The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed tha...The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.展开更多
Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems.Metal-organic frameworks(MOFs),as a new type of porous material,show the advantages o...Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems.Metal-organic frameworks(MOFs),as a new type of porous material,show the advantages of large specific surface area,high porosity,low density,and adjustable pore size,exhibiting a broad application prospect in the field of electrocatalytic reactions,batteries,particularly in the field of supercapacitors.This comprehensive review outlines the recent progress in synthetic methods and electrochemical performances of MOF materials,as well as their applications in supercapacitors.Additionally,the superiorities of MOFs-related materials are highlighted,while major challenges or opportunities for future research on them for electrochemical supercapacitors have been discussed and displayed,along with extensive experimental experiences.展开更多
The application of Sb_(2)S_(3)with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency(ICE).In this work,natural ...The application of Sb_(2)S_(3)with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency(ICE).In this work,natural stibnite modified by carbon dots(Sb_(2)S_(3)@xCDs)is elaborately designed with high ICE.Greatly,chemical processes of local oxidation–partial reduction–deep coupling for stibnite reduction of CDs are clearly demonstrated,confirmed with in situ high-temperature X-ray diffraction.More impressively,the ICE for lithium-ion batteries(LIBs)is enhanced to 85%,through the effect of oxygen-rich carbon matrix on C–S bonds which inhibit the conversion of sulfur to sulfite,well supported by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations.Not than less,it is found that Sb–O–C bonds existed in the interface effectively promote the electronic conductivity and expedite ion transmission by reducing the bandgap and restraining the slip of the dislocation.As a result,the optimal sample delivers a tremendous reversible capacity of 660 mAh g^(−1)in LIBs at a high current rate of 5 A g^(−1).This work provides a new methodology for enhancing the electrochemical energy storage performance of metal sulfides,especially for improving the ICE.展开更多
Carbonaceous materials have been regarded as highly promising anode candidates for potassium storage with their cost-effectiveness and environmental benignity.However,low specific capacity and difficulty in large-scal...Carbonaceous materials have been regarded as highly promising anode candidates for potassium storage with their cost-effectiveness and environmental benignity.However,low specific capacity and difficulty in large-scale synthesis largely hinder their further development.Herein,a thermal-induced potassium–carbon alloy phase(K_(x)C_(y))with the expanded interlayer spacing strategy is first put forward.Through in situ high-temperature X-ray diffraction,a K_(2)C_(2) phase is evoked by thermal energy during the in-situ carbonization process of carbon quantum dots intermediate derived from potassium-containing precursors,whereas no lithium or sodium–carbon alloy phase is observed from lithium/sodium-containing precursors.The asobtained ultra-thin carbon nanosheets achieve adjustable layer spacing,preparation in bulk,delivering reversible potassium storage of 403.4 mAh g^(−1) at 100 mA g^(−1) and 161.2 mAh g^(−1) even at 5.0 A g^(−1),which is one of the most impressive K-storage performances reported so far with great potential application.Furthermore,the assembled potassium-ion hybrid capacitor by combining the impressive CFMs-900 anode with the three-dimensional framework-activated carbon delivers a high energy-power density of 251.7 Wh kg^(−1) at 250Wkg^(−1) with long-term stability.This study opens a scalable avenue to realize the expanded interlayer spacing,which can be extended to other multicarboxyl potassium salts and can provide approach for the design of high-performance carbon anode materials for potassium storage.展开更多
P2-type Mn-based layered oxides are viewed as promising cathode materials for sodium ion battery by virtue of their high theoretical capacity.Considering that pure Na_(2/3)MnO_(2)suffers from poor cycling performances...P2-type Mn-based layered oxides are viewed as promising cathode materials for sodium ion battery by virtue of their high theoretical capacity.Considering that pure Na_(2/3)MnO_(2)suffers from poor cycling performances,Cu-substitution strategy is proposed to effectively alleviate this issue.However,the structural evolution mechanism of the Cu-containing samples still remains unclear.Herein,we propose that CuSubstitution P2-type Na_(0.66)Mn_(1-x)Cu_(x)O_(2)with enlarged lattice parameters are conducive to improving the interlayer structure stability through mitigating TMO_(2)slabs distortion.Proved by synchrotron XAS spectra and ex/in situ XRD,the expansion/contraction of MnO_6 octahedron is dramatically reduced with the increased Cu content,showing the facilitated Na ion diffusion.Furthermore,when the ratio of Cu to Mn reaches 1:4,the phase transition from P2 to P'2 type at the end of discharge can be suppressed,resulting in the improved interlayer skeleton stability.The Cu-containing samples with stable interlayer structure exhibit high capacity retention and outstanding rate performances(a capacity of 79.9 m Ah g^(-1)at 5C).This Cu-substitution strategy provides a promising approach to designing highly stable cathodes.展开更多
Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources.However,the wholesale application of LiMn_(2)O_(4)is pr...Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources.However,the wholesale application of LiMn_(2)O_(4)is predominately plagued by its severe capacity degradation,mainly associated with the innate Jahn-Teller effect.Herein,single-crystalline LiMn_(2)O_(4)with Eu^(3+) doping is rationally designed to mitigate the detrimental Jahn-Teller distortion by tuning the chemical environment of MnO_(6) octahedra and accommodating localized electron,based on the unique aspheric flexible 4f electron orbit of rare-earth metal ions.Notably,the stretching of MnO_(6) octahedron stemmed from the Jahn-Teller effect in Eu-doped LiMn_(2)O_(4)is effectively suppressed,confirmed by theoretical calculation.Meanwhile,the structural stability of the material has been significantly enhanced due to the robust Mn–O band coherency and weakened phase transition,proved by synchrotron radiation absorption spectrum and operando X-ray diffraction.The corresponding active cathode manifests superior long-cycle stability after 300 loops at 2C and displays only a 0.011%capacity drop per cycle even at 5C.Given this,this modification tactic sheds new light on achieving superior long-cycle performances by suppressing distortion in various cathode materials.展开更多
Sacrificial pre-metallation strategy could compensate for the irreversible consumption of metal ions and reduce the potential of anode,thereby elevating the cycle performance as well as open-circuit voltage for full m...Sacrificial pre-metallation strategy could compensate for the irreversible consumption of metal ions and reduce the potential of anode,thereby elevating the cycle performance as well as open-circuit voltage for full metal ion capacitors(MICs).However,suffered from massive-dosage abuse,exorbitant decomposition potential,and side effects of decomposition residue,the wide application of sacrificial approach was restricted.Herein,assisted with density functional theory calculations,strongly coupled interface(M-O-C,M=Li/Na/K)and electron donating group have been put forward to regulate the band gap and highest occupied molecular orbital level of metal oxalate(M_(2)C_(2)O_(4)),reducing polarization phenomenon and Gibbs free energy required for decomposition,which eventually decrease the practical decomposition potential from 4.50 to 3.95 V.Remarkably,full sodium ion capacitors constituted of commercial materials(activated carbon//hard carbon)could deliver a prominent energy density of 118.2 Wh kg^(−1)as well as excellent cycle stability under an ultra-low dosage pre-sodiation reagent of 15-30 wt%(far less than currently 100 wt%).Noteworthily,decomposition mechanism of sacrificial compound and the relative influence on the system of MICs after pre-metallation were initially revealed by in situ differential electrochemical mass spectrometry,offering in-depth insights for comprehending the function of cathode additives.In addition,this breakthrough has been successfully utilized in high performance lithium/potassium ion capacitors with Li_(2)C_(2)O_(4)/K_(2)C_(2)O_(4) as pre-metallation reagent,which will convincingly promote the commercialization of MICs.展开更多
Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron an...Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron and Na~+conductivities,however,its real implementation is impeded by the grievous capacity decay and inferior rate capability.Herein,multivalent cation substituted microporous Na_(3.9)Fe_(2.9)Al_(0.1)(PO_(4))_(2)(P_(2)O_(7))(NFAPP)with wide operation-temperature is elaborately designed through regulating structure/interface coupled electron/ion transport.Greatly,the derived Na vacancy and charge rearrangement induced by trivalent Al^(3+)substitution lower the ions diffusion barriers,thereby endowing faster electron transport and Na^(+)mobility.More importantly,the existing Al-O-P bonds strengthen the local environment and alleviate the volume vibration during(de)sodiation,enabling highly reversible valence variation and structural evolution.As a result,remarkable cyclability(over 10,000 loops),ultrafast rate capability(200 C),and exceptional all-climate stability(-40-60℃)in half/full cells are demonstrated.Given this,the rational work might provide an actionable strategy to promote the electrochemical property of NFPP,thus unveiling the great application prospect of sodium iron mixed phosphate materials.展开更多
