As an important sustainable energy source,Li-ion batteries have been widely used in mobile phones,electric vehicles,large-scale energy storage and aerospace.However,due to the inevitable safety risks of traditional li...As an important sustainable energy source,Li-ion batteries have been widely used in mobile phones,electric vehicles,large-scale energy storage and aerospace.However,due to the inevitable safety risks of traditional liquid Li-ion batteries,the use of all-solid-state batteries to replace organic liquid electrolytes has become one of the most effective ways to solve safety problem.Solid-state electrolyte(SSE)is the core part of allsolid-state Li-ion battery,and ideal SSE has the characteristics of high ionic conductivity,wide enough electrochemical stability window,suitable mechanical strength and excellent chemical stability,the first among which is particularly an essential prerequisite.While,so far only a few SSEs exhibit the Li ionic conductivities higher than 10^(-4) S/cm at room temperature.展开更多
The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining...The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2)battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.展开更多
Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.He...Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.Herein,a universal fast zinc-ion diffusion layer on a three-dimensional(3 D)mesh structure model is demonstrated to effectively improve Zn plating/stripping reversibility.The fast ion diffusion alloy layer accelerates the Zn^(2+)migration in an orderly manner to homogenize Zn^(2+)flux and overcomes the defects of the commercial mesh substrate,effectively avoiding dendrite growth and side reactions.Consequently,the proof-of-concept silver-zinc alloy modified stainless steel mesh delivers superb reversibility with the high coulombic efficiency over 99.4%at 4 mA cm^(-2)after 1600 cycles and excellent reliability of over 830 h at 1 mA cm^(-2),Its feasibility is also evidenced in commercial zinc ion hybrid capacitors with activated carbon as the cathode.This work enriches the fundamental comprehension of fast zinc-ion diffusion layer combined with a 3 D substrate on the Zn deposition and opens a universal approach to design advanced host for Zn electrodes in zinc ion hybrid capacitors.展开更多
In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata （CA）-based model is proposed. The p...In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata （CA）-based model is proposed. The process of chloride ion diffusion is analyzed by the CA-based method and a nonlinear solution of the Fick＇s second law is obtained. Considering the impact of various factors such as stress states, temporal and spatial variability of diffusion parameters and water-cement ratio on the process of chloride ion diffusion, the model of chloride ion diffusion under multi-factor coupling actions is presented. A chloride ion penetrating experiment reported in the literature is used to prove the effectiveness and reasonability of the present method, and a T-type beam is taken as an illustrative example to analyze the process of chloride ion diffusion in practical application. The results indicate that CA-based method can simulate the diffusion of chloride ion in the concrete structures with acceptable precision.展开更多
Dielectric relaxation method was employed to study the properties of oxygen ion diffusion and phase transition in the oxide-ion conductors （Lal-xLnx）2Mo209 （Ln=Nd, Gd, x=0.05-0.25）. Two dielectric loss peaks were ...Dielectric relaxation method was employed to study the properties of oxygen ion diffusion and phase transition in the oxide-ion conductors （Lal-xLnx）2Mo209 （Ln=Nd, Gd, x=0.05-0.25）. Two dielectric loss peaks were observed： peak Pd at about 600 K and peak P5 around 720 K. Peak Pd is a relaxational peak and associated with the short-range diffusion of oxygen ions, while peak P5 hardly changes its position and dramatically decreases in height with increasing frequency, exhibiting non-relaxational nature. With increasing Ln^3＋ concentration, the heights of peak Ph and Pd increase at first and then decrease after passing a maximum at 15% doping. It is suggested that peak P5 is related to the phase transition of a static disordered state to a dynamic disordered state in oxygen ions/vacancies distribution. It is found that the 15%Gd or 15%Nd doped La2Mo209 samples exhibit the highest conductivity in accordance with the highest height of peak Pd at this doping content.展开更多
The durability performance of reinforced concrete(RC)building structures is significantly affected by the corrosion of the steel reinforcement due to chloride penetration,thus,the chloride ion diffusion coefficient sh...The durability performance of reinforced concrete(RC)building structures is significantly affected by the corrosion of the steel reinforcement due to chloride penetration,thus,the chloride ion diffusion coefficient should be investigated through experiments or theoretical equations to assess the durability of an RC structure.This study aims to predict the chloride ion diffusion coefficient of concrete,a heterogeneous material.A convolutional neural network(CNN)-based regression model that learns the condition of the concrete surface through deep learning,is developed to efficiently obtain the chloride ion diffusion coefficient.For the model implementation to determine the chloride ion diffusion coefficient,concrete mixes with w/c ratios of 0.33,0.40,0.46,0.50,0.62,and 0.68,are cured for 28 days;subsequently,the surface image data of the specimens are collected.Finally,the proposed model predicts the chloride ion diffusion coefficient using the concrete surface image data and exhibits an error of approximately 1.5E−12 m^(2)/s.The results suggest the applicability of proposed model to the field of facility maintenance for estimating the chloride ion diffusion coefficient of concrete using images.展开更多
Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high safety.However,their performance and sustainability are significantly hi...Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high safety.However,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn(H_(2)O)_(6)^(2+)solvation shell.Herein,learnt from self-generated solid electrolyte interphase (SEI) in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface (ZNB@Zn),acting as a rapid desolvation promotor.The zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical calculations.Consequently,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility (99.54%) even under high current density and depth of discharge conditions.Meanwhile,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g^(-1)and outstanding rate performance up to 10 A g^(-1).The large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.展开更多
