Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temp...Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.展开更多
This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0...This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.1)Mo_(0.05)O_(3-δ)(B S CNM_(0.05)),Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.05)Mo_(0.1)O_(3-δ)(BSCNM_(0.1)),and Ba_(0.6)Sr_(0.4)Co_(0.85)Mo_(0.15)O_(3-δ)(BSCM)—with Mo doping contents of 5mol%,10mol%,and15mol%,respectively,were successfully prepared using the sol-gel method.The effects of Mo doping on the crystal structure,conductivity,thermal expansion coefficient,oxygen reduction reaction(ORR)activity,and electrochemical performance were systematically evaluated using X-ray diffraction analysis,thermally induced characterization,electrochemical impedance spectroscopy,and single-cell performance tests.The results revealed that Mo doping could improve the conductivity of the materials,suppress their thermal expansion effects,and significantly improve the electrochemical performance.Surface chemical state analysis using X-ray photoelectron spectroscopy revealed that 5mol%Mo doping could facilitate a high adsorbed oxygen concentration leading to enhanced ORR activity in the materials.Density functional theory calculations confirmed that Mo doping promoted the ORR activity in the materials.At an operating temperature of 600℃,the BSCNM_(0.05)cathode material exhibited significantly enhanced electrochemical impedance characteristics,with a reduced area specific resistance of 0.048Ω·cm~2,which was lower than that of the undoped BSCN matrix material by 32.39%.At the same operating temperature,an anode-supported single cell using a BSCNM_(0.05)cathode achieved a peak power density of 1477 mW·cm^(-2),which was 30.71%,56.30%,and 171.50%higher than those of BSCN,BSCNM_(0.1),and B SCM,respectively.The improved ORR activity and electrochemical performance of BSCNM_(0.05)indicate that it can be used as a cathode material in low-temperature solid oxide fuel cells.展开更多
This article investigates the low-temperature formation of aluminide coatings on a Ni-base superalloy by pack cementation process. The pack cemented coatings characteristic of high density and homogeneity possess a tw...This article investigates the low-temperature formation of aluminide coatings on a Ni-base superalloy by pack cementation process. The pack cemented coatings characteristic of high density and homogeneity possess a two-layer structure. The top layer mainly consists of Al3Ni2 and Al3Ni,while the bottom layer of Al3Ni2. Great efforts are made to elucidate the effects of different experimental parameters on the microstructure and the constituent distribution of the coatings. The results show that all the parameters exclusive of the pack activator （NH4Cl） content produce effect on the coating thickness,but do not on the microstructure and the constituent distribution. The pack activator （NH4Cl） content affects neither the coating thickness nor structure and constituent distribution. The parabolic relationship between the coating thickness and the deposition time suggests that the process is diffusion-controlled. Furthermore,the article demonstrates a linear relationship between the coating thickness and the re-ciprocal deposition temperature.展开更多
A series of low-temperature phase transitions of sodium aluminate solutions were studied by differential scanning calorimetry (DSC) and Raman spectroscopy. The results indicate that NaOH concentration is a primary imp...A series of low-temperature phase transitions of sodium aluminate solutions were studied by differential scanning calorimetry (DSC) and Raman spectroscopy. The results indicate that NaOH concentration is a primary impact factor for the binary eutectic point and ice melting temperature of sodium aluminate solutions with low NaOH concentration. In addition, the phase transition process of sodium aluminate solutions with low NaOH concentration from 123.15 to 283.15 K is divided into four steps: non-crystal to crystal, ternary eutectic reaction, binary eutectic reaction and ice melt. The projection phase diagram of NaOH-Al(OH)3-H2O system at low temperature was plotted, in which the ternary eutectic temperature for sodium aluminate solutions is 183.15 K.展开更多
The inherent advantages of ionic liquids （ILs） in electrochemistry have received extensive attention in recent two decades. As a new generation of ILs, non-haloaluminate ILs exhibit better benefits and fewer drawbac...The inherent advantages of ionic liquids （ILs） in electrochemistry have received extensive attention in recent two decades. As a new generation of ILs, non-haloaluminate ILs exhibit better benefits and fewer drawbacks compared to haloaluminate based ILs, which are more qualified for metal electrodeposition, especially reactive metals. In this brief review, the recent developments regard- ing the application of non-haloaluminate ILs as solvents for low-temperature electrodeposition of rare-earth （RE） metals are outlined. In addition, the current problems and an outlook on future research are presented.展开更多
Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-form...Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-forming properties and high dielectric constant.However,the elevated freezing point,high viscosity,and strong solvation energy of EC significantly hinder the transport rate of Li^(+)and the desolvation process at low temperatures.This leads to substantial capacity loss and even lithium plating on graphite anodes.Herein,we have developed an efficient electrolyte system specifically designed for lowtemperature conditions,which consists of 1.0 M lithium bis(fluorosulfonyl)imide(LiFSI)in isoxazole(IZ)with fluorobenzene(FB)as an uncoordinated solvent and fluoroethylene carbonate(FEC)as a filmforming co-solvent.This system effectively lowers the desolvation energy of Li^(+)through dipole-dipole interactions.The weak solvation capability allows more anions to enter the solvation sheath,promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs)that enhance the transport rate of Li^(+)while maintaining high ionic conductivity across a broad temperature range.Moreover,the formation of inorganic-dominant interfacial phases on the graphite anode,induced by fluoroethylene carbonate,significantly enhances the kinetics of Li^(+)transport.At a low temperature of-20℃,this electrolyte system achieves an impressive reversible capacity of 200.9 mAh g^(-1)in graphite half-cell,which is nearly three times that observed with conventional EC-based electrolytes,demonstrating excellent stability throughout its operation.展开更多