Although lithium-sulfur(Li-S)batteries with high specific energy exhibit great potential for next-generation energy-storage systems,their practical applications are limited by the growth of Li dendrites and lithium po...Although lithium-sulfur(Li-S)batteries with high specific energy exhibit great potential for next-generation energy-storage systems,their practical applications are limited by the growth of Li dendrites and lithium polysulfides(LiPSs)shuttling.Herein,a highly porous red phosphorus sponge(HPPS)with well distributed pore structure was efficiently prepared via a facile and largescale hydrothermal process for polysulfides adsorption and dendrite suppression.As experimental demonstrated,the porous red phosphorus modified separator with increased active site greatly promotes the chemisorption of LiPSs to efficiently immobilize the active sulfur within the cathode section,while Li metal anode activated by Li_(3)P interlayer with abundant ionically conductive channels significantly eliminates the barrier for uniform Li^(+)permeation across the interlayer,contributing to the enhanced stability for both S cathode and Li anode.Mediated by the HPPS,long-term stability of 1,200 h with minor voltage hysteresis is achieved in symmetric cells with Li_(3)P@Li electrode while Li-S half-cell based on HPPS modified separator delivers an outperformed reversibility of 783.0 mAh·g^(−1)after 300 cycles as well as high-rate performance of 694.5 mAh·g^(−1)at 3 C,which further boosts the HPPS tuned full cells in practical S loading(3 mg·cm^(−2))and thin Li3P@Li electrode(100μm)with a capacity retention of 71.8%after 200 cycles at 0.5 C.This work provides a cost-effective and metal free mediator for simultaneously alleviating the fundamental issues of both S cathode and Li anode towards high energy density and long cycle life Li-S full batteries.展开更多
The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quanti...The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quantity production largely hinder the further development.Herein,Cu_(5)FeS_(4-x)/C(CFS@C)heterojunction with rich sulfur vacancies has successfully achieved from natural bornite,presenting low costeffective and bulk-production prospect.Density functional theory(DFT)calculations indicate that rich vacancies in bulk phase can decrease band gap of bornite and thus improve its intrinsic electron conductivity,as well as the heterojunction spontaneously evokes a built-in electric field between its interfacial region,largely reducing the migration barrier from 1.27 e V to 0.75 e V.Benefited from these merits,the CFS@C electrodes deliver outperformed lithium storage performance,e.g.,high reversible capacity(822.4m Ah/g at 0.1 A/g),excellent cycling stability(up to 820 cycles at 2 A/g and 540 cycles at 5 A/g with respective capacity retention of over or nearly 100%).With CFS@C as anode and porous carbon nanosheets(PCS)as cathode,the assembled CFS@C//PCS LIC full cells exhibit high energy/power density characteristics of 139.2 Wh/kg at 2500 W/kg.This work is expected to offer significant insights into structure modifications/devising toward natural minerals for advanced energy-storage systems.展开更多
Sodium-ion batteries(SIBs) have gained more scientists’ interest, owing to some facts such as the natural abundance of Na, the similarities of physicochemical characteristics between Li and Na. The irreversible Na+io...Sodium-ion batteries(SIBs) have gained more scientists’ interest, owing to some facts such as the natural abundance of Na, the similarities of physicochemical characteristics between Li and Na. The irreversible Na+ions consumption during the first cycle of charge/discharge process(due to the formation of the solid electrolyte interface(SEI) on the electrode surface and other irreversible reactions) is the factor that determines high performance SIBs and largely reduces the capacity of the full cell SIBs. Thus, the initial coulombic efficiency(ICE) of SIBs for both anode and cathode materials, is a key parameter for high performance SIBs, and the point is to increase the transport rate of the Na+ions. Therefore, developing SIBs with high ICE and rate performance becomes vital to boost the commercialization of SIBs. Here we provide a review on the methods to improve the ICE and the rate performance, by summarizing some methods of improving the ICE and rate performance of the anode and cathode materials for SIBs, and end by a conclusion with some perspectives and recommendations.展开更多