Transition metal compounds(TMCs)with high theoretical capacity have been considered as promising battery-type electrode materials for hybrid supercapacitors(HSCs),yet they often encounter low rate capability and poor ...Transition metal compounds(TMCs)with high theoretical capacity have been considered as promising battery-type electrode materials for hybrid supercapacitors(HSCs),yet they often encounter low rate capability and poor cycling performance.Herein,the NiCoSe2 nanoparticles strongly bonded on the N-doped SiC nanowires(N-S@b-NCS)with Ni/Co-N bonds in their interfaces are firstly constructed via an electrodeposition method.Theoretical calculations indicate that the unique interfacial chemical bonding with built-in electric field can not only significantly facilitate charge transfer and reduce the ion diffusion barrier,but also effectively guarantee structure integration induced by the timely release of stress concentration.Benefiting from the advantages,the achieved N-S@b-NCS exhibits high specific capacity of 254.4 mAh·g^(-1)at 1 A·g^(-1)and still retains 183.2 mAh·g^(-1)even at 100 A·g^(-1),as well as outstanding cycling stability with~90%capacity retention after 30,000 cycles.Additionally,a hybrid supercapacitor assembled by the obtained N-S@b-NCS displays a high energy density of 71.4 Wh·kg^(-1)at 16 kW·kg^(-1)and excellent durability.This work provides a creative strategy for how to construct the bonded interface with ions diffusion highway and long-term cycling stability,which can greatly push the large-scale applications of the TMCs.展开更多
The in-depth study of the transport properties of the solid electrolyte interface(SEI)is crucial for the development of ultra-high-rate,and long lifespan sodium-ion batteries(SIBs).However,there remains a lack of theo...The in-depth study of the transport properties of the solid electrolyte interface(SEI)is crucial for the development of ultra-high-rate,and long lifespan sodium-ion batteries(SIBs).However,there remains a lack of theoretical investigation into the transport mechanisms of the main inorganic components of the SEI,namely Na F,Na_(2)O,and Na_(2)CO_(3).To address this research gap,we performed classical molecular dynamics simulations in this work to study the diffusion mechanisms of sodium ions in these inorganic components of the SEI,with special emphasis on the impact of the amorphous SEI environment on the diffusion behavior of sodium ions.The results have shown that amorphous SEI components significantly enhance the diffusion rate of sodium ions at room temperature compared to crystalline components.Within these amorphous SEI components,we reveal that the diffusion coefficients of sodium ions in amorphous Na_(2)O and Na_(2)CO_(3)are more than an order of magnitude higher than that of Na F,suggesting that amorphous Na_(2)O and Na_(2)CO_(3)are more effective in facilitating the Na ion diffusion.Analysis of the local atomic structure indicates that the amorphous local structures are dominant in Na_(2)O and Na_(2)CO_(3)at room temperature,maintaining a disordered amorphous phase.In contrast,amorphous Na F undergoes a spontaneously transformation into an ordered structure,exhibiting crystalline characteristics that restrict the diffusion of sodium ions.In summary,our work provides atomic insights into the impact of local amorphous environments on Na ion diffusion in SEI and suggests that amorphous SEI components play a critical role in improving battery performance.展开更多
Lithium metal stands out as an exceptionally promising anode material,boasting an extraordinarily high theoretical capacity and impressive energy density.Despite these advantageous characters,the issues of dendrite fo...Lithium metal stands out as an exceptionally promising anode material,boasting an extraordinarily high theoretical capacity and impressive energy density.Despite these advantageous characters,the issues of dendrite formation and volume expansion of lithium metal anodes lead to performance decay and safety concerns,significantly impeding their advancement towards widespread commercial viability.Herein,a lithium-rich Li-B-In composite anode with abundant lithophilic sites and outstanding structural stability is reported to address the mentioned challenges.The evenly distributed Li-In alloy in the bulk phase of anodes act as mixed ion/electron conductors and nucleation sites,facilitating accelerated Li ions transport dynamics and suppressing lithium dendrite formation.Additionally,these micron-sized Li-In particles in LiB fibers framework can enhance overall structural integrity and provide sufficient interior space to accommodate the volume changes during cycling.The electrochemical performance of Li-B-In composite anode exhibits long-term cyclability,superior rate performance and high-capacity retention.This work confirms that the synergy between a 3 D skeleton and hetero-metallic lithiophilic sites can achieve stable and durable lithium metal anodes,offering innovative insights for the practical deployment of lithium metal batteries.展开更多
Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable development.Hydroelectricity generation from ubiquitous and spontaneous phase transitions between liquid and gas...Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable development.Hydroelectricity generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy crisis.Fibrous materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first introduced.Then,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are demonstrated.Afterward,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in detail.Moreover,the potential applications including power supply,energy storage,electrical sensor,and information expression are also discussed.Finally,some existing challenges are considered and prospects for future development are sincerely proposed.展开更多
Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting...Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.展开更多
