy air curtain （CAC） technology has been developed by the National Institute for Occupational Safety and Health （NIOSH） for use on continuous miners and subsequently roof bolting machines in underground coal mines to protect operators of these machines from overexposure to respirable coal mine dust. The next logical progression is to develop a CAC for shuttle cars to protect operators from the same overexposures. NIOSH awarded a contract to Marshall University and J.H. Fletcher to develop the shuttle car CAC. NIOSH conducted laboratory testing to determine the dust control efficiency of the shuttle car CAC. Testing was conducted on two different cab configurations： a center drive similar to that on a Joy 10SC32AA cab model and an end drive similar to that on a Joy 10SC32AB cab model. Three different ventilation velocities were tested-0.61, 2.0, 4.3 rrds （120, 400, and 850 fpm）. The lowest, 0.61 m/s （120 fpm）, represented the ventilation velocity encountered during loading by the continuous miner, while the 4.3 m/s （850 fpm） velocity represented ventilation velocity airflow over the shuttle car while tramming against ventilation airflow. Test results showed an average of the dust control efficiencies ranging from 74 to 83% for 0.61 m/s （120 fpm）, 39%-43% for 2.0 m/s （400 fpm）, and 6%-16% for 4.3 m/s （850 fpm）. Incorporating an airflow spoiler to the shuttle car CAC design and placing the CAC so that it is located 22.86 cm （9 in.） forward of the operator improved the dust control efficiency to 51%-55% for 4.3 m/s （850 fpm） with minimal impact on dust control efficiencies for lower ventilation velocities. These laboratory tests demonstrate that the newly developed shuttle car CAC has the potential to successfully protect shuttle car operators from coal mine respirable dust overexposures.
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financially supported by the Tsinghua-Foshan Innovation Special Fund(Grant No.2018THFS0409)the China Postdoctoral Science Foundation(Grant No.2019M650668)the National Key Research and Development Program of China(Grant No.2016YFA0201003)。
文摘Rechargeable lithium-oxygen(Li-O_(2))batteries are the next generation energy storage devices due to their ultrahigh theoretical capacity.Redox mediators(RMs)are widely used as a homogenous electrocatalyst in non-aqueous Li-O_(2)batteries to enhance their discharge capacity and reduce charge overpotential.However,the shuttle effect of RMs in the electrolyte solution usually leads to corrosion of the Li metal anode and uneven Li deposition on the anode surface,resulting in unwanted consumption of electrocatalysts and deterioration of the cells.It is therefore necessary to take some measures to prevent the shuttle effect of RMs and fully utilize the soluble electrocatalysts.Herein,we summarize the strategies to suppress the RM shuttle effect reported in recent years,including electrolyte additives,protective separators and electrode modification.The mechanisms of these strategies are analyzed and their corresponding requirements are discussed.The electrochemical properties of Li-O_(2)batteries with different strategies are summarized and compared.The challenges and perspectives on preventing the shuttle effect of RMs are described for future study.This review provides guidance for achieving shuttle-free redox mediation and for designing Li-O_(2)cells with a long cycle life,high energy efficiency and highly reversible electrochemical reactions.
基金supported by the National Natural Science Foundation of China (NO. 21805113)the Fundamental Research Funds for the Central Universities (NO. 11618410 and NO. 11619103)the China Postdoctoral Science Foundation (NO. 2019M653271)。
文摘Designing a durable lithium metal anode for solid state batteries requires a controllable and uniform deposition of lithium, and the metal lithium layer should maintain a good interface contact with solid state electrolyte during cycles. In this work, we construct a robust functional interface layer on the modified LiB electrode which considerably improves the electrochemical stability of lithium metal electrode in solid state batteries. It is found that the functional interface layer consisting of polydioxolane, polyiodide ion and Li TFSI effectively restrains the growth of lithium dendrites through the redox shuttle reaction of I-/I3-and maintains a good contact between lithium anode and solid electrolyte during cycles. Benefit from these two advantages, the modified Li-B anode exhibits a remarkable cyclic performance in comparison with those of the bare Li-B anode.