The rapid growth in global electric vehicles(EVs)sales has promoted the development of Co-free,Ni-rich layered cathodes for state-of-the-art high energy-density,inexpensive lithium-ion batteries(LIBs).However,progress...The rapid growth in global electric vehicles(EVs)sales has promoted the development of Co-free,Ni-rich layered cathodes for state-of-the-art high energy-density,inexpensive lithium-ion batteries(LIBs).However,progress in their commercial use has been seriously hampered by exasperating performance deterioration and safety concerns.Herein,a robust single-crystalline,Co-free,Ni-rich LiNi_(0.95)Mn_(0.05)O_(2)(SC-NM95)cathode is successfully designed using a molten salt-assisted method,and it exhibits better structural stability and cycling durability than those of polycrystalline LiNi_(0.95)Mn_(0.05)O_(2) (PC-NM95).Notably,the SC-NM95 cathode achieves a high discharge capacity of 218.2 mAh g^(-1),together with a high energy density of 837.3 Wh kg^(-1) at 0.1 C,mainly due to abundant Ni^(2+)/Ni^(3+) redox.It also presents an outstanding capacity retention(84.4%)after 200 cycles at 1 C,because its integrated single-crystalline structure effectively inhibits particle microcracking and surface phase transformation.In contrast,the PC-NM95 cathode suffers from rapid capacity fading owing to the nucleation and propagation of intergranular microcracking during cycling,facilitating aggravated parasitic reactions and rocksalt phase accumulation.This work provides a fundamental strategy for designing high-performance singlecrystalline,Co-free,Ni-rich cathode materials and also represents an important breakthrough in developing high-safe,low-cost,and high-energy LIBs.展开更多
Among the solid electrolytes for solid-state Li batteries,polymer electrolytes are actively explored on the basis of the good interfacial contact and easy making,while it is still constrained by slow ionic transport a...Among the solid electrolytes for solid-state Li batteries,polymer electrolytes are actively explored on the basis of the good interfacial contact and easy making,while it is still constrained by slow ionic transport and low lithium ion transference number.Herein,functional carbon dots-based Li+conductor(CD-Li)is designed to improve the dynamics and selectivity of Li+transport in polyethylene oxide(PEO)electrolyte.High ionic conductivity(1.0×10^(−4) S/cm,25℃)and Li+transference number(0.60)were successfully achieved within the CD‐Li‐based PEO composite electrolyte,which could be attributed to the enhanced chain movement and the limited motion of anion.Moreover,the characteristics of big volume of individual anions of CD-Li can provide more free Li^(+).As well,benefiting from the existence of F atom in the CD-Li,in-situ constructed LiF-containing interfacial layer is in favor of maintaining the interface stability and facilitating the rapid transmission of Li ions.The composite electrolyte with CD-Li can address the ionic conductivity issues accompanied with strengthening the interfacial stability.The distinctive composite electrolyte realizes the stable cycle performance for Li/LiFePO_(4) and Li/LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)batteries.The exploration of multifunctional carbon dot fillers provides new ideas for the efficient development of composite electrolytes.展开更多
基金National Natural Science Foundation of China(No.32260643)for financial support of this study。
文摘The physicochemical properties of plasma-activated water(PAW)generated under different process conditions were investigated,and their changes under different storage conditions were also studied.The results showed that increasing the processing time and power,and decreasing generated water volume,could cause an increase in the redox potential,conductivity,and temperature of PAW,and a decrease in its pH.A slower dissipation of the reactive oxygen and nitrogen species in PAW was found on storage at 4℃in a sealed conical flask than on storage at room temperature.The inactivation ability of plasma-activated lactic acid(LA)to Listeria monocytogenes(L.monocytogenes)and Pseudomonas aeruginosa(P.aeruginosa)was higher than that of PAW or LA alone under the same experimental conditions.The results of this study may provide theoretical information for the application of PAW as a potential antimicrobial agent in the future.
基金supported by the National Natural Science Foundation of China(52004338,51622406,21673298)Scientific Research Fund of Hunan Provincial Education Department(21B0017).
文摘Exploring new materials with high stability and capacity is full of challenges in sustainable energy conversion and storage systems.Metal-organic frameworks(MOFs),as a new type of porous material,show the advantages of large specific surface area,high porosity,low density,and adjustable pore size,exhibiting a broad application prospect in the field of electrocatalytic reactions,batteries,particularly in the field of supercapacitors.This comprehensive review outlines the recent progress in synthetic methods and electrochemical performances of MOF materials,as well as their applications in supercapacitors.Additionally,the superiorities of MOFs-related materials are highlighted,while major challenges or opportunities for future research on them for electrochemical supercapacitors have been discussed and displayed,along with extensive experimental experiences.