The feasibility of using different generations of recycled fine aggregate（RFA） in structural concrete in a chloride environment was evaluated by studying the performance of the RFA and the corresponding concrete. Th...The feasibility of using different generations of recycled fine aggregate（RFA） in structural concrete in a chloride environment was evaluated by studying the performance of the RFA and the corresponding concrete. The different generations of RFA were recycled by following the cycle of ‘concrete-waste concrete-fine aggregate-concrete＇. The properties of three generations of repeatedly recycled fine aggregate（RRFA） were systematically investigated, and we focused on the compressive strength and splitting tensile strength and chloride ion permeability of the related structural concretes with 25%, 75%, and 100% replacement of natural fine aggregates with RFA. The results indicated that the quality of RRFA presents a trend of slow deterioration, but the overall performance of all RRFA still fulfils the quality requirements of recycled fine aggregate for structural concrete. All RRFA concretes achieved the target compressive strength of 40 MPa after 28 days except for the second generation of the recycled aggregate concrete and the third generation of the recycled aggregate concrete with 100% replacement, and all the concrete mixes achieved the target compressive strength after 90 days. The insights obtained in this study demonstrate the feasibility of using at least three generations of RRFA for the production of normal structural concrete with a design service life of 100 years in a chloride environment.展开更多
The lithium-ion batteries are recognized as the most promising energy storage system,but it still does not meet the power requirements of electric vehicle batteries owing to low volumetric energy density with the trad...The lithium-ion batteries are recognized as the most promising energy storage system,but it still does not meet the power requirements of electric vehicle batteries owing to low volumetric energy density with the traditional graphite electrode system.In this study,we report the development of a novel electrode system fabricated by implantation of a solid electrolyte interphase(SEI)layer on the graphite surface.The SEI-implanted graphite electrode is made using a lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)-based electrolyte and cycled with a lithium tetrafluoroborate LiBF4-based electrolyte.This new electrode system shows significantly enhanced electrochemical properties owing to the rapid and efficient diffusion of Li ions through the SEI layer between the electrolyte and electrode.This graphite electrode with its pre-formed SEI layer achieves a reversible capacity of 357 mAh g^-1 at 0.5 C after 50 cycles,which is significantly higher than that of commercial lithium-ion battery systems constructed with LiPF6(312mAh g^-1).The resulting unique electrode system could present a new avenue in SEI research for highperformance lithium-ion batteries.展开更多
Promoting inorganic-rich solid-electrolyte interphase (SEI) formation by constructing anion-rich solvated structures is a promising strategy for improving the long-term cycling of lithium-metal batteries.However,the i...Promoting inorganic-rich solid-electrolyte interphase (SEI) formation by constructing anion-rich solvated structures is a promising strategy for improving the long-term cycling of lithium-metal batteries.However,the increase of anions within the solvated structure inevitably reduces the coordination of Li^(+) with the solvent,which leads to a low lithium diffusion coefficient and a decreased lithium conductivity.Here,high entropy electrolyte is achieved by increasing the molecular diversity in electrolyte.Multiple anions (TFSI^(-),FSI^(-),NO_(3)^(-) and PF_(6)^(-)) presented in entropy electrolyte individually coordinate with Li^(+),creating a diverse and anion-rich solvation structure.The large variety of solvation structures leads to a diversified Li^(+) diffusion barriers in the electrolyte,which results in the increase of channels available for Li^(+) diffusion.Thus,three-dimensional diffusion with high Li^(+) diffusion coefficient occurs in HE electrolytes.Furthermore,the anion-rich solvation structures promote the formation of the inorganic-rich SEI.As a result,over 2000 h of reversible Li plating/stripping with a low overpotential less than 27 mV is achieved in Li||Li cell using electrolyte modified by high-entropy strategy.Besides,the Li||LFP full cell with a negative capacity/positive capacity (N/P) ratio of 4.52 exhibits remarkably enhanced cycling stability,retaining 83.6% of its initial capacity after 150 cycles.This strategy offers a novel approach for accelerating Li^(+) transport kinetics and constructing stable SEI in lithium metal batteries.展开更多
It is necessary to pay more attention to the durability of concrete undergoing freeze-thaw cycles and seawater attack simultaneously.Investigated are the effects of water-binder ratio,fly ash（FA）contents and air-ent...It is necessary to pay more attention to the durability of concrete undergoing freeze-thaw cycles and seawater attack simultaneously.Investigated are the effects of water-binder ratio,fly ash（FA）contents and air-entraining agent on resistance to frost and chloride diffusion of marine concrete blended with FA in natural seawater.The results show that fly ash does not improve the frost resistance of concrete but can improve its resistance to chloride diffusion by addition of less than 30%.The resistance to frost and chloride diffusion of FA concrete can be improved with the decrease of water-binder ratio,and FA may improve both of them simultaneously only being mixed with air-entraining agent.A ratio（named as R）of the frost-resisting durability factor to chloride diffusion coefficient can be used to evaluate the durability of marine concrete.Scanning electron microscope（SEM）analyses are consistent with the evaluations by the value of R.展开更多
Recycled large aggregate self-compacting concrete (RLA-SCC) within multiple weak areas. These weak areas have poor resistance to chloride ion erosion, which affects the service life of RLA-SCC in the marine environmen...Recycled large aggregate self-compacting concrete (RLA-SCC) within multiple weak areas. These weak areas have poor resistance to chloride ion erosion, which affects the service life of RLA-SCC in the marine environment. A three-dimensional multi-phase mesoscopic numerical model of RLA-SCC was established to simulate the chloride ions transportation in concrete. Experiments of RLA-SCC immersing in chloride solution were carried out to verify the simulation results. The effects of recycled large aggregate (RLA) content and RLA particle size on the service life of concrete were explored. The results indicate that the mesoscopic numerical simulation results are in good agreement with the experimental results. At the same depth, the closer to the surface of the RLA, the greater the chloride ion concentration. The service life of RLA-SCC in marine environment decreases with the increase of RLA content. Compared with the service life of 20% content, the service life of 25% and 30% content decreased by 20% and 42% respectively. Increasing the particle size of RLA can effectively improve the service life of RLA-SCC in chloride environment. Compared with the service life of 50 mm particle size, the service life of 70 mm and 90 mm increased by 61% and 163%, respectively. .展开更多