基金Supported by National Natural Science Foundation of China(Grant No.661403234)Shandong Provincial Science and Techhnology Development Plan of China(Grant No.2014GGX106009)
文摘The current mathematical models for the storage assignment problem are generally established based on the traveling salesman problem（TSP）,which has been widely applied in the conventional automated storage and retrieval system（AS/RS）.However,the previous mathematical models in conventional AS/RS do not match multi-tier shuttle warehousing systems（MSWS） because the characteristics of parallel retrieval in multiple tiers and progressive vertical movement destroy the foundation of TSP.In this study,a two-stage open queuing network model in which shuttles and a lift are regarded as servers at different stages is proposed to analyze system performance in the terms of shuttle waiting period（SWP） and lift idle period（LIP） during transaction cycle time.A mean arrival time difference matrix for pairwise stock keeping units（SKUs） is presented to determine the mean waiting time and queue length to optimize the storage assignment problem on the basis of SKU correlation.The decomposition method is applied to analyze the interactions among outbound task time,SWP,and LIP.The ant colony clustering algorithm is designed to determine storage partitions using clustering items.In addition,goods are assigned for storage according to the rearranging permutation and the combination of storage partitions in a 2D plane.This combination is derived based on the analysis results of the queuing network model and on three basic principles.The storage assignment method and its entire optimization algorithm method as applied in a MSWS are verified through a practical engineering project conducted in the tobacco industry.The applying results show that the total SWP and LIP can be reduced effectively to improve the utilization rates of all devices and to increase the throughput of the distribution center.
文摘By employing the pUC19 as a backbone,the regulatory and signal sequences which encode kanamycin resistance, and mycobacterial plasmid origin of replication (oriM) were cloned into the pUC19. The recombinant E. Coli-mycobacteria shuttle expression plasmid PBCG-8000 was constructed. The PBCG-8000 was able to replicate in both E. Coli and mycobacteria (including BCG) systems, and to confer stable kanamycin resistance upon transformants. The study should facilitate the development of BCG and other mycobacteria into multivalent vaccine vectors.
基金financially supported by the National Natural Science Foundation of China (No.51874197)Natural Science Foundation of Shanghai (Nos.21ZR1429400,22ZR1429700)
文摘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 sin-gle 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-N_(4))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.
基金supported by the National Natural Science Foundation of China(Nos.51631004 and 52130101)the Basic Construction Fund in Jilin Province Budget for 2019(No.2019C042-8).
文摘According to a statistic,approximately 6 trillion cigarettes are smoked each year all over the world,which produces approximately 1.2 million tons of discarded cigarette butts.The discarded cigarette filters are non-biodegradable,thus they produce a mass of waste disposal and cause environmental pollution is-sue.For the purpose of transforming waste into wealth and reducing environmental pollution,nitrogen and sulfur co-doped carbon nanofiber/carbon black(N,S-CNF/CB)composite derived from the discarded cigarette filters is employed to modify glass fiber(GF)separator for the first time in this study.N,S-CNF improves binding ability towards sodium polysulfides(SPSs)by chemisorption.Non-polar CB limits the dissolution of SPSs in the liquid electrolyte by physisorption.The experiment and density functional theory calculation results indicate that a RT-Na/S battery with a N,S-CNF/CB+GF separator exhibits good cycling stability and rate performance.After 100 cycles at a low current rate of 0.1 C,a RT-Na/S battery with a sulfur mass fraction of 71%delivers a discharge capacity of 703 mAh g^(−1).In addition,at a high current rate of 0.5 C,a discharge capacity of 527 mAh g^(−1) is still maintained after 900 cycles with a very low capacity fading rate of 0.035%per cycle.
基金Supplementary data to this article can be found online at https://doi.org/10.1016/j.matre.2022.100159.
文摘Polysulfide absorption in a micropore-rich structure has been reported to be capable of efficiently confining the shuttle effect for high-performance lithium-sulfur(Li–S)batteries.Here,a labyrinth maze-like spherical honeycomb-like carbon with micropore-rich structure was synthesized,which is employed as a template host material of sulfur to study the shuttle effects.The results strongly confirm that a diffusion controlled process rather than an absorption resulted surface-controlled process occurs in an even micropore-rich cathode but still greatly inhibits the shuttle effect.Thus,the battery achieves a high initial discharge specific capacity of 1120 mAh g1 at 0.25 C and super cycling stability for 1635 cycles with only 0.035%capacity decay per cycle with 100%Coulombic efficiency.We would like to propose a new mechanism for shuttle effect inhibition in micropores.In terms of the diffusion control process in microporous paths of a labyrinth maze structure,polysulfides experience a long travel to realize continuous reductions of sulfur and polysulfides until formation of the final solid product.This efficiently prevents the polysulfides escaping to electrolyte.The labyrinth maze-like honeycomb structure also offers fast electron transfer and enhanced mass transport as well as robust mechanical strength retaining intact structure for long cycle life.This work sheds lights on new fundamental insights behind the shuttle effects with universal significance while demonstrating prominent merits of a robust labyrinth maze-like structure in high performance cathode for high-performance Li–S batteries.