基金financially supported by the National Natural Science Foundation of China (51904342, 52074359, U21A20284)Hunan Provincial Science and Technology Plan (2020JJ3048)the Science and Technology Innovation Program of Hunan Province (2021RC3014, 2020RC4005, 2019RS1004)
文摘The application of Sb_(2)S_(3)with marvelous theoretical capacity for alkali metal-ion batteries is seriously limited by its poor electrical conductivity and low initial coulombic efficiency(ICE).In this work,natural stibnite modified by carbon dots(Sb_(2)S_(3)@xCDs)is elaborately designed with high ICE.Greatly,chemical processes of local oxidation–partial reduction–deep coupling for stibnite reduction of CDs are clearly demonstrated,confirmed with in situ high-temperature X-ray diffraction.More impressively,the ICE for lithium-ion batteries(LIBs)is enhanced to 85%,through the effect of oxygen-rich carbon matrix on C–S bonds which inhibit the conversion of sulfur to sulfite,well supported by X-ray photoelectron spectroscopy characterization of solid electrolyte interphase layers helped with density functional theory calculations.Not than less,it is found that Sb–O–C bonds existed in the interface effectively promote the electronic conductivity and expedite ion transmission by reducing the bandgap and restraining the slip of the dislocation.As a result,the optimal sample delivers a tremendous reversible capacity of 660 mAh g^(−1)in LIBs at a high current rate of 5 A g^(−1).This work provides a new methodology for enhancing the electrochemical energy storage performance of metal sulfides,especially for improving the ICE.
基金National Natural Science Foundation of China,Grant/Award Numbers:52004338,51904342,52074359Guangdong Provincial Department of Natural Resources,Grant/Award Number:2020-011Hunan Provincial Natural Science Foundation,Grant/Award Number:2020JJ5696。
文摘Carbonaceous materials have been regarded as highly promising anode candidates for potassium storage with their cost-effectiveness and environmental benignity.However,low specific capacity and difficulty in large-scale synthesis largely hinder their further development.Herein,a thermal-induced potassium–carbon alloy phase(K_(x)C_(y))with the expanded interlayer spacing strategy is first put forward.Through in situ high-temperature X-ray diffraction,a K_(2)C_(2) phase is evoked by thermal energy during the in-situ carbonization process of carbon quantum dots intermediate derived from potassium-containing precursors,whereas no lithium or sodium–carbon alloy phase is observed from lithium/sodium-containing precursors.The asobtained ultra-thin carbon nanosheets achieve adjustable layer spacing,preparation in bulk,delivering reversible potassium storage of 403.4 mAh g^(−1) at 100 mA g^(−1) and 161.2 mAh g^(−1) even at 5.0 A g^(−1),which is one of the most impressive K-storage performances reported so far with great potential application.Furthermore,the assembled potassium-ion hybrid capacitor by combining the impressive CFMs-900 anode with the three-dimensional framework-activated carbon delivers a high energy-power density of 251.7 Wh kg^(−1) at 250Wkg^(−1) with long-term stability.This study opens a scalable avenue to realize the expanded interlayer spacing,which can be extended to other multicarboxyl potassium salts and can provide approach for the design of high-performance carbon anode materials for potassium storage.
基金financially supported by the Science and Technology Foundation of Guizhou Province(QKHZC[2020]2Y037)the Science and Technology Innovation Program of Hunan Province(2020RC4005,2019RS1004)the Innovation Mover Program of Central South University(2020CX007)。
文摘P2-type Mn-based layered oxides are viewed as promising cathode materials for sodium ion battery by virtue of their high theoretical capacity.Considering that pure Na_(2/3)MnO_(2)suffers from poor cycling performances,Cu-substitution strategy is proposed to effectively alleviate this issue.However,the structural evolution mechanism of the Cu-containing samples still remains unclear.Herein,we propose that CuSubstitution P2-type Na_(0.66)Mn_(1-x)Cu_(x)O_(2)with enlarged lattice parameters are conducive to improving the interlayer structure stability through mitigating TMO_(2)slabs distortion.Proved by synchrotron XAS spectra and ex/in situ XRD,the expansion/contraction of MnO_6 octahedron is dramatically reduced with the increased Cu content,showing the facilitated Na ion diffusion.Furthermore,when the ratio of Cu to Mn reaches 1:4,the phase transition from P2 to P'2 type at the end of discharge can be suppressed,resulting in the improved interlayer skeleton stability.The Cu-containing samples with stable interlayer structure exhibit high capacity retention and outstanding rate performances(a capacity of 79.9 m Ah g^(-1)at 5C).This Cu-substitution strategy provides a promising approach to designing highly stable cathodes.