In situ NMR measurements of the diffusion coefficients,including an estimate of signal strength,of lithium ion conductor using diffusion-weighting pulse sequence are performed in this study.A cascade bilinear model is...In situ NMR measurements of the diffusion coefficients,including an estimate of signal strength,of lithium ion conductor using diffusion-weighting pulse sequence are performed in this study.A cascade bilinear model is proposed to estimate the diffusion sensitivity factors of pulsed-field gradient using prior information of the electrochemical performance and Arrhenius constraint.The model postulates that the active lithium nuclei participating electrochemical reaction are relevant to the NMR signal intensity,when discharge rate or temperature condition is varying.The electrochemical data and the NMR signal strength show a highly fit with the proposed model according our simulation and experiments.Furthermore,the diffusion time is constrained by temperature based on Arrhenius equation of reaction rates dependence.An experimental calculation of Li_4Ti_5O_（12）（LTO）/carbon nanotubes（CNTs） with the electrolyte evaluating at 20 ℃ is presented,which the b factor is estimated by the discharge rate.展开更多
Sodium(Na)metal batteries with a high volumetric energy density that can be operated at high rates are highly desirable.However,an uneven Na-ion migration in bulk Na anodes leads to localized deposition/dissolution of...Sodium(Na)metal batteries with a high volumetric energy density that can be operated at high rates are highly desirable.However,an uneven Na-ion migration in bulk Na anodes leads to localized deposition/dissolution of sodium during high-rate plating/stripping behaviors,followed by severe dendrite growth and loose stacking.Herein,we engineer the Na hybrid anode with sodiophilic Na_(3)Bi-penetration to develop the abundant phase-boundary ionic transport channels.Compared to intrinsic Na,the reduced adsorption energy and ion-diffusion barrier on Na_(3)Bi ensure even Na^(+)nucleation and rapid Na^(+)migration within the hybrid electrode,leading to uniform deposition and dissolution at high current densities.Furthermore,the bismuthide enables compact Na deposition within the sodiophilic framework during cycling,thus favoring a high volumetric capacity.Consequently,the obtained anode was endowed with a high current density(up to 5 mA∙cm^(−2)),high areal capacity(up to 5 mA∙h∙cm^(−2)),and long-term cycling stability(up to 2800 h at 2 mA∙cm^(−2)).展开更多
Mesoporous LiFePO4/C composites containing 80 wt% of highly dispersed LiFePO4 nanoparticles(4-6 nm) were fabricated using bimodal mesoporous carbon(BMC) as continuous conductive networks. The unique pore structure of ...Mesoporous LiFePO4/C composites containing 80 wt% of highly dispersed LiFePO4 nanoparticles(4-6 nm) were fabricated using bimodal mesoporous carbon(BMC) as continuous conductive networks. The unique pore structure of BMC not only promises good particle connectivity for LiFePO4, but also acts as a rigid nano-confinement support that controls the particle size. Furthermore, the capacities were investigated respectively based on the weight of LiFePO4 and the whole composite. When calculated based on the weight of the whole composite, it is 120 mAh·g-1at 0.1 C of the high loading electrode and 42 mAh·g-1at 10 C of the low loading electrode. The electrochemical performance shows that high LiFePO4 loading benefits large tap density and contributes to the energy storage at low rates, while the electrode with low content of LiFePO4 displays superior high rate performance, which can mainly be due to the small particle size, good dispersion and high utilization of the active material, thus leading to a fast ion and electron diffusion.展开更多
基金supported by the Natural Science Foundation of Shandong Province(No.ZR2020MB049)the Shandong Laboratory of Advanced Materials and Green Manufacturing at Yantai(No.AMGM2023A07)。
文摘As an important sustainable energy source,Li-ion batteries have been widely used in mobile phones,electric vehicles,large-scale energy storage and aerospace.However,due to the inevitable safety risks of traditional liquid Li-ion batteries,the use of all-solid-state batteries to replace organic liquid electrolytes has become one of the most effective ways to solve safety problem.Solid-state electrolyte(SSE)is the core part of allsolid-state Li-ion battery,and ideal SSE has the characteristics of high ionic conductivity,wide enough electrochemical stability window,suitable mechanical strength and excellent chemical stability,the first among which is particularly an essential prerequisite.While,so far only a few SSEs exhibit the Li ionic conductivities higher than 10^(-4) S/cm at room temperature.
基金financial support from the Center for Coastal Climate Resilience of the University of California,Santa Cruz(UCSC)This work was performed under the auspices of the US Department of Energy by Lawrence Livermore National Laboratory under Contract No.DE-AC52-07NA27344 and supported by Laboratory Directed Research and Development award 23-SI-002.IM release number:LLNL-JRNL-862347。
文摘The architectural design of electrodes offers new opportunities for next-generation electrochemical energy storage devices(EESDs)by increasing surface area,thickness,and active materials mass loading while maintaining good ion diffusion through optimized electrode tortuosity.However,conventional thick electrodes increase ion diffusion length and cause larger ion concentration gradients,limiting reaction kinetics.We demonstrate a strategy for building interpenetrated structures that shortens ion diffusion length and reduces ion concentration inhomogeneity.This free-standing device structure also avoids short-circuiting without needing a separator.The feature size and number of interpenetrated units can be adjusted during printing to balance surface area and ion diffusion.Starting with a 3D-printed interpenetrated polymer substrate,we metallize it to make it conductive.This substrate has two individually addressable electrodes,allowing selective electrodeposition of energy storage materials.Using a Zn//MnO_(2)battery as a model system,the interpenetrated device outperforms conventional separate electrode configurations,improving volumetric energy density by 221%and exhibiting a higher capacity retention rate of 49%compared to 35%at temperatures from 20 to 0℃.Our study introduces a new EESD architecture applicable to Li-ion,Na-ion batteries,supercapacitors,etc.