To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the character...To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the characteristics of low-tempe rature sulfuric acid deco mposition.When a single monazite was leached using 75 wt% H_(2)SO_(4) solution with phosphoric acid,the size and number of monazite particles in the washing slag gradually decrease with the increase in phosphoric acid content in the leaching solution.The monazite phase can hardly be found in the slag when the phosphoric acid content reaches 70 g/L,which indicates that phosphoric acid is favorable for monazite decomposition.The mixed rare earth concentrate was leached by 75 wt% H_(2)SO_(4) containing 70 g/L phosphoric acid,the mineral compositions of the washing slag are only gypsum and unwashed rare earth sulfuric acid.After cyclic leaching of75 wt% H_(2)SO_(4),the mineral compositions of the primary leaching washing slag are mainly undecomposed monazite,rare earth sulfate and calcium sulfate.However,monazite is not found in the mineral phase of the second and third leaching washing slag.The leaching rates of rare earth and phosphorus gradually increase with the increase in cyclic leaching times.In addition,the phosphoric acid content in the leaching solution increases with the increase in the number of cyclic leaching time.However,the rising trend decreases when the phosphoric acid content reaches 50 g/L by adsorption and crystallization of phosphoric acid.A small amount of water can be used to clean the leaching residue before washing to recover the more soluble phosphorus acid according to the difference of dissolution between phosphoric acid and rare earth sulfuric acid.展开更多
Because of their excellent low-temperature(−15 to−40℃)tolerance,sodium-ion batteries are emerging as a complement to lithium-ion batteries for use in extremely cold environments(e.g.high-latitude areas).Hard carbon h...Because of their excellent low-temperature(−15 to−40℃)tolerance,sodium-ion batteries are emerging as a complement to lithium-ion batteries for use in extremely cold environments(e.g.high-latitude areas).Hard carbon has a high low-voltage sodium storage capacity and a good initial efficiency,making it one of the most promising anode materials for sodium-ion batteries.It has a complex structure,featuring closed pores,nano graphitic domains,and surface functional groups.The sodium storage sites in hard carbon are reviewed as are the widely accepted sodium storage mechanisms.The main factors contributing to the degradation of the good low-temperature performance in hard carbon anodes are considered,including sodium dendrite formation,low ion diffusion rates,and surface-side reactions.Finally,strategies to increase the low-temperature sodium storage performance of hard carbon anodes are summarized,including bulk structure design,and improvements in interfaces and cut-off voltage.Guidance is provided for improving the low-temperature performance of hard carbon anodes to accelerate the development of these batteries.展开更多
Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aq...Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.展开更多
Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is g...Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is generally slow at low temperature,resulting in large overpotential and low current efficiency.Thus,the application of external physical fields has emerged as an effective strategy for improving the mass and charge transfer processes during electrochemical reactions.This review highlights the challenges associated with low-temperature electrochemical processes and briefly discusses recent achievements in optimizing electrodeposition processes through the use of external physical fields.The regulating effects on the optimization of the electrodeposition process and the strategies for select-ing various external physical fields,including magnetic,supergravity,and ultrasonic fields are summarized from the perspectives of equipment and mechanisms.Finally,advanced methods for in-situ characterization of external physical field-assisted electrodeposition processes are reviewed to gain a deeper understanding of metallic electrodeposition.An in-depth exploration of the mechanism by which external physical fields affect the electrode process is essential for enhancing the efficiency of metal extraction at low temperatures.展开更多
Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly im...Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly impairs seedling emergence.In this study,genetic diversity across six germination-associated phenotypic traits(RGR,RSL,RTL,RRSA,RRV,and RSVI)of 304 inbred lines was analyzed,to evaluate the capacity of these lines for low-temperature tolerance.Genome-wide association study(GWAS)was carried out by combining six germination-associated phenotypic traits and genotypic data from 30-fold resequencing.The gene ZmBARK1 was identified through integrated GWAS and RNA-seq analyses,and its association with low-temperature tolerance during maize germination was validated by quantitative real-time PCR(qRT-PCR).ZmBARK1,encoding BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1,was located on the bin 4.09 region of maize chromosome 4.Amino acid comparison and subcellular localization analyses revealed that ZmBARK1 is highly homologous to AtBAK1 and is localized to the plasma membrane of the cell,which may be involved in regulating brassinosteroid(BR)signaling.In addition,we revealed the role of ZmBARK1 in low-temperature tolerance during maize germination.Compared with wild-type(WT),the ethyl methanesulfonate(EMS)mutant zmbark1 was characterized by substantially enhanced low-temperature tolerance.Overall,these findings provide promising candidate genes,improve low-temperature tolerance in maize,and advance the understanding of regulatory mechanisms underlying maize's response to low-temperature stress.展开更多
Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This stu...Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This study explores novel coupled pretreatments of free-end largeangle pre-torsion and low-temperature aging to improve the fatigue resistance of rolled ZK60 magnesium alloy.STA(pre-torsion followed by low-temperature aging)and SAT(low-temperature aging followed by pre-torsion)samples were prepared to investigate the influences of pretreatment coupling sequences.The results of microstructure characterization reveal that pre-torsion significantly enhances the formation of tensile twins and introduces a gradient microstructure with increased dislocation density from the center to the edges.STA process resulted in the highest twinning area fraction of 35.2% and a kernel average misorientation of 0.94 at the edge.Mechanical testing demonstrated that the coupled pre-treatment obtained a better combination of strength and plasticity,significantly improved the yield strength in the compression stage,and increased the tensile-compressive yield ratio to>0.9.In the low-cycle fatigue test,the STA samples exhibited lower cyclic mean stress,a smaller cyclic hardening trend,and better hysteretic symmetry,leading to an improvement in fatigue life of up to 256%.The findings suggest that the combined pre-torsion and low-temperature aging treatments offer a promising approach to enhance the mechanical properties and fatigue resistance of ZK60 magnesium alloy,making it suitable for structural applications in demanding environments.展开更多
Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wil...Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wild-type RR,mutant sitiens(sit),and ABA-pretreated sit tomato seedlings following exposure to low-temperature(LT)stress.We found that the net photosynthetic rate,intercellular carbon dioxide concentration,transpiration rate,and stomatal conductance of sit seedlings were lower than those of RR seedlings under LT stress.The chloroplast width,area,and number of osmiophilic granules were significantly larger in sit seedlings than in RR seedlings,while the chloroplast length/width ratio was significantly lower in sit seedlings than in RR seedlings.The photochemical activity of sit seedlings was lower,and the expression of photosynthesis-related genes in sit seedlings was altered following exposure to LT stress.ABA pretreatment significantly alleviated the above phenomenon.We also conducted an RNA sequencing analysis and characterized the expression patterns of genes in tomato seedlings following exposure to LT stress.We constructed 15 cDNA libraries and identified several differentially expressed genes involved in photosynthesis,plant hormone signaling transduction,and primary and secondary metabolism.Additional analyses of genes encoding transcription factors and proteins involved in photosynthesis-related processes showed pronounced changes in expression under LT stress.Luciferase reporter assay and electrophoretic mobility shift assay revealed that WRKY22 regulates the expression of PsbA.The PSII of WRKY22 and PsbA-silenced plants was inhibited.Our findings indicate that ABA plays a role in regulating the process of photosynthesis and protecting PSII in tomato under LT stress through the WRKY22-PsbA complex.展开更多
The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for i...The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.展开更多
The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by gra...The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by grain size refinement or/and doping small amounts of alumina.Fine-grained dense 3mol%yttria-doped tetragonal zirconia polycrystal(3Y-TZP)ceramics were prepared by pressureless sintering a zirconia powder doped with 0.25wt%alumina.The LTD behaviors of as-prepared 3Y-TZP ceramics were evaluated by accelerated aging at 134℃in water.The samples sintered at 1300℃for 2 h achieve the relative density higher than 99.9%with the average grain size of 147 nm.The 3Y-TZP ceramic exhibits excellent LTD resistance that no t→m transformation takes place after 125 h accelerated aging.Large amounts of defects were observed inside grains evidenced by the high-resolution transmission electron microscopic(HRTEM)analysis.It is proposed that the presence of defects enhances the sintering kinetics and favors the present low-temperature densification.Possible reasons for defects formation were discussed and the mechanical properties of the 3Y-TZP ceramic were reported as well.展开更多
Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high s...Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high sulfur loading and lean electrolyte.The distinct behaviors of sulfur cathode in lowtemperature Li-S batteries call for special regulations of the sulfur host to improve the electrochemical performances.Here,a three-dimensional Ti_(3)C_(2)micro-cage(TCC)with an interfacial structure modulated by rich curvatures has been fabricated to propel the sulfur electrochemistry at subzero temperatures.Spectroscopic/microscopic analyses and theoretical calculations elucidate that the precipitation of ultrafine Ti-metal particles on the in-situ generated Ti_(3)C_(2)nanoribbons could trigger the self-scrolling of Ti_(3)C_(2)nanoribbons into TCC.Moreover,in-situ ultraviolet-visible spectra collected at low temperature and theoretical calculations verified that the TCC regulated by rich curvatures have effectively alleviated the Li+dissociation barrier,reduced the energy barrier for charge transfer at the electrode-electrolyte interface,and restrained the clustering and shuttling of LiPSs,thus accelerating the electrochemical conversion kinetics of sulfur species at low temperatures.The performances of the carbon-free TCC-S cathode at low temperatures have been also compared from the aspects of cathode configuration and measurement condition,to demonstrate the potential of TCC.This work can not only provide new methodology for regulating the interfacial structure of MXene to enrich the materials library for low-temperature Li-S batteries,but also expand understanding about the role of interfacial structure of sulfur host in Li-S batteries.展开更多
The high-temperature oxidation resistance of AISI 321 stainless steel used in solar thermal power heat exchangers determines its service life.In this study,aluminizing and subsequent laser shock peening(LSP)treatments...The high-temperature oxidation resistance of AISI 321 stainless steel used in solar thermal power heat exchangers determines its service life.In this study,aluminizing and subsequent laser shock peening(LSP)treatments were employed to improve the high-temperature oxidation resistance of AISI 321 stainless steel at 620°C.These two treatments decreased the oxidation rate of AISI 321 steel.Specifically,the optimal oxidation resistance was observed in aluminized steel before oxidation for 144 h owing to the increased entropy of the LSP-treated specimen.After 144 h,LSP-treated steel achieved the best oxidation resistance because of the formation of a protectiveα-Al2O3film.Moreover,the large amount of subgrain boundaries formed on the aluminized layer of the LSP-treated samples could act as short-circuit paths for the outward diffusion of Al,facilitating the rapid nucleation ofα-Al2O3.Meanwhile,the aluminized layer could isolate the contact between the oxidation environment and matrix,thereby decreasing the oxidation rate.Furthermore,the minimum oxidation parabolic constant was calculated for LSP-treated steel(6.45787×10^(-14)),which was 69.18%and 36.36%that of aluminized and 321 steel,respectively,during the entire oxidation process.Therefore,the combination of aluminizing and LSP treatments can improve the high-temperature oxidation resistance of 321 stainless steel,providing a new idea for its surface treatment to achieve a long service life at high temperatures.展开更多
The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size d...The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size distribution of regenerated LiFePO4(R-LFP)becomes narrower,and the D_(50) is reduced from 5.6 to 2.3μm.In addition,the content of Li-Fe antisite defect is reduced from 5.73%to 1.20%,and the F is doped to O(2)site in the structure of R-LFP.Moreover,a coating layer comprising carbon and LiF is formed on the surface of R-LFP because of the decomposition of PVDF.Therefore,the R-LFP demonstrates exceptional Li+diffusion dynamics and conductivity,which delivers a high discharge capacity of 157.3 mA·h/g at 0.1C.And it maintains 92%of its initial capacity after 500 cycles at 1C.展开更多
The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)h...The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.展开更多