基金financially supported by the National Natural Science Foundation of China(U21A20284)the National Key Research and Development Program of China(2019YFC1907805)the Fundamental Research Funds for the Central Universities of Central South University(2021zzts0072)。
文摘Spinel LiMn_(2)O_(4)is recognized as one of the most competitive cathode candidates for lithium-ion batteries ascribed to environmentally benign and rich sources.However,the wholesale application of LiMn_(2)O_(4)is predominately plagued by its severe capacity degradation,mainly associated with the innate Jahn-Teller effect.Herein,single-crystalline LiMn_(2)O_(4)with Eu^(3+) doping is rationally designed to mitigate the detrimental Jahn-Teller distortion by tuning the chemical environment of MnO_(6) octahedra and accommodating localized electron,based on the unique aspheric flexible 4f electron orbit of rare-earth metal ions.Notably,the stretching of MnO_(6) octahedron stemmed from the Jahn-Teller effect in Eu-doped LiMn_(2)O_(4)is effectively suppressed,confirmed by theoretical calculation.Meanwhile,the structural stability of the material has been significantly enhanced due to the robust Mn–O band coherency and weakened phase transition,proved by synchrotron radiation absorption spectrum and operando X-ray diffraction.The corresponding active cathode manifests superior long-cycle stability after 300 loops at 2C and displays only a 0.011%capacity drop per cycle even at 5C.Given this,this modification tactic sheds new light on achieving superior long-cycle performances by suppressing distortion in various cathode materials.
基金supported by the National Natural Science Foundation of China(52004338)the Hunan Provincial Natural Science Foundation of China(2020JJ5696)+2 种基金the Science,and Technology Innovation Program of Hunan Province(2020RC4005,2019RS1004)Guangdong Provincial Department of Natural Resources(2020-011)supported in part by the High Performance Computing Center of Central South University.
文摘Sacrificial pre-metallation strategy could compensate for the irreversible consumption of metal ions and reduce the potential of anode,thereby elevating the cycle performance as well as open-circuit voltage for full metal ion capacitors(MICs).However,suffered from massive-dosage abuse,exorbitant decomposition potential,and side effects of decomposition residue,the wide application of sacrificial approach was restricted.Herein,assisted with density functional theory calculations,strongly coupled interface(M-O-C,M=Li/Na/K)and electron donating group have been put forward to regulate the band gap and highest occupied molecular orbital level of metal oxalate(M_(2)C_(2)O_(4)),reducing polarization phenomenon and Gibbs free energy required for decomposition,which eventually decrease the practical decomposition potential from 4.50 to 3.95 V.Remarkably,full sodium ion capacitors constituted of commercial materials(activated carbon//hard carbon)could deliver a prominent energy density of 118.2 Wh kg^(−1)as well as excellent cycle stability under an ultra-low dosage pre-sodiation reagent of 15-30 wt%(far less than currently 100 wt%).Noteworthily,decomposition mechanism of sacrificial compound and the relative influence on the system of MICs after pre-metallation were initially revealed by in situ differential electrochemical mass spectrometry,offering in-depth insights for comprehending the function of cathode additives.In addition,this breakthrough has been successfully utilized in high performance lithium/potassium ion capacitors with Li_(2)C_(2)O_(4)/K_(2)C_(2)O_(4) as pre-metallation reagent,which will convincingly promote the commercialization of MICs.
基金supported by the National Natural Science Foundation of China(52325405,52261135632,and U21A20284)the Science and Technology Foundation of Guizhou Province(QKHZC[2020]2Y037)+1 种基金the Fundamental Research Funds for the Central Universities of Central South University(2023XQLH070,2023XQLH069)the U19 station in the National Synchrotron Radiation Laboratory(NSRL)。
文摘Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))(NFPP)is currently drawing increased attention as a sodium-ion batteries(SIBs)cathode due to the cost-effective and NASICON-type structure features.Owing to the sluggish electron and Na~+conductivities,however,its real implementation is impeded by the grievous capacity decay and inferior rate capability.Herein,multivalent cation substituted microporous Na_(3.9)Fe_(2.9)Al_(0.1)(PO_(4))_(2)(P_(2)O_(7))(NFAPP)with wide operation-temperature is elaborately designed through regulating structure/interface coupled electron/ion transport.Greatly,the derived Na vacancy and charge rearrangement induced by trivalent Al^(3+)substitution lower the ions diffusion barriers,thereby endowing faster electron transport and Na^(+)mobility.More importantly,the existing Al-O-P bonds strengthen the local environment and alleviate the volume vibration during(de)sodiation,enabling highly reversible valence variation and structural evolution.As a result,remarkable cyclability(over 10,000 loops),ultrafast rate capability(200 C),and exceptional all-climate stability(-40-60℃)in half/full cells are demonstrated.Given this,the rational work might provide an actionable strategy to promote the electrochemical property of NFPP,thus unveiling the great application prospect of sodium iron mixed phosphate materials.