基金financially supported by the National Natural Science Foundation of China(51901249,U1904216)。
文摘Although aqueous zinc ion hybrid capacitors have advantageous integration of batteries and supercapacitors,they still suffer from the inherent problems of dendrite growth and interfacial side reactions on Zn anodes.Herein,a universal fast zinc-ion diffusion layer on a three-dimensional(3 D)mesh structure model is demonstrated to effectively improve Zn plating/stripping reversibility.The fast ion diffusion alloy layer accelerates the Zn^(2+)migration in an orderly manner to homogenize Zn^(2+)flux and overcomes the defects of the commercial mesh substrate,effectively avoiding dendrite growth and side reactions.Consequently,the proof-of-concept silver-zinc alloy modified stainless steel mesh delivers superb reversibility with the high coulombic efficiency over 99.4%at 4 mA cm^(-2)after 1600 cycles and excellent reliability of over 830 h at 1 mA cm^(-2),Its feasibility is also evidenced in commercial zinc ion hybrid capacitors with activated carbon as the cathode.This work enriches the fundamental comprehension of fast zinc-ion diffusion layer combined with a 3 D substrate on the Zn deposition and opens a universal approach to design advanced host for Zn electrodes in zinc ion hybrid capacitors.
基金the National Natural Science Foundation of China (No.51178305)Key Projects in the Science & Technology Pillar Program of Tianjin (No.11ZCKFSF00300)
文摘In order to accurately simulate the diffusion of chloride ion in the existing concrete bridge and acquire the precise chloride ion concentration at given time, a cellular automata （CA）-based model is proposed. The process of chloride ion diffusion is analyzed by the CA-based method and a nonlinear solution of the Fick＇s second law is obtained. Considering the impact of various factors such as stress states, temporal and spatial variability of diffusion parameters and water-cement ratio on the process of chloride ion diffusion, the model of chloride ion diffusion under multi-factor coupling actions is presented. A chloride ion penetrating experiment reported in the literature is used to prove the effectiveness and reasonability of the present method, and a T-type beam is taken as an illustrative example to analyze the process of chloride ion diffusion in practical application. The results indicate that CA-based method can simulate the diffusion of chloride ion in the concrete structures with acceptable precision.
基金This work was supported by the Ningbo Civic Natural Science Foundation （No.2006A610057）, the Ningbo Civic Project of International Cooperation （No.2006B100080）, Zhejiang Provincial Project of International Cooperation （No.2007C24022）, and the National Natural Science Foundation of China （No.50672100 and No.50702061）.
文摘Dielectric relaxation method was employed to study the properties of oxygen ion diffusion and phase transition in the oxide-ion conductors （Lal-xLnx）2Mo209 （Ln=Nd, Gd, x=0.05-0.25）. Two dielectric loss peaks were observed： peak Pd at about 600 K and peak P5 around 720 K. Peak Pd is a relaxational peak and associated with the short-range diffusion of oxygen ions, while peak P5 hardly changes its position and dramatically decreases in height with increasing frequency, exhibiting non-relaxational nature. With increasing Ln^3＋ concentration, the heights of peak Ph and Pd increase at first and then decrease after passing a maximum at 15% doping. It is suggested that peak P5 is related to the phase transition of a static disordered state to a dynamic disordered state in oxygen ions/vacancies distribution. It is found that the 15%Gd or 15%Nd doped La2Mo209 samples exhibit the highest conductivity in accordance with the highest height of peak Pd at this doping content.
基金This work was supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(NRF-2021R1A2C2007904).
文摘The durability performance of reinforced concrete(RC)building structures is significantly affected by the corrosion of the steel reinforcement due to chloride penetration,thus,the chloride ion diffusion coefficient should be investigated through experiments or theoretical equations to assess the durability of an RC structure.This study aims to predict the chloride ion diffusion coefficient of concrete,a heterogeneous material.A convolutional neural network(CNN)-based regression model that learns the condition of the concrete surface through deep learning,is developed to efficiently obtain the chloride ion diffusion coefficient.For the model implementation to determine the chloride ion diffusion coefficient,concrete mixes with w/c ratios of 0.33,0.40,0.46,0.50,0.62,and 0.68,are cured for 28 days;subsequently,the surface image data of the specimens are collected.Finally,the proposed model predicts the chloride ion diffusion coefficient using the concrete surface image data and exhibits an error of approximately 1.5E−12 m^(2)/s.The results suggest the applicability of proposed model to the field of facility maintenance for estimating the chloride ion diffusion coefficient of concrete using images.