The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties o...The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties of various glycol dimethyl ethers are screened,and diglyme(G2)is selected as the sole solvent for the electrolyte.Lithium bis(fluorosulfonyl)imide(LiFSI),a highly dissociative salt,is used as the primary salt;while lithium nitrate(LiNO_(3))and lithium difluorophosphate(LiDFP),which have small ionic sizes and strong binding energies,are added as secondary salts.The resulting electrolyte can modulate the electric double layer structure by NO_(3)^(-) and DFP^(-) on the cathode side,leading to an increased Liþconcentration that is originally repelled by the cathode.Additionally,the oxidation stability of the electrolyte is improved and the formed electrode-electrolyte interphase is more uniform and stable,thereby enhancing the electrochemical performance of the cells.As a result,cells assembled with a total of 1 M ternary lithium salts in G2 solvent can operate at high voltage of 4.4 V.The LijjNCM811 cells maintain 80.2%capacity retention after 270 cycles at room temperature,with an average Coulombic efficiency of 99.5%,and exhibit 88.4%capacity retention after 200 cycles at -30℃.展开更多
基金the financial support from the Key Project of Shaanxi Provincial Natural Science Foundation-Key Project of Laboratory(2025SYS-SYSZD-117)the Natural Science Basic Research Program of Shaanxi(2025JCYBQN-125)+8 种基金Young Talent Fund of Xi'an Association for Science and Technology(0959202513002)the Key Industrial Chain Technology Research Program of Xi'an(24ZDCYJSGG0048)the Key Research and Development Program of Xianyang(L2023-ZDYF-SF-077)Postdoctoral Fellowship Program of CPSF(GZC20241442)Shaanxi Postdoctoral Science Foundation(2024BSHSDZZ070)Research Funds for the Interdisciplinary Projects,CHU(300104240913)the Fundamental Research Funds for the Central Universities,CHU(300102385739,300102384201,300102384103)the Scientific Innovation Practice Project of Postgraduate of Chang'an University(300103725063)the financial support from the Australian Research Council。
文摘Lithium-ion batteries(LIBs),while dominant in energy storage due to high energy density and cycling stability,suffer from severe capacity decay,rate capability degradation,and lithium dendrite formation under low-temperature(LT)operation.Therefore,a more comprehensive and systematic understanding of LIB behavior at LT is urgently required.This review article comprehensively reviews recent advancements in electrolyte engineering strategies aimed at improving the low-temperature operational capabilities of LIBs.The study methodically examines critical performance-limiting mechanisms through fundamental analysis of four primary challenges:insufficient ionic conductivity under cryogenic conditions,kinetically hindered charge transfer processes,Li+transport limitations across the solidelectrolyte interphase(SEI),and uncontrolled lithium dendrite growth.The work elaborates on innovative optimization approaches encompassing lithium salt molecular design with tailored dissociation characteristics,solvent matrix optimization through dielectric constant and viscosity regulation,interfacial engineering additives for constructing low-impedance SEI layers,and gel-polymer composite electrolyte systems.Notably,particular emphasis is placed on emerging machine learning-guided electrolyte formulation strategies that enable high-throughput virtual screening of constituent combinations and prediction of structure-property relationships.These artificial intelligence-assisted rational design frameworks demonstrate significant potential for accelerating the development of next-generation LT electrolytes by establishing quantitative composition-performance correlations through advanced data-driven methodologies.
基金financially supported by the National Natural Science Foundation of China(No.22309067)the Open Project Program of the State Key Laboratory of Materials-Oriented Chemical Engineering,China(No.KL21-05)the Marine Equipment and Technology Institute,Jiangsu University of Science and Technology,China(No.XTCX202404)。
文摘This study focused on improving the cathode performance of Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.15)O_(3-δ)(BSCN)-based perovskite materials through molybdenum(Mo)doping.Pure BSCN and Mo-modified-BSCN—Ea_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.1)Mo_(0.05)O_(3-δ)(B S CNM_(0.05)),Ba_(0.6)Sr_(0.4)Co_(0.85)Nb_(0.05)Mo_(0.1)O_(3-δ)(BSCNM_(0.1)),and Ba_(0.6)Sr_(0.4)Co_(0.85)Mo_(0.15)O_(3-δ)(BSCM)—with Mo doping contents of 5mol%,10mol%,and15mol%,respectively,were successfully prepared using the sol-gel method.The effects of Mo doping on the crystal structure,conductivity,thermal expansion coefficient,oxygen reduction reaction(ORR)activity,and electrochemical performance were systematically evaluated using X-ray diffraction analysis,thermally induced characterization,electrochemical impedance spectroscopy,and single-cell performance tests.The results revealed that Mo doping could improve the conductivity of the materials,suppress their thermal expansion effects,and significantly improve the electrochemical performance.Surface chemical state analysis using X-ray photoelectron spectroscopy revealed that 5mol%Mo doping could facilitate a high adsorbed oxygen concentration leading to enhanced ORR activity in the materials.Density functional theory calculations confirmed that Mo doping promoted the ORR activity in the materials.At an operating temperature of 600℃,the BSCNM_(0.05)cathode material exhibited significantly enhanced electrochemical impedance characteristics,with a reduced area specific resistance of 0.048Ω·cm~2,which was lower than that of the undoped BSCN matrix material by 32.39%.At the same operating temperature,an anode-supported single cell using a BSCNM_(0.05)cathode achieved a peak power density of 1477 mW·cm^(-2),which was 30.71%,56.30%,and 171.50%higher than those of BSCN,BSCNM_(0.1),and B SCM,respectively.The improved ORR activity and electrochemical performance of BSCNM_(0.05)indicate that it can be used as a cathode material in low-temperature solid oxide fuel cells.
文摘This article investigates the low-temperature formation of aluminide coatings on a Ni-base superalloy by pack cementation process. The pack cemented coatings characteristic of high density and homogeneity possess a two-layer structure. The top layer mainly consists of Al3Ni2 and Al3Ni,while the bottom layer of Al3Ni2. Great efforts are made to elucidate the effects of different experimental parameters on the microstructure and the constituent distribution of the coatings. The results show that all the parameters exclusive of the pack activator （NH4Cl） content produce effect on the coating thickness,but do not on the microstructure and the constituent distribution. The pack activator （NH4Cl） content affects neither the coating thickness nor structure and constituent distribution. The parabolic relationship between the coating thickness and the deposition time suggests that the process is diffusion-controlled. Furthermore,the article demonstrates a linear relationship between the coating thickness and the re-ciprocal deposition temperature.
