Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical window.E...Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical window.EC is also the most widely used electrolyte solvent in sodium ion batteries.However,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell failure.To address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based electrolytes.Specifically,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na batteries.The batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.展开更多
Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinet...Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability.展开更多
(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算...(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。展开更多
Zn(CF_(3)SO_(3))_(2)as an electrolyte has been widely used to improve the electrochemical performance for ZIBs due to that the bulky CF_(3)SO_(3)-can reduce the solvation effect of Zn^(2+)and promote the ionic diffusi...Zn(CF_(3)SO_(3))_(2)as an electrolyte has been widely used to improve the electrochemical performance for ZIBs due to that the bulky CF_(3)SO_(3)-can reduce the solvation effect of Zn^(2+)and promote the ionic diffusion.Herein,we found that Zn(CF_(3)SO_(3))_(2)electrolyte can induce different electrochemical mechanisms from ZnSO_(4)electrolyte.Compared to the ZnSO^(4)electrolyte,the HNaV_(6)O_(16)·4H2_(O)electrode with Zn(CF_(3)SO_(3))_(2)electrolyte exhibits a high capacity of 444 mAh·g^(-1)at 500 mA·g^(-1)with a capacity retention of 92.3%after 80 cycles.Even,at a high rate of 5 Ag-1,the HNaV_(6)O_(16)·4H_(2)O electrode delivers an initial discharge capacity of 328 mAh·g^(-1)with a capacity retention of 93.7%after 1000 cycles.Differing from the mechanism with ZnSO4 electrolyte,the excellent cycle stability of HNaV_(6)O_(16)·4H_(2)Oelectrode can be attributed to the in-situ phase transformation to ZnxV_(2)O_(5)·nH_(2)O based on the co-intercalation of Zn^(2+)/H^(+).展开更多
While aqueous Zn-Na hybrid batteries have garnered widespread attention because of their low cost and high safety,it is still challenging to achieve long cycle-life and stable discharge-voltage due to sluggish reactio...While aqueous Zn-Na hybrid batteries have garnered widespread attention because of their low cost and high safety,it is still challenging to achieve long cycle-life and stable discharge-voltage due to sluggish reaction kinetics,zinc dendrite formation,and side reactions.Herein,we design a Zn^(2+)/Na^(+) dual-salt battery,in which sodiation of the NVP cathode favors zinc intercalation under an energy threshold,leading to decoupled redox reactions on the cathode and anode.Systematic investigations of the electrolyte effects show that the ion intercalation mechanism and the kinetics in the mixture of triflate-and acetate-based electrolytes are superior to those in the common acetate-only electrolytes.As a result,we have achieved fast discharging capability,suppressed zinc dendrites,a stable discharge voltage at 1.45 V with small polarization,and nearly 100%Coulombic efficiency in the dual-salt mixture electrolyte with optimized concentration of 1 M Zn(OAc)_(2)+1 M NaCF_(3)SO_(3).This work demonstrates the importance of electrolyte regulation in aqueous dual-salt hybrid batteries for the energy storage.展开更多