基金National Key R&D Program of China (2021YFA1201503)National Natural Science Foundation of China (21972164, 22279161, 12264038, 22309144)+4 种基金Natural Science Foundation of Jiangsu Province (BK. 20210130)China Postdoctoral Science Foundation (2023M733189)Jiangsu Double-Innovation PhD Program in 2022 (JSSCBS20221241)Senior Talents Fund of Jiangsu University (5501220014)fellowship funding provided by the Alexander von Humboldt Foundation。
文摘Rechargeable aqueous zinc-metal batteries (AZMBs) are promising candidates for large-scale energy storage systems due to their low cost and high safety.However,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn(H_(2)O)_(6)^(2+)solvation shell.Herein,learnt from self-generated solid electrolyte interphase (SEI) in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface (ZNB@Zn),acting as a rapid desolvation promotor.The zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical calculations.Consequently,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility (99.54%) even under high current density and depth of discharge conditions.Meanwhile,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g^(-1)and outstanding rate performance up to 10 A g^(-1).The large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.
基金supported by the National Natural Science Foundation of China(Nos.52072196,52202262,22379081,and 22379080)the Natural Science Foundation of Shandong Province(Nos.ZR202108180009 and ZR2023QE059).
文摘Transition metal compounds(TMCs)with high theoretical capacity have been considered as promising battery-type electrode materials for hybrid supercapacitors(HSCs),yet they often encounter low rate capability and poor cycling performance.Herein,the NiCoSe2 nanoparticles strongly bonded on the N-doped SiC nanowires(N-S@b-NCS)with Ni/Co-N bonds in their interfaces are firstly constructed via an electrodeposition method.Theoretical calculations indicate that the unique interfacial chemical bonding with built-in electric field can not only significantly facilitate charge transfer and reduce the ion diffusion barrier,but also effectively guarantee structure integration induced by the timely release of stress concentration.Benefiting from the advantages,the achieved N-S@b-NCS exhibits high specific capacity of 254.4 mAh·g^(-1)at 1 A·g^(-1)and still retains 183.2 mAh·g^(-1)even at 100 A·g^(-1),as well as outstanding cycling stability with~90%capacity retention after 30,000 cycles.Additionally,a hybrid supercapacitor assembled by the obtained N-S@b-NCS displays a high energy density of 71.4 Wh·kg^(-1)at 16 kW·kg^(-1)and excellent durability.This work provides a creative strategy for how to construct the bonded interface with ions diffusion highway and long-term cycling stability,which can greatly push the large-scale applications of the TMCs.
基金financial support from the National Key Research and Development Project of China(No.2022YFE0113800)the Natural Science Foundation of Zhejiang Province(No.LY23E020010)+1 种基金the National Natural Science Foundation of China(Nos.U21A20174 and 52225208)the funding from China Postdoctoral Science Foundation(No.2023M743098)。
文摘The in-depth study of the transport properties of the solid electrolyte interface(SEI)is crucial for the development of ultra-high-rate,and long lifespan sodium-ion batteries(SIBs).However,there remains a lack of theoretical investigation into the transport mechanisms of the main inorganic components of the SEI,namely Na F,Na_(2)O,and Na_(2)CO_(3).To address this research gap,we performed classical molecular dynamics simulations in this work to study the diffusion mechanisms of sodium ions in these inorganic components of the SEI,with special emphasis on the impact of the amorphous SEI environment on the diffusion behavior of sodium ions.The results have shown that amorphous SEI components significantly enhance the diffusion rate of sodium ions at room temperature compared to crystalline components.Within these amorphous SEI components,we reveal that the diffusion coefficients of sodium ions in amorphous Na_(2)O and Na_(2)CO_(3)are more than an order of magnitude higher than that of Na F,suggesting that amorphous Na_(2)O and Na_(2)CO_(3)are more effective in facilitating the Na ion diffusion.Analysis of the local atomic structure indicates that the amorphous local structures are dominant in Na_(2)O and Na_(2)CO_(3)at room temperature,maintaining a disordered amorphous phase.In contrast,amorphous Na F undergoes a spontaneously transformation into an ordered structure,exhibiting crystalline characteristics that restrict the diffusion of sodium ions.In summary,our work provides atomic insights into the impact of local amorphous environments on Na ion diffusion in SEI and suggests that amorphous SEI components play a critical role in improving battery performance.
基金Project(2023YFC3905904)supported by the National Key Research and Development Program,ChinaProject(2220197000221)supported by the Team of Foshan National Hi-Tech Industrial Development Zone Industrialization Entrepreneurial Teams Program,ChinaProject(2024ZZTS0373)supported by the Central South University Graduate Student Autonomous Exploration Innovative Programme,China。
文摘Lithium metal stands out as an exceptionally promising anode material,boasting an extraordinarily high theoretical capacity and impressive energy density.Despite these advantageous characters,the issues of dendrite formation and volume expansion of lithium metal anodes lead to performance decay and safety concerns,significantly impeding their advancement towards widespread commercial viability.Herein,a lithium-rich Li-B-In composite anode with abundant lithophilic sites and outstanding structural stability is reported to address the mentioned challenges.The evenly distributed Li-In alloy in the bulk phase of anodes act as mixed ion/electron conductors and nucleation sites,facilitating accelerated Li ions transport dynamics and suppressing lithium dendrite formation.Additionally,these micron-sized Li-In particles in LiB fibers framework can enhance overall structural integrity and provide sufficient interior space to accommodate the volume changes during cycling.The electrochemical performance of Li-B-In composite anode exhibits long-term cyclability,superior rate performance and high-capacity retention.This work confirms that the synergy between a 3 D skeleton and hetero-metallic lithiophilic sites can achieve stable and durable lithium metal anodes,offering innovative insights for the practical deployment of lithium metal batteries.