基金Project(51374251)supported by the National Natural Science Foundation of China
文摘A series of low-temperature phase transitions of sodium aluminate solutions were studied by differential scanning calorimetry (DSC) and Raman spectroscopy. The results indicate that NaOH concentration is a primary impact factor for the binary eutectic point and ice melting temperature of sodium aluminate solutions with low NaOH concentration. In addition, the phase transition process of sodium aluminate solutions with low NaOH concentration from 123.15 to 283.15 K is divided into four steps: non-crystal to crystal, ternary eutectic reaction, binary eutectic reaction and ice melt. The projection phase diagram of NaOH-Al(OH)3-H2O system at low temperature was plotted, in which the ternary eutectic temperature for sodium aluminate solutions is 183.15 K.
基金Project supported by the National Natural Science Foundation of China(51464028,51204080 and 51274108)Application Foundation Research of Yunnan Province(2014FB125)
文摘The inherent advantages of ionic liquids （ILs） in electrochemistry have received extensive attention in recent two decades. As a new generation of ILs, non-haloaluminate ILs exhibit better benefits and fewer drawbacks compared to haloaluminate based ILs, which are more qualified for metal electrodeposition, especially reactive metals. In this brief review, the recent developments regard- ing the application of non-haloaluminate ILs as solvents for low-temperature electrodeposition of rare-earth （RE） metals are outlined. In addition, the current problems and an outlook on future research are presented.
基金financial support from the Department of Science and Technology of Jilin Province(20240304104SF,20240304103SF)the Research and Innovation Fund of the Beihua University for the Graduate Student(Major Project 2023012)。
文摘Lithium-ion batteries are widely recognized as prime candidates for energy storage devices.Ethylene carbonate(EC)has become a critical component in conventional commercial electrolytes due to its exceptional film-forming properties and high dielectric constant.However,the elevated freezing point,high viscosity,and strong solvation energy of EC significantly hinder the transport rate of Li^(+)and the desolvation process at low temperatures.This leads to substantial capacity loss and even lithium plating on graphite anodes.Herein,we have developed an efficient electrolyte system specifically designed for lowtemperature conditions,which consists of 1.0 M lithium bis(fluorosulfonyl)imide(LiFSI)in isoxazole(IZ)with fluorobenzene(FB)as an uncoordinated solvent and fluoroethylene carbonate(FEC)as a filmforming co-solvent.This system effectively lowers the desolvation energy of Li^(+)through dipole-dipole interactions.The weak solvation capability allows more anions to enter the solvation sheath,promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs)that enhance the transport rate of Li^(+)while maintaining high ionic conductivity across a broad temperature range.Moreover,the formation of inorganic-dominant interfacial phases on the graphite anode,induced by fluoroethylene carbonate,significantly enhances the kinetics of Li^(+)transport.At a low temperature of-20℃,this electrolyte system achieves an impressive reversible capacity of 200.9 mAh g^(-1)in graphite half-cell,which is nearly three times that observed with conventional EC-based electrolytes,demonstrating excellent stability throughout its operation.
基金support by the National Natural Science Foundation of Inner Mongolia (2022SHZR1885)Natural Science Foundation of Hebei province (E2022402101,E2022402105)。
文摘To completely recover valuable elements and reduce the amount of waste,the impact of phosphoric acid on the decomposition of rare earth,fluorine and phosphorus during cyclic leaching was studied based on the characteristics of low-tempe rature sulfuric acid deco mposition.When a single monazite was leached using 75 wt% H_(2)SO_(4) solution with phosphoric acid,the size and number of monazite particles in the washing slag gradually decrease with the increase in phosphoric acid content in the leaching solution.The monazite phase can hardly be found in the slag when the phosphoric acid content reaches 70 g/L,which indicates that phosphoric acid is favorable for monazite decomposition.The mixed rare earth concentrate was leached by 75 wt% H_(2)SO_(4) containing 70 g/L phosphoric acid,the mineral compositions of the washing slag are only gypsum and unwashed rare earth sulfuric acid.After cyclic leaching of75 wt% H_(2)SO_(4),the mineral compositions of the primary leaching washing slag are mainly undecomposed monazite,rare earth sulfate and calcium sulfate.However,monazite is not found in the mineral phase of the second and third leaching washing slag.The leaching rates of rare earth and phosphorus gradually increase with the increase in cyclic leaching times.In addition,the phosphoric acid content in the leaching solution increases with the increase in the number of cyclic leaching time.However,the rising trend decreases when the phosphoric acid content reaches 50 g/L by adsorption and crystallization of phosphoric acid.A small amount of water can be used to clean the leaching residue before washing to recover the more soluble phosphorus acid according to the difference of dissolution between phosphoric acid and rare earth sulfuric acid.
文摘Because of their excellent low-temperature(−15 to−40℃)tolerance,sodium-ion batteries are emerging as a complement to lithium-ion batteries for use in extremely cold environments(e.g.high-latitude areas).Hard carbon has a high low-voltage sodium storage capacity and a good initial efficiency,making it one of the most promising anode materials for sodium-ion batteries.It has a complex structure,featuring closed pores,nano graphitic domains,and surface functional groups.The sodium storage sites in hard carbon are reviewed as are the widely accepted sodium storage mechanisms.The main factors contributing to the degradation of the good low-temperature performance in hard carbon anodes are considered,including sodium dendrite formation,low ion diffusion rates,and surface-side reactions.Finally,strategies to increase the low-temperature sodium storage performance of hard carbon anodes are summarized,including bulk structure design,and improvements in interfaces and cut-off voltage.Guidance is provided for improving the low-temperature performance of hard carbon anodes to accelerate the development of these batteries.