Although aqueous zinc-ion batteries have gained great development due to their many merits,the frozen aqueous electrolyte hinders their practical application at low temperature conditions.Here,the synergistic e ect of...Although aqueous zinc-ion batteries have gained great development due to their many merits,the frozen aqueous electrolyte hinders their practical application at low temperature conditions.Here,the synergistic e ect of cation and anion to break the hydrogen-bonds network of original water molecules is demonstrated by multi-perspective characterization.Then,an aqueous-salt hydrates deep eutectic solvent of 3.5 M Mg(ClO_(4))_(2)+1 M Zn(ClO_(4))_(2)is proposed and displays an ultralow freezing point of-121℃.A high ionic conductivity of 1.41 mS cm-1 and low viscosity of 22.9 mPa s at-70℃ imply a fast ions transport behavior of this electrolyte.With the benefits of the low-temperature electrolyte,the fabricated Zn||Pyrene-4,5,9,10-tetraone(PTO)and Zn||Phenazine(PNZ)batteries exhibit satisfactory low-temperature performance.For example,Zn||PTO battery shows a high discharge capacity of 101.5 mAh g^(-1)at 0.5 C(200 mA g^(-1))and 71 mAh g^(-1)at 3C(1.2 A g^(-1))when the temperature drops to-70℃.This work provides an unique view to design anti-freezing aqueous electrolyte.展开更多
开发高性能正极材料是限制锌离子电池发展的重要因素.Na_(3)V_(2)(PO_(4))_(3)(NVP)是一种典型NASICON结构的材料,其作为锌离子电池正极材料具有较高的工作电压,然而其循环性能较差,通常仅200圈.本文首次系统地研究了该材料储锌性能的...开发高性能正极材料是限制锌离子电池发展的重要因素.Na_(3)V_(2)(PO_(4))_(3)(NVP)是一种典型NASICON结构的材料,其作为锌离子电池正极材料具有较高的工作电压,然而其循环性能较差,通常仅200圈.本文首次系统地研究了该材料储锌性能的衰退机理.研究表明,在水系电解液中NVP的自发溶解及首圈放电过程中材料的不可逆相变是其容量衰退的主要原因.采用含锌有机电解液虽可避免其溶解,但锌离子的嵌入易导致晶体结构的坍塌.本文首次引入钠离子作为新的载流子并构建有机Na/Zn混合离子电解液.其中,两种金属离子在NVP中高度可逆的共插层反应助力Zn/Na_(3)V_(2)-(PO_(4))_(3)电池实现了84 mA h g^(−1)的较高容量以及在大电流密度下循环600圈容量零衰减的高稳定性.展开更多
Flexible power sources featuring high-performance,prominent flexibility and raised safety have received mounting attention in the area of wearable electronic devices.However,many great challenges remain to be overcome...Flexible power sources featuring high-performance,prominent flexibility and raised safety have received mounting attention in the area of wearable electronic devices.However,many great challenges remain to be overcome,notably the design and fabrication of flexible electrodes with excellent electrochemical performance and matching them with safe and reliable electrolytes.Herein,a facile approach for preparing flexible electrodes,which employs carbon cloth derived from commercial cotton cloth as the substrate of cathode and a flexible anode,is proposed and investigated.The promising cathode(NVPOF@FCC)with high conductivity and outstanding flexibility is prepared by efficiently coating Na_(3)V_(2)(PO_(4))_(2)O_(2)F(NVPOF)on flexible carbon cloth(FCC),which exhibits remarkable electrochemical performance and the significantly improved reaction kinetics.More importantly,a novel flexible quasi-solid-state sodium-ion full battery(QSFB)is feasibly assembled by sandwiching a P(VDF-HFP)-NaClO_(4) gel-polymer electrolyte film between the advanced NVPOF@FCC cathode and FCC anode.And the QSFBs are further evaluated in flexible pouch cells,which not only demonstrates excellent energy-storage performance in aspect of great cycling stability and high-rate capability,but also impressive flexibility and safety.This work offers a feasible and effective strategy for the design of flexible electrodes,paving the way for the progression of practical and sustainable flexible batteries.展开更多
基金supported by the National Natural Science Foundation of China(52172201,51732005,51902118,and 52102249)the China Postdoctoral Science Foundation(2019M662609and 2020T130217)for financial support。
文摘Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical window.EC is also the most widely used electrolyte solvent in sodium ion batteries.However,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell failure.To address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based electrolytes.Specifically,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na batteries.The batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.