基金funding support from the National Key Research and Development Program of China(No.2022YFB3805800)the National Natural Science Foundation of China(52173059)+1 种基金The Major Basic Research Project of the Natural Science Foundation of the Jiangsu Higher Education Institutions(21KJA540002)Jiangsu Funding Program for Excellent Postdoctoral Talent(2022ZB555).
文摘Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable development.Hydroelectricity generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy crisis.Fibrous materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first introduced.Then,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are demonstrated.Afterward,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in detail.Moreover,the potential applications including power supply,energy storage,electrical sensor,and information expression are also discussed.Finally,some existing challenges are considered and prospects for future development are sincerely proposed.
基金the financial support of the National Natural Science Foundation of China(No.22205165).
文摘Moisture-enabled electricity generation(MEG)has emerged as a promising sustainable energy harvesting technology,comparable to photovoltaics,thermoelectrics,and triboelectrics[1].MEGs generate electricity by converting the chemical potential of moisture into electric energy through interactions with hygroscopic materials and nanostructured interfaces.Unlike solar or thermal harvesters,MEGs operate continuously by utilizing ubiquitous atmospheric moisture,granting them unique spatial and temporal adaptability.Despite nearly a decade of progress and the exploration of diverse material systems for MEG,the overall output power remains significantly limited due to inherently low charge carrier concentrations and restricted ion diffusion fluxes[2].As a result,standalone MEG devices often deliver low and unstable output,limiting practical applications.To enhance performance and versatility,recent efforts have explored hybridization of MEG with other ambient energy sources such as triboelectric or thermoelectric effects.
基金Funded by the National Natural Science Foundation of China(No.51278073)State Key Laboratoryfor GeoMechanics and Deep Underground Engineering,China University of Mining&Technology(No.SKLGDUEK1704)
文摘The feasibility of using different generations of recycled fine aggregate（RFA） in structural concrete in a chloride environment was evaluated by studying the performance of the RFA and the corresponding concrete. The different generations of RFA were recycled by following the cycle of ‘concrete-waste concrete-fine aggregate-concrete＇. The properties of three generations of repeatedly recycled fine aggregate（RRFA） were systematically investigated, and we focused on the compressive strength and splitting tensile strength and chloride ion permeability of the related structural concretes with 25%, 75%, and 100% replacement of natural fine aggregates with RFA. The results indicated that the quality of RRFA presents a trend of slow deterioration, but the overall performance of all RRFA still fulfils the quality requirements of recycled fine aggregate for structural concrete. All RRFA concretes achieved the target compressive strength of 40 MPa after 28 days except for the second generation of the recycled aggregate concrete and the third generation of the recycled aggregate concrete with 100% replacement, and all the concrete mixes achieved the target compressive strength after 90 days. The insights obtained in this study demonstrate the feasibility of using at least three generations of RRFA for the production of normal structural concrete with a design service life of 100 years in a chloride environment.
基金supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science and ICT(NRF-2019R1A2C2088174)。
文摘The lithium-ion batteries are recognized as the most promising energy storage system,but it still does not meet the power requirements of electric vehicle batteries owing to low volumetric energy density with the traditional graphite electrode system.In this study,we report the development of a novel electrode system fabricated by implantation of a solid electrolyte interphase(SEI)layer on the graphite surface.The SEI-implanted graphite electrode is made using a lithium bis(trifluoromethanesulfonyl)imide(LiTFSI)-based electrolyte and cycled with a lithium tetrafluoroborate LiBF4-based electrolyte.This new electrode system shows significantly enhanced electrochemical properties owing to the rapid and efficient diffusion of Li ions through the SEI layer between the electrolyte and electrode.This graphite electrode with its pre-formed SEI layer achieves a reversible capacity of 357 mAh g^-1 at 0.5 C after 50 cycles,which is significantly higher than that of commercial lithium-ion battery systems constructed with LiPF6(312mAh g^-1).The resulting unique electrode system could present a new avenue in SEI research for highperformance lithium-ion batteries.
基金supported by the National Natural Science Foundation of China (21905033, 52271201)the Science and Technology Department of Sichuan Province (2022YFG0100,2022ZYD0045)。
文摘Promoting inorganic-rich solid-electrolyte interphase (SEI) formation by constructing anion-rich solvated structures is a promising strategy for improving the long-term cycling of lithium-metal batteries.However,the increase of anions within the solvated structure inevitably reduces the coordination of Li^(+) with the solvent,which leads to a low lithium diffusion coefficient and a decreased lithium conductivity.Here,high entropy electrolyte is achieved by increasing the molecular diversity in electrolyte.Multiple anions (TFSI^(-),FSI^(-),NO_(3)^(-) and PF_(6)^(-)) presented in entropy electrolyte individually coordinate with Li^(+),creating a diverse and anion-rich solvation structure.The large variety of solvation structures leads to a diversified Li^(+) diffusion barriers in the electrolyte,which results in the increase of channels available for Li^(+) diffusion.Thus,three-dimensional diffusion with high Li^(+) diffusion coefficient occurs in HE electrolytes.Furthermore,the anion-rich solvation structures promote the formation of the inorganic-rich SEI.As a result,over 2000 h of reversible Li plating/stripping with a low overpotential less than 27 mV is achieved in Li||Li cell using electrolyte modified by high-entropy strategy.Besides,the Li||LFP full cell with a negative capacity/positive capacity (N/P) ratio of 4.52 exhibits remarkably enhanced cycling stability,retaining 83.6% of its initial capacity after 150 cycles.This strategy offers a novel approach for accelerating Li^(+) transport kinetics and constructing stable SEI in lithium metal batteries.