基金partially supported by the National Natural Science Foundation of China(22479022)Liaoning Revitalization Talents Program(XLYC2007129)。
文摘Aqueous zinc metal batteries(ZMBs)which are environmentally benign and cheap can be used for grid-scale energy storage,but have a short cycling life mainly due to the poor reversibility of zinc metal anodes in mild aqueous electrolytes.A zincophilic carbon(ZC)layer was deposited on a Zn metal foil at 450°C by the up-stream pyrolysis of a hydrogen-bonded supramolecular substance framework,as-sembled from melamine(ME)and cyanuric acid(CA).The zincophilic groups(C=O and C=N)in the ZC layer guide uniform zinc plating/stripping and eliminate dendrites and side reactions.so that assembled symmetrical batteries(ZC@Zn//ZC@Zn)have a long-term service life of 2500 h at 1 mA cm^(−2) and 1 mAh cm^(−2),which is much longer than that of bare Zn anodes(180 h).In addition,ZC@Zn//V2O5 full batteries have a higher capacity of 174 mAh g^(−1) after 1200 cycles at 2 A g^(−1) than a Zn//V_(2)O_(5) counterpart(100 mAh g^(−1)).The strategy developed for the low-temperat-ure deposition of the ZC layer is a new way to construct advanced zinc metal anodes for ZMBs.
基金supported by Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)(No.SML2023SP243)the National Key Research and Development Program of China(No.2022YFC2906100)the National Natural Science Foundation of China(No.92475202)are acknowledged.
文摘Electrochemical metallurgy at low temperature(<473 K)shows promise for the extraction and refinement of metals and alloys in a green and sustainable manner.However,the kinetics of the electrodeposition process is generally slow at low temperature,resulting in large overpotential and low current efficiency.Thus,the application of external physical fields has emerged as an effective strategy for improving the mass and charge transfer processes during electrochemical reactions.This review highlights the challenges associated with low-temperature electrochemical processes and briefly discusses recent achievements in optimizing electrodeposition processes through the use of external physical fields.The regulating effects on the optimization of the electrodeposition process and the strategies for select-ing various external physical fields,including magnetic,supergravity,and ultrasonic fields are summarized from the perspectives of equipment and mechanisms.Finally,advanced methods for in-situ characterization of external physical field-assisted electrodeposition processes are reviewed to gain a deeper understanding of metallic electrodeposition.An in-depth exploration of the mechanism by which external physical fields affect the electrode process is essential for enhancing the efficiency of metal extraction at low temperatures.
基金supported by the Key Research and Development Project of Heilongjiang Province(2022ZX02B01)the Natural Science Foundation Project of Heilongjiang Province(YQ2022C009)the Natural Science Foundation of Shandong Province(K22LB56)。
文摘Maize(Zea mays L.),a globally significant cereal crop,is produced in vast quantities worldwide.However,its growth is severely constrained by low temperatures,particularly during seed germination,which significantly impairs seedling emergence.In this study,genetic diversity across six germination-associated phenotypic traits(RGR,RSL,RTL,RRSA,RRV,and RSVI)of 304 inbred lines was analyzed,to evaluate the capacity of these lines for low-temperature tolerance.Genome-wide association study(GWAS)was carried out by combining six germination-associated phenotypic traits and genotypic data from 30-fold resequencing.The gene ZmBARK1 was identified through integrated GWAS and RNA-seq analyses,and its association with low-temperature tolerance during maize germination was validated by quantitative real-time PCR(qRT-PCR).ZmBARK1,encoding BRASSINOSTEROID INSENSITIVE 1-associated receptor kinase 1,was located on the bin 4.09 region of maize chromosome 4.Amino acid comparison and subcellular localization analyses revealed that ZmBARK1 is highly homologous to AtBAK1 and is localized to the plasma membrane of the cell,which may be involved in regulating brassinosteroid(BR)signaling.In addition,we revealed the role of ZmBARK1 in low-temperature tolerance during maize germination.Compared with wild-type(WT),the ethyl methanesulfonate(EMS)mutant zmbark1 was characterized by substantially enhanced low-temperature tolerance.Overall,these findings provide promising candidate genes,improve low-temperature tolerance in maize,and advance the understanding of regulatory mechanisms underlying maize's response to low-temperature stress.
基金sponsored by the National Natural Science Foundation of China(Nos.52175143,and 51571150).
文摘Magnesium alloys are widely used in aerospace and automotive industries due to their lightweight.However,their poor fatigue performance limits the broader application,especially in dynamic stress environments.This study explores novel coupled pretreatments of free-end largeangle pre-torsion and low-temperature aging to improve the fatigue resistance of rolled ZK60 magnesium alloy.STA(pre-torsion followed by low-temperature aging)and SAT(low-temperature aging followed by pre-torsion)samples were prepared to investigate the influences of pretreatment coupling sequences.The results of microstructure characterization reveal that pre-torsion significantly enhances the formation of tensile twins and introduces a gradient microstructure with increased dislocation density from the center to the edges.STA process resulted in the highest twinning area fraction of 35.2% and a kernel average misorientation of 0.94 at the edge.Mechanical testing demonstrated that the coupled pre-treatment obtained a better combination of strength and plasticity,significantly improved the yield strength in the compression stage,and increased the tensile-compressive yield ratio to>0.9.In the low-cycle fatigue test,the STA samples exhibited lower cyclic mean stress,a smaller cyclic hardening trend,and better hysteretic symmetry,leading to an improvement in fatigue life of up to 256%.The findings suggest that the combined pre-torsion and low-temperature aging treatments offer a promising approach to enhance the mechanical properties and fatigue resistance of ZK60 magnesium alloy,making it suitable for structural applications in demanding environments.