基金supported by the funding from the National Natural Science Foundation of China(grant nos.51902187,52072224,and 51732007)the Natural Science Foundation of Shandong Province(ZR2018BEM010)+3 种基金the Science Fund for Distinguished Young Scholars of Shandong Province(ZR2019JQ16)the Fundamental Research Funds of Shandong UniversityYoung Elite Scientist Sponsorship Program by CAST(YESS)the support from Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong
文摘Driven by safety issues,environmental concerns,and high costs,rechargeable aqueous zinc-ion batteries(ZIBs)have received increasing attention in recent years owing to their unique advantages.However,the sluggish kinetics of divalent charge Zn^(2+)in the cathode materials caused by the strong electrostatic interaction and their unsatisfactory cycle life hinder the development of ZIBs.Herein,organic cations and Zn^(2+)ions co-pre-inserted vanadium oxide([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O are reported as the cathode for ultra-stable aqueous ZIBs,in which the weaker electrostatic interactions between Zn^(2+)and organic ion-pinned vanadium oxide can induce the high reversibility of Zn^(2+)insertion and extraction,thereby improving the cycle life.It is demonstrated that([N(CH_(3))_(4)]_(0.77),Zn_(0.23))V_(8)O_(20)·3.8H_(2)O cathodes deliver a discharge capacity of 181 mA h g^(-1)at8 A g^(-1)and ultra-long life span(99.5%capacity retention after 2000 cycles).A reversible Zn^(2+)/H^(+)ions(de)intercalation storage process and pseudocapacitive charge storage are characterized.The weaker interactions between organic ion and Zn^(2+)open a novel avenue for the design of highly reversible cathode materials with long-term cycling stability.
文摘(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。
基金This study was financially supported by the National Natural Science Foundation of China(No.51772193)China Postdoctral Science Foundation(No.2019T250254).
文摘Zn(CF_(3)SO_(3))_(2)as an electrolyte has been widely used to improve the electrochemical performance for ZIBs due to that the bulky CF_(3)SO_(3)-can reduce the solvation effect of Zn^(2+)and promote the ionic diffusion.Herein,we found that Zn(CF_(3)SO_(3))_(2)electrolyte can induce different electrochemical mechanisms from ZnSO_(4)electrolyte.Compared to the ZnSO^(4)electrolyte,the HNaV_(6)O_(16)·4H2_(O)electrode with Zn(CF_(3)SO_(3))_(2)electrolyte exhibits a high capacity of 444 mAh·g^(-1)at 500 mA·g^(-1)with a capacity retention of 92.3%after 80 cycles.Even,at a high rate of 5 Ag-1,the HNaV_(6)O_(16)·4H_(2)O electrode delivers an initial discharge capacity of 328 mAh·g^(-1)with a capacity retention of 93.7%after 1000 cycles.Differing from the mechanism with ZnSO4 electrolyte,the excellent cycle stability of HNaV_(6)O_(16)·4H_(2)Oelectrode can be attributed to the in-situ phase transformation to ZnxV_(2)O_(5)·nH_(2)O based on the co-intercalation of Zn^(2+)/H^(+).
基金financially supported by the Hightech Research Key laboratory of Zhenjiang(SS2018002)Jiangsu Postdoctoral Research Funding Program(2020Z257)+3 种基金support from MOE Tier 1 grant(RG 157/19)from the China-Singapore International Joint Research Institute(204-A018002)financial support from the Guangdong Natural Science Funds(2019A1515010675)the Science and Technology Project of Shenzhen(JCYJ20210324094206019,KQJSCX20180328094001794)。
文摘While aqueous Zn-Na hybrid batteries have garnered widespread attention because of their low cost and high safety,it is still challenging to achieve long cycle-life and stable discharge-voltage due to sluggish reaction kinetics,zinc dendrite formation,and side reactions.Herein,we design a Zn^(2+)/Na^(+) dual-salt battery,in which sodiation of the NVP cathode favors zinc intercalation under an energy threshold,leading to decoupled redox reactions on the cathode and anode.Systematic investigations of the electrolyte effects show that the ion intercalation mechanism and the kinetics in the mixture of triflate-and acetate-based electrolytes are superior to those in the common acetate-only electrolytes.As a result,we have achieved fast discharging capability,suppressed zinc dendrites,a stable discharge voltage at 1.45 V with small polarization,and nearly 100%Coulombic efficiency in the dual-salt mixture electrolyte with optimized concentration of 1 M Zn(OAc)_(2)+1 M NaCF_(3)SO_(3).This work demonstrates the importance of electrolyte regulation in aqueous dual-salt hybrid batteries for the energy storage.
