In this paper, the petal-like MoS2/MXene composite has been successfully synthesized by one-step hydrothermal method. With the combination of few-layer MoS2nanosheets and the high conductive MXene substrate, the compo...In this paper, the petal-like MoS2/MXene composite has been successfully synthesized by one-step hydrothermal method. With the combination of few-layer MoS2nanosheets and the high conductive MXene substrate, the composite exhibits enhanced capacities of 165 mAh/g at 50 mA/g and outstanding rate performance of 93 mAh/g at 200 mA/g as a cathode material of Mg batteries. Simultaneously, MXene with high conductivity and abundant surface functional groups is proved to be a promising substrate for the wider design of high performance electrode materials.展开更多
Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons chemistry.However,the reversible Mg^(2+)diffusion in cathode materials is restricted by the ...Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons chemistry.However,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic lattice.Herein,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)ions.Theoretically,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge re-delocalization.Benefiting from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)ions.Accordingly,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 mA h g^(-1)at 50 mA g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.展开更多
Li3Mg（2x）V（2-2x）（PO4）3/C（x=0,0.05,0.1,0.2） composites were synthesized by carbothermic reduction,using a self-made MgNH4PO4/MgHPO4 compound as Mg-doping agent.X-ray diffraction（XRD）,scanning electron microsc...Li3Mg（2x）V（2-2x）（PO4）3/C（x=0,0.05,0.1,0.2） composites were synthesized by carbothermic reduction,using a self-made MgNH4PO4/MgHPO4 compound as Mg-doping agent.X-ray diffraction（XRD）,scanning electron microscope（SEM）,electrochemical performance tests were employed to investigate the effect of Mg doping on Li3V2（PO4）3/C samples.The results showed that a proper quantity of Mg doping was beneficial to the reduction of charge transfer resistance of Li3V2（PO4）3/C compound without changing the lattice structure,which led to larger charge/discharge capacity and better cycle performance especially at high current density.Li3Mg（2x）V（2-2x）（PO4）3/C sample with x=0.05 exhibited a better performance with initial charge/discharge capacity of146/128 mA·h/g and discharge capacity of 115 mA·h/g at 5C,while these two figures were 142/118 mA·h/g and 90 mA·h/g respectively for samples without Mg doping,indicating that a proper amount of doped Mg can improve the electrochemical performance of LVP sample.All of these proved that,as a trial Mg dopant,the synthesized MgNH4PO4/MgHPO4 compound exhibited well doping effect.展开更多
Rechargeable magnesium-ion batteries(MIBs) are favorable substitutes for conventional lithium-ion batteries(LIBs) because of abundant magnesium reserves, a high theoretical energy density, and great inherent safety. O...Rechargeable magnesium-ion batteries(MIBs) are favorable substitutes for conventional lithium-ion batteries(LIBs) because of abundant magnesium reserves, a high theoretical energy density, and great inherent safety. Organic electrode materials with excellent structural tunability,unique coordination reaction mechanisms, and environmental friendliness offer great potential to promote the electrochemical performance of MIBs. However, research on organic magnesium battery cathode materials is still preliminary with many significant challenges to be resolved including low electrical conductivity and unwanted but severe dissolution in useful electrolytes. Herein, we provide a detailed overview of reported organic cathode materials for MIBs. We begin with basic properties such as charge storage mechanisms(e.g., n-, p-, and bipolartype), moving to recent advances in various types of organic cathodes including carbonyl-, nitrogen-, and sulfur-based materials. To shed light on the diverse strategies targeting high-performance Mg-organic batteries, elaborate summaries of various approaches are presented.Generally, these strategies include molecular design, polymerization, mixing with carbon, nanosizing and electrolyte/separator optimization.This review provides insights on exploring high-performance organic cathodes in rechargeable MIBs.展开更多
Rechargeable magnesium batteries(RMBs)are considered the promising candidates for post lithium-ion batteries due to the abundant storage,high capacity,and dendrite-rare characteristic of Mg anode.However,the lack of p...Rechargeable magnesium batteries(RMBs)are considered the promising candidates for post lithium-ion batteries due to the abundant storage,high capacity,and dendrite-rare characteristic of Mg anode.However,the lack of practical electrolytes impedes the development and application of RMBs.Here,through a one-step reaction of LiCl congenital-containing Knochel–Hauser base TMPL(2,2,6,6-tetrame thylpiperidinylmagnesium chloride lithium chloride complex)with Lewis acid AlCl_(3),we successfully synthesized an efficient amino-magnesium halide TMPLA electrolyte.Raman and mass spectroscopy identified that the electrolyte comprises the typical di-nuclear copolymer[Mg_(2)Cl_(3)·6THF]+cation group and[(TMP)2AlCl_(2)]-anion group,further supported by the results of density functional theory calculations(DFT)and the Molecular dynamics(MD)simulations.The TMPLA electrolyte exhibits promising electrochemical performance,including available anodic stability(>2.65 V vs.SS),high ionic conductivity(6.05mS cm^(-1)),and low overpotential(<0.1 V)as well as appropriate Coulombic efficiency(97.3%)for Mg plating/stripping.Both the insertion Mo6S8cathode and conversion Cu S cathode delivered a desirable electrochemical performance with high capacity and good cycling stability based on the TMPLA electrolyte.In particular,when compatible with low cost and easily synthesized Cu S,the Cu S||Mg cell displayed an extremely high discharge capacity of 458.8 mAh g^(-1)for the first cycle and stabilized at 170.2 mAh g^(-1)with high Coulombic efficiency(99.1%)after 50 cycles at 0.05 C.Our work proposes an efficient electrolyte with impressive compatibility with Mg anode and insertion/conversion cathode for practical RMBs and provides a more profound knowledge of the Lewis acid–base reaction mechanisms.展开更多
文摘In this paper, the petal-like MoS2/MXene composite has been successfully synthesized by one-step hydrothermal method. With the combination of few-layer MoS2nanosheets and the high conductive MXene substrate, the composite exhibits enhanced capacities of 165 mAh/g at 50 mA/g and outstanding rate performance of 93 mAh/g at 200 mA/g as a cathode material of Mg batteries. Simultaneously, MXene with high conductivity and abundant surface functional groups is proved to be a promising substrate for the wider design of high performance electrode materials.