基金supported by the National Natural Science Foundation of China(Nos.52074359,51904342,and U21A20284)the Hunan Provincial Science and Technology Plan(No.2020JJ3048)the Science and Technology Innovation Program of Hunan Province(Nos.2021RC3014,2020RC4005,and 2019RS1004).
文摘Although lithium-sulfur(Li-S)batteries with high specific energy exhibit great potential for next-generation energy-storage systems,their practical applications are limited by the growth of Li dendrites and lithium polysulfides(LiPSs)shuttling.Herein,a highly porous red phosphorus sponge(HPPS)with well distributed pore structure was efficiently prepared via a facile and largescale hydrothermal process for polysulfides adsorption and dendrite suppression.As experimental demonstrated,the porous red phosphorus modified separator with increased active site greatly promotes the chemisorption of LiPSs to efficiently immobilize the active sulfur within the cathode section,while Li metal anode activated by Li_(3)P interlayer with abundant ionically conductive channels significantly eliminates the barrier for uniform Li^(+)permeation across the interlayer,contributing to the enhanced stability for both S cathode and Li anode.Mediated by the HPPS,long-term stability of 1,200 h with minor voltage hysteresis is achieved in symmetric cells with Li_(3)P@Li electrode while Li-S half-cell based on HPPS modified separator delivers an outperformed reversibility of 783.0 mAh·g^(−1)after 300 cycles as well as high-rate performance of 694.5 mAh·g^(−1)at 3 C,which further boosts the HPPS tuned full cells in practical S loading(3 mg·cm^(−2))and thin Li3P@Li electrode(100μm)with a capacity retention of 71.8%after 200 cycles at 0.5 C.This work provides a cost-effective and metal free mediator for simultaneously alleviating the fundamental issues of both S cathode and Li anode towards high energy density and long cycle life Li-S full batteries.
基金supported by the National Natural Science Foundation of China(Nos.52004338,22378431)Hunan Provincial Natural Science Foundation(Nos.2022JJ20075,2023JJ40210)+1 种基金Scientific Research Fund of Hunan Provincial Education Department(No.21B0017)Central South University Innovation-Driven Research Programme(No.2023CXQD008)。
文摘The exploration of advanced materials through rational structure/phase design is the key to develop highperformance lithium-ion capacitors(LICs).However,high complexity of material preparation and difficulty in quantity production largely hinder the further development.Herein,Cu_(5)FeS_(4-x)/C(CFS@C)heterojunction with rich sulfur vacancies has successfully achieved from natural bornite,presenting low costeffective and bulk-production prospect.Density functional theory(DFT)calculations indicate that rich vacancies in bulk phase can decrease band gap of bornite and thus improve its intrinsic electron conductivity,as well as the heterojunction spontaneously evokes a built-in electric field between its interfacial region,largely reducing the migration barrier from 1.27 e V to 0.75 e V.Benefited from these merits,the CFS@C electrodes deliver outperformed lithium storage performance,e.g.,high reversible capacity(822.4m Ah/g at 0.1 A/g),excellent cycling stability(up to 820 cycles at 2 A/g and 540 cycles at 5 A/g with respective capacity retention of over or nearly 100%).With CFS@C as anode and porous carbon nanosheets(PCS)as cathode,the assembled CFS@C//PCS LIC full cells exhibit high energy/power density characteristics of 139.2 Wh/kg at 2500 W/kg.This work is expected to offer significant insights into structure modifications/devising toward natural minerals for advanced energy-storage systems.