基金supported by the National Natural Science Foundation of China(32272791 and 32072651)the earmarked fund for CARS(CARS-23)+1 种基金the Joint Fund for Innovation Enhancement of Liaoning Province,China(2021-NLTS-11-01)the support program for Young and Middle-aged Scientific and Technological Innovation Talents,China(RC210293)。
文摘Abscisic acid(ABA)plays a key role in promoting the growth and development of plants,as well as mediating the responses of plants to adverse environmental conditions.Here,we measured the photosynthetic capacity of wild-type RR,mutant sitiens(sit),and ABA-pretreated sit tomato seedlings following exposure to low-temperature(LT)stress.We found that the net photosynthetic rate,intercellular carbon dioxide concentration,transpiration rate,and stomatal conductance of sit seedlings were lower than those of RR seedlings under LT stress.The chloroplast width,area,and number of osmiophilic granules were significantly larger in sit seedlings than in RR seedlings,while the chloroplast length/width ratio was significantly lower in sit seedlings than in RR seedlings.The photochemical activity of sit seedlings was lower,and the expression of photosynthesis-related genes in sit seedlings was altered following exposure to LT stress.ABA pretreatment significantly alleviated the above phenomenon.We also conducted an RNA sequencing analysis and characterized the expression patterns of genes in tomato seedlings following exposure to LT stress.We constructed 15 cDNA libraries and identified several differentially expressed genes involved in photosynthesis,plant hormone signaling transduction,and primary and secondary metabolism.Additional analyses of genes encoding transcription factors and proteins involved in photosynthesis-related processes showed pronounced changes in expression under LT stress.Luciferase reporter assay and electrophoretic mobility shift assay revealed that WRKY22 regulates the expression of PsbA.The PSII of WRKY22 and PsbA-silenced plants was inhibited.Our findings indicate that ABA plays a role in regulating the process of photosynthesis and protecting PSII in tomato under LT stress through the WRKY22-PsbA complex.
基金Supported by the National Natural Science Foundation of China(32072352)。
文摘The low-temperature spray drying technology was developed to process instant berry powder with high efficiency and higher anthocyanin retention.The maltodextrin,whey protein and inulin were selected as additives for instant properties formation in berry powder.The effects of inlet air temperature(40℃–80℃),vacuum degree(0.02–0.06 MPa)and additive amount on the physicochemical properties of berry powder were analyzed through solubility,anthocyanin retention and powder yield,based on moisture content and microstructure.The findings indicated that adding maltodextrin to berry enhanced the powder yield and instant solubility.Whey protein,as an additive,provided effective protection for the anthocyanins of berry powder,and the addition less than 10 g·100^(-1) g improved the powder yield.Inulin,as an additive,reduced moisture content of berry powder,which was conducive to the higher anthocyanin retention and solubility.Technique for order preference by similarity to ideal solution(TOPSIS)analysis was conducted to optimize the spray drying parameters for anthocyanin protection and solubility.The addition of 100%maltodextrin enhanced anthocyanin protection and solubility,while maintaining the desired moisture content and powder yield.This approach was used to evaluate the comprehensive quality of berry powder.This research can provide technical guidance for producing berry powder under low-temperature spray drying.
基金financially supported by the Foundation of Hubei Province Key Laboratory of Green Materials for Light Industry,Hubei University of Technology。
文摘The occurrence of tetragonal to monoclinic phase(t→m)transformation in zirconia ceramics under humid ambient conditions induces the low-temperature degradation(LTD).Such t→m transformation could be suppressed by grain size refinement or/and doping small amounts of alumina.Fine-grained dense 3mol%yttria-doped tetragonal zirconia polycrystal(3Y-TZP)ceramics were prepared by pressureless sintering a zirconia powder doped with 0.25wt%alumina.The LTD behaviors of as-prepared 3Y-TZP ceramics were evaluated by accelerated aging at 134℃in water.The samples sintered at 1300℃for 2 h achieve the relative density higher than 99.9%with the average grain size of 147 nm.The 3Y-TZP ceramic exhibits excellent LTD resistance that no t→m transformation takes place after 125 h accelerated aging.Large amounts of defects were observed inside grains evidenced by the high-resolution transmission electron microscopic(HRTEM)analysis.It is proposed that the presence of defects enhances the sintering kinetics and favors the present low-temperature densification.Possible reasons for defects formation were discussed and the mechanical properties of the 3Y-TZP ceramic were reported as well.
基金support from the National Natural Science Foundation of China for financial support(22175054)the Distinguished Project for Scientific Research in Universities of Anhui Province(2024AH020011)+2 种基金the Key Project for Cultivation of Outstanding Young Scholars in Universities of Anhui Province(YQZD2024015)the Key Project of Provincial Natural Science Research Foundation of Anhui Universities,China(No.2022AH050406)the Anhui Province Research Funding for Outstanding Young Talents in Colleges and Universities,China(No.gxyq2022021)。
文摘Low-temperature lithium sulfur(Li-S)batteries have attracted increasing attention,but lithium polysulfide(LiPSs)clu stering and tardy ionic mobility have been challenging issues,which could be exacerbated under high sulfur loading and lean electrolyte.The distinct behaviors of sulfur cathode in lowtemperature Li-S batteries call for special regulations of the sulfur host to improve the electrochemical performances.Here,a three-dimensional Ti_(3)C_(2)micro-cage(TCC)with an interfacial structure modulated by rich curvatures has been fabricated to propel the sulfur electrochemistry at subzero temperatures.Spectroscopic/microscopic analyses and theoretical calculations elucidate that the precipitation of ultrafine Ti-metal particles on the in-situ generated Ti_(3)C_(2)nanoribbons could trigger the self-scrolling of Ti_(3)C_(2)nanoribbons into TCC.Moreover,in-situ ultraviolet-visible spectra collected at low temperature and theoretical calculations verified that the TCC regulated by rich curvatures have effectively alleviated the Li+dissociation barrier,reduced the energy barrier for charge transfer at the electrode-electrolyte interface,and restrained the clustering and shuttling of LiPSs,thus accelerating the electrochemical conversion kinetics of sulfur species at low temperatures.The performances of the carbon-free TCC-S cathode at low temperatures have been also compared from the aspects of cathode configuration and measurement condition,to demonstrate the potential of TCC.This work can not only provide new methodology for regulating the interfacial structure of MXene to enrich the materials library for low-temperature Li-S batteries,but also expand understanding about the role of interfacial structure of sulfur host in Li-S batteries.