基金the financial support of this work by the National Natural Science Foundation of China(No.52034011)the Key R&D Program of Shanxi(No.2019ZDLGY04-05)+2 种基金the National Natural Science Foundation of Shaanxi(No.2019JLZ-01)the Fundamental Research Funds for the Central Universities(No.G2020KY05129)the Research Fund of the State Key Laboratory of Solidification Processing(NPU),China(No.2020-BJ-03)。
文摘Rechargeable Mg-ion batteries(MIBs)have attracted much more attentions by virtue of the high capacity from the two electrons chemistry.However,the reversible Mg^(2+)diffusion in cathode materials is restricted by the strong interactions between the high-polarized bivalent Mg^(2+)ions and anionic lattice.Herein,we design and propose a hetero-structural VO_(2)(R)-VS_(4)cathode,in which the re-delocalized d-electrons can effectively shield the polarity of Mg^(2+)ions.Theoretically,the electrons should spontaneously transfer from VS_(4)to VO_(2)(R)through the interfaces of hetero-structure due to the lower work function value of VS_(4).Furthermore,the internal electrons transfer lead to the electronic injection into VO_(2)(R)from VS_(4)and the partially broken V-V dimers,indicating the presence of lone pair electrons and charge re-delocalization.Benefiting from the shield effect of re-delocalized electrons,and the weakened attraction between cations and O/S anions enables more S^(2-)-S_(2)^(2-)redox groups to participate the electrochemical reactions and compensate the double charge of Mg^(2+)ions.Accordingly,VO_(2)(R)-VS_(4)hetero-structure exhibits a high specific capacity of 554 mA h g^(-1)at 50 mA g^(-1).It is believed that the charge re-delocalization of cathode extremely boost the Mg^(2+)ions migration for the high-capacity of MIBs.
基金Project(2014CB643405)supported by the National Basic Research Program of China
文摘Li3Mg（2x）V（2-2x）（PO4）3/C（x=0,0.05,0.1,0.2） composites were synthesized by carbothermic reduction,using a self-made MgNH4PO4/MgHPO4 compound as Mg-doping agent.X-ray diffraction（XRD）,scanning electron microscope（SEM）,electrochemical performance tests were employed to investigate the effect of Mg doping on Li3V2（PO4）3/C samples.The results showed that a proper quantity of Mg doping was beneficial to the reduction of charge transfer resistance of Li3V2（PO4）3/C compound without changing the lattice structure,which led to larger charge/discharge capacity and better cycle performance especially at high current density.Li3Mg（2x）V（2-2x）（PO4）3/C sample with x=0.05 exhibited a better performance with initial charge/discharge capacity of146/128 mA·h/g and discharge capacity of 115 mA·h/g at 5C,while these two figures were 142/118 mA·h/g and 90 mA·h/g respectively for samples without Mg doping,indicating that a proper amount of doped Mg can improve the electrochemical performance of LVP sample.All of these proved that,as a trial Mg dopant,the synthesized MgNH4PO4/MgHPO4 compound exhibited well doping effect.
基金the support from the National Key Research & Development Program (2022YFB3803700) of ChinaNational Natural Science Foundation (No.52171186)the support from the Center of Hydrogen Science,Shanghai Jiao Tong University。
文摘Rechargeable magnesium-ion batteries(MIBs) are favorable substitutes for conventional lithium-ion batteries(LIBs) because of abundant magnesium reserves, a high theoretical energy density, and great inherent safety. Organic electrode materials with excellent structural tunability,unique coordination reaction mechanisms, and environmental friendliness offer great potential to promote the electrochemical performance of MIBs. However, research on organic magnesium battery cathode materials is still preliminary with many significant challenges to be resolved including low electrical conductivity and unwanted but severe dissolution in useful electrolytes. Herein, we provide a detailed overview of reported organic cathode materials for MIBs. We begin with basic properties such as charge storage mechanisms(e.g., n-, p-, and bipolartype), moving to recent advances in various types of organic cathodes including carbonyl-, nitrogen-, and sulfur-based materials. To shed light on the diverse strategies targeting high-performance Mg-organic batteries, elaborate summaries of various approaches are presented.Generally, these strategies include molecular design, polymerization, mixing with carbon, nanosizing and electrolyte/separator optimization.This review provides insights on exploring high-performance organic cathodes in rechargeable MIBs.
基金financial support from the National Natural Science Foundation of China(Nos.21975159,2157316)the Shanghai Aerospace Science and Technology Innovation Fund(No.SAST2018-117)the Oceanic Interdisciplinary Program of Shanghai Jiao Tong University(No.WH410260401/006)。
文摘Rechargeable magnesium batteries(RMBs)are considered the promising candidates for post lithium-ion batteries due to the abundant storage,high capacity,and dendrite-rare characteristic of Mg anode.However,the lack of practical electrolytes impedes the development and application of RMBs.Here,through a one-step reaction of LiCl congenital-containing Knochel–Hauser base TMPL(2,2,6,6-tetrame thylpiperidinylmagnesium chloride lithium chloride complex)with Lewis acid AlCl_(3),we successfully synthesized an efficient amino-magnesium halide TMPLA electrolyte.Raman and mass spectroscopy