基金financially supported by National Key Research and Development Program of China (No.2019YFC1907805)National Natural Science Foundation of China (No.52004338)+1 种基金Hunan Provincial Natural Science Foundation of China (No.2020JJ5696)Guangdong Provincial Department of Natural Resources (No.2020-011)。
文摘Sodium-ion batteries(SIBs) have gained more scientists’ interest, owing to some facts such as the natural abundance of Na, the similarities of physicochemical characteristics between Li and Na. The irreversible Na+ions consumption during the first cycle of charge/discharge process(due to the formation of the solid electrolyte interface(SEI) on the electrode surface and other irreversible reactions) is the factor that determines high performance SIBs and largely reduces the capacity of the full cell SIBs. Thus, the initial coulombic efficiency(ICE) of SIBs for both anode and cathode materials, is a key parameter for high performance SIBs, and the point is to increase the transport rate of the Na+ions. Therefore, developing SIBs with high ICE and rate performance becomes vital to boost the commercialization of SIBs. Here we provide a review on the methods to improve the ICE and the rate performance, by summarizing some methods of improving the ICE and rate performance of the anode and cathode materials for SIBs, and end by a conclusion with some perspectives and recommendations.
基金This work was financially supported by National Key Research and Development Program of China(2019YFC1907805)Fundamental Research Funds for the Central Universities of Central South University(2021zzts0072).
文摘The rapid growth in global electric vehicles(EVs)sales has promoted the development of Co-free,Ni-rich layered cathodes for state-of-the-art high energy-density,inexpensive lithium-ion batteries(LIBs).However,progress in their commercial use has been seriously hampered by exasperating performance deterioration and safety concerns.Herein,a robust single-crystalline,Co-free,Ni-rich LiNi_(0.95)Mn_(0.05)O_(2)(SC-NM95)cathode is successfully designed using a molten salt-assisted method,and it exhibits better structural stability and cycling durability than those of polycrystalline LiNi_(0.95)Mn_(0.05)O_(2) (PC-NM95).Notably,the SC-NM95 cathode achieves a high discharge capacity of 218.2 mAh g^(-1),together with a high energy density of 837.3 Wh kg^(-1) at 0.1 C,mainly due to abundant Ni^(2+)/Ni^(3+) redox.It also presents an outstanding capacity retention(84.4%)after 200 cycles at 1 C,because its integrated single-crystalline structure effectively inhibits particle microcracking and surface phase transformation.In contrast,the PC-NM95 cathode suffers from rapid capacity fading owing to the nucleation and propagation of intergranular microcracking during cycling,facilitating aggravated parasitic reactions and rocksalt phase accumulation.This work provides a fundamental strategy for designing high-performance singlecrystalline,Co-free,Ni-rich cathode materials and also represents an important breakthrough in developing high-safe,low-cost,and high-energy LIBs.
基金supported by the Science and Technology Innovation Program of Hunan Province(Nos.2021RC3014,2020RC4005,2019RS1004)the National Natural Science Foundation of China(Nos.U21A20284,52074359,51904342)+1 种基金Hunan Provincial Science and Technology Plan(No.2020JJ3048)Innovation Mover Program of Central South University(No.2020CX007).
文摘Among the solid electrolytes for solid-state Li batteries,polymer electrolytes are actively explored on the basis of the good interfacial contact and easy making,while it is still constrained by slow ionic transport and low lithium ion transference number.Herein,functional carbon dots-based Li+conductor(CD-Li)is designed to improve the dynamics and selectivity of Li+transport in polyethylene oxide(PEO)electrolyte.High ionic conductivity(1.0×10^(−4) S/cm,25℃)and Li+transference number(0.60)were successfully achieved within the CD‐Li‐based PEO composite electrolyte,which could be attributed to the enhanced chain movement and the limited motion of anion.Moreover,the characteristics of big volume of individual anions of CD-Li can provide more free Li^(+).As well,benefiting from the existence of F atom in the CD-Li,in-situ constructed LiF-containing interfacial layer is in favor of maintaining the interface stability and facilitating the rapid transmission of Li ions.The composite electrolyte with CD-Li can address the ionic conductivity issues accompanied with strengthening the interfacial stability.The distinctive composite electrolyte realizes the stable cycle performance for Li/LiFePO_(4) and Li/LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)batteries.The exploration of multifunctional carbon dot fillers provides new ideas for the efficient development of composite electrolytes.
基金supported by the National Natural Science Foundation of China(U21A20284)Science and Technology Foundation of Guizhou Province(QKHZC20202Y037)+4 种基金the Science and Technology Innovation Program of Hunan Province(2020RC40052019RS1004)Innovation Mover Program of Central South University(2020CX007)National Research Foundation of Korea(NRF-2017R1A2B3004383)the China Scholarship Council(CSC)for the financial support(202006370306)。