基金supported the National Natural Science Foundation of China(51771094 and 21835004)Ministry of Education of China(B12015)Tianjin Natural Science Foundation(18JCZDJC31500)。
文摘Although aqueous zinc-ion batteries have gained great development due to their many merits,the frozen aqueous electrolyte hinders their practical application at low temperature conditions.Here,the synergistic e ect of cation and anion to break the hydrogen-bonds network of original water molecules is demonstrated by multi-perspective characterization.Then,an aqueous-salt hydrates deep eutectic solvent of 3.5 M Mg(ClO_(4))_(2)+1 M Zn(ClO_(4))_(2)is proposed and displays an ultralow freezing point of-121℃.A high ionic conductivity of 1.41 mS cm-1 and low viscosity of 22.9 mPa s at-70℃ imply a fast ions transport behavior of this electrolyte.With the benefits of the low-temperature electrolyte,the fabricated Zn||Pyrene-4,5,9,10-tetraone(PTO)and Zn||Phenazine(PNZ)batteries exhibit satisfactory low-temperature performance.For example,Zn||PTO battery shows a high discharge capacity of 101.5 mAh g^(-1)at 0.5 C(200 mA g^(-1))and 71 mAh g^(-1)at 3C(1.2 A g^(-1))when the temperature drops to-70℃.This work provides an unique view to design anti-freezing aqueous electrolyte.
基金This work was supported by the National Natural Science Foundation of China(91963210,U1801255,and 51872340)the Fundamental Research Funds for the Central Universities,China(18lgpy06).
文摘开发高性能正极材料是限制锌离子电池发展的重要因素.Na_(3)V_(2)(PO_(4))_(3)(NVP)是一种典型NASICON结构的材料,其作为锌离子电池正极材料具有较高的工作电压,然而其循环性能较差,通常仅200圈.本文首次系统地研究了该材料储锌性能的衰退机理.研究表明,在水系电解液中NVP的自发溶解及首圈放电过程中材料的不可逆相变是其容量衰退的主要原因.采用含锌有机电解液虽可避免其溶解,但锌离子的嵌入易导致晶体结构的坍塌.本文首次引入钠离子作为新的载流子并构建有机Na/Zn混合离子电解液.其中,两种金属离子在NVP中高度可逆的共插层反应助力Zn/Na_(3)V_(2)-(PO_(4))_(3)电池实现了84 mA h g^(−1)的较高容量以及在大电流密度下循环600圈容量零衰减的高稳定性.
基金supported by the National Natural Science Foundation of China(No.91963118)Science Technology Program of Jilin Province(No.20200201066JC)+2 种基金Fundamental Research Funds for the Central Universities(No.2412020QD013)China Postdoctoral Science Foundation(No.2019M661187)the National Postdoctoral Program for Innovative Talents(BX20190064).
文摘Flexible power sources featuring high-performance,prominent flexibility and raised safety have received mounting attention in the area of wearable electronic devices.However,many great challenges remain to be overcome,notably the design and fabrication of flexible electrodes with excellent electrochemical performance and matching them with safe and reliable electrolytes.Herein,a facile approach for preparing flexible electrodes,which employs carbon cloth derived from commercial cotton cloth as the substrate of cathode and a flexible anode,is proposed and investigated.The promising cathode(NVPOF@FCC)with high conductivity and outstanding flexibility is prepared by efficiently coating Na_(3)V_(2)(PO_(4))_(2)O_(2)F(NVPOF)on flexible carbon cloth(FCC),which exhibits remarkable electrochemical performance and the significantly improved reaction kinetics.More importantly,a novel flexible quasi-solid-state sodium-ion full battery(QSFB)is feasibly assembled by sandwiching a P(VDF-HFP)-NaClO_(4) gel-polymer electrolyte film between the advanced NVPOF@FCC cathode and FCC anode.And the QSFBs are further evaluated in flexible pouch cells,which not only demonstrates excellent energy-storage performance in aspect of great cycling stability and high-rate capability,but also impressive flexibility and safety.This work offers a feasible and effective strategy for the design of flexible electrodes,paving the way for the progression of practical and sustainable flexible batteries.