基金Supported by National Natural Science Foundation of China(Grant Nos.52075048,51675058,12232004)Hunan Provincial Excellent Youth Project of the Education Department(Grant No.21B0304)+2 种基金Natural Science Foundation of Hunan Province(Grant No.2023JJ30025)Science and Technology Innovation Program of Hunan Province(Grant No.2023RC1058)Scientific Research Innovation Project for Graduate Student of Changsha University of Science and Technology(Grant No.CLSJCX22096)。
文摘The high-temperature oxidation resistance of AISI 321 stainless steel used in solar thermal power heat exchangers determines its service life.In this study,aluminizing and subsequent laser shock peening(LSP)treatments were employed to improve the high-temperature oxidation resistance of AISI 321 stainless steel at 620°C.These two treatments decreased the oxidation rate of AISI 321 steel.Specifically,the optimal oxidation resistance was observed in aluminized steel before oxidation for 144 h owing to the increased entropy of the LSP-treated specimen.After 144 h,LSP-treated steel achieved the best oxidation resistance because of the formation of a protectiveα-Al2O3film.Moreover,the large amount of subgrain boundaries formed on the aluminized layer of the LSP-treated samples could act as short-circuit paths for the outward diffusion of Al,facilitating the rapid nucleation ofα-Al2O3.Meanwhile,the aluminized layer could isolate the contact between the oxidation environment and matrix,thereby decreasing the oxidation rate.Furthermore,the minimum oxidation parabolic constant was calculated for LSP-treated steel(6.45787×10^(-14)),which was 69.18%and 36.36%that of aluminized and 321 steel,respectively,during the entire oxidation process.Therefore,the combination of aluminizing and LSP treatments can improve the high-temperature oxidation resistance of 321 stainless steel,providing a new idea for its surface treatment to achieve a long service life at high temperatures.
基金supported by the National Natural Science Foundation of China(Nos.51874360,51974370,52074360,52122407,52174285)the Innovation and Entrepreneurship Project of Hunan Province,China(No.2020GK4051)+1 种基金the Key R&D Program of Yunan Province,China(No.202103AA080019)the Natural Science Foundation for Distinguished Young Scholars of Hunan Province,China(No.2024JJ2077)。
文摘The morphology,crystal structure,and electrochemical performance of spent LiFePO_(4)(S-LFP)are recovered by one-step low-temperature solid phase sintering.After sintering at 550℃ for 3 h,the secondary particle size distribution of regenerated LiFePO4(R-LFP)becomes narrower,and the D_(50) is reduced from 5.6 to 2.3μm.In addition,the content of Li-Fe antisite defect is reduced from 5.73%to 1.20%,and the F is doped to O(2)site in the structure of R-LFP.Moreover,a coating layer comprising carbon and LiF is formed on the surface of R-LFP because of the decomposition of PVDF.Therefore,the R-LFP demonstrates exceptional Li+diffusion dynamics and conductivity,which delivers a high discharge capacity of 157.3 mA·h/g at 0.1C.And it maintains 92%of its initial capacity after 500 cycles at 1C.
基金supported by the Natural Science Foundation of Guizhou Province(No.ZK 2022-044)the Platform of Science and Technology and Talent Team Plan of Guizhou Province(No.GCC[2023]007)+1 种基金the National Science Foundation of China(Nos.52101010 and 11964006)the Fund of Natural Science Special(Special Post)Research Foundation of Guizhou University(No.2021-018).
文摘The design and development of high-performance anodes pose significant challenges in the construction of next-generation rechargeable lithium-ion batteries(LIBs).Sodium molybdate dihydrate(Na_(2)MoO_(4)·2H_(2)O)has garnered increasing attention due to its cost-effectiveness,non-toxicity and earth abundance.To enhance the Li storage performance of Na_(2)MoO_(4)·2H_(2)O,a crystallographic orientation regulation strategy is proposed in this work.Initially,density functional theory calculations are carried out to demonstrate that the(020)crystal plane of Na_(2)MoO_(4)·2H_(2)O offers the lowest energy barrier for Li^(+)migration.Subsequently,the preferred crystallographic orientation of Na_(2)MoO_(4)·2H_(2)O crystal is tuned through a low-temperature recrystallization method.Furthermore,the microstructure and phase changes of Na_(2)MoO_(4)·2H_(2)O during the lithiation/de-lithiation process are studied using in situ and ex situ XRD tests,ex situ XPS and cyclic voltammetry to unravel its Li^(+)storage mechanism.Upon application as LIBs anode,the Na_(2)MoO_(4)·2H_(2)O single-crystal particles with a preferred(020)surface exhibit superior reversible capacity,high-capacity retention and high cycling stability.The enhanced Li storage performance should be attributed to the regulated crystallographic orientation and small changes in the crystal microstructure during the charge/discharge process,which facilitates Li^(+)migration and bolsters structural stability.Notably,this study introduces a novel concept and a simple synthesis method for the advancement of electrodes in rechargeable batteries.
文摘The poor oxidation stability of ether-based solvents has long been a major challenge limiting their practical application.To enhance the oxidative stability of ether-based electrolytes,the physicochemical properties of various glycol dimethyl ethers are screened,and diglyme(G2)is selected as the sole solvent for the electrolyte.Lithium bis(fluorosulfonyl)imide(LiFSI),a highly dissociative salt,is used as the primary salt;while lithium nitrate(LiNO_(3))and lithium difluorophosphate(LiDFP),which have small ionic sizes and strong binding energies,are added as secondary salts.The resulting electrolyte can modulate the electric double layer structure by NO_(3)^(-) and DFP^(-) on the cathode side,leading to an increased Liþconcentration that is originally repelled by the cathode.Additionally,the oxidation stability of the electrolyte is improved and the formed electrode-electrolyte interphase is more uniform and stable,thereby enhancing the electrochemical performance of the cells.As a result,cells assembled with a total of 1 M ternary lithium salts in G2 solvent can operate at high voltage of 4.4 V.The LijjNCM811 cells maintain 80.2%capacity retention after 270 cycles at room temperature,with an average Coulombic efficiency of 99.5%,and exhibit 88.4%capacity retention after 200 cycles at -30℃.