基金supported by the National Natural Science Foundation of China(Grant No.50572127)
文摘It is necessary to pay more attention to the durability of concrete undergoing freeze-thaw cycles and seawater attack simultaneously.Investigated are the effects of water-binder ratio,fly ash（FA）contents and air-entraining agent on resistance to frost and chloride diffusion of marine concrete blended with FA in natural seawater.The results show that fly ash does not improve the frost resistance of concrete but can improve its resistance to chloride diffusion by addition of less than 30%.The resistance to frost and chloride diffusion of FA concrete can be improved with the decrease of water-binder ratio,and FA may improve both of them simultaneously only being mixed with air-entraining agent.A ratio（named as R）of the frost-resisting durability factor to chloride diffusion coefficient can be used to evaluate the durability of marine concrete.Scanning electron microscope（SEM）analyses are consistent with the evaluations by the value of R.
文摘Recycled large aggregate self-compacting concrete (RLA-SCC) within multiple weak areas. These weak areas have poor resistance to chloride ion erosion, which affects the service life of RLA-SCC in the marine environment. A three-dimensional multi-phase mesoscopic numerical model of RLA-SCC was established to simulate the chloride ions transportation in concrete. Experiments of RLA-SCC immersing in chloride solution were carried out to verify the simulation results. The effects of recycled large aggregate (RLA) content and RLA particle size on the service life of concrete were explored. The results indicate that the mesoscopic numerical simulation results are in good agreement with the experimental results. At the same depth, the closer to the surface of the RLA, the greater the chloride ion concentration. The service life of RLA-SCC in marine environment decreases with the increase of RLA content. Compared with the service life of 20% content, the service life of 25% and 30% content decreased by 20% and 42% respectively. Increasing the particle size of RLA can effectively improve the service life of RLA-SCC in chloride environment. Compared with the service life of 50 mm particle size, the service life of 70 mm and 90 mm increased by 61% and 163%, respectively. .
基金supported by the National Major Scientific Equipment R&D Project (No. ZDYZ2010-2)the National Natural Science Foundation of China (No. 51307165)
文摘In situ NMR measurements of the diffusion coefficients,including an estimate of signal strength,of lithium ion conductor using diffusion-weighting pulse sequence are performed in this study.A cascade bilinear model is proposed to estimate the diffusion sensitivity factors of pulsed-field gradient using prior information of the electrochemical performance and Arrhenius constraint.The model postulates that the active lithium nuclei participating electrochemical reaction are relevant to the NMR signal intensity,when discharge rate or temperature condition is varying.The electrochemical data and the NMR signal strength show a highly fit with the proposed model according our simulation and experiments.Furthermore,the diffusion time is constrained by temperature based on Arrhenius equation of reaction rates dependence.An experimental calculation of Li_4Ti_5O_（12）（LTO）/carbon nanotubes（CNTs） with the electrolyte evaluating at 20 ℃ is presented,which the b factor is estimated by the discharge rate.
基金supported by the National Natural Science Foundation of China (21938005 and 21776197)Key Laboratory of Coal Science and Technology, Education Ministry and Shanxi Province, Taiyuan University of Technology
文摘Sodium(Na)metal batteries with a high volumetric energy density that can be operated at high rates are highly desirable.However,an uneven Na-ion migration in bulk Na anodes leads to localized deposition/dissolution of sodium during high-rate plating/stripping behaviors,followed by severe dendrite growth and loose stacking.Herein,we engineer the Na hybrid anode with sodiophilic Na_(3)Bi-penetration to develop the abundant phase-boundary ionic transport channels.Compared to intrinsic Na,the reduced adsorption energy and ion-diffusion barrier on Na_(3)Bi ensure even Na^(+)nucleation and rapid Na^(+)migration within the hybrid electrode,leading to uniform deposition and dissolution at high current densities.Furthermore,the bismuthide enables compact Na deposition within the sodiophilic framework during cycling,thus favoring a high volumetric capacity.Consequently,the obtained anode was endowed with a high current density(up to 5 mA∙cm^(−2)),high areal capacity(up to 5 mA∙h∙cm^(−2)),and long-term cycling stability(up to 2800 h at 2 mA∙cm^(−2)).
基金supported by the National Natural Science Foundation of China (NSFC 21103184)the Ph.D.Programs Foundation (20100041110017) of Ministry of Education of Chinathe Fundamental Research Funds for the Central Universities
文摘Mesoporous LiFePO4/C composites containing 80 wt% of highly dispersed LiFePO4 nanoparticles(4-6 nm) were fabricated using bimodal mesoporous carbon(BMC) as continuous conductive networks. The unique pore structure of BMC not only promises good particle connectivity for LiFePO4, but also acts as a rigid nano-confinement support that controls the particle size. Furthermore, the capacities were investigated respectively based on the weight of LiFePO4 and the whole composite. When calculated based on the weight of the whole composite, it is 120 mAh·g-1at 0.1 C of the high loading electrode and 42 mAh·g-1at 10 C of the low loading electrode. The electrochemical performance shows that high LiFePO4 loading benefits large tap density and contributes to the energy storage at low rates, while the electrode with low content of LiFePO4 displays superior high rate performance, which can mainly be due to the small particle size, good dispersion and high utilization of the active material, thus leading to a fast ion and electron diffusion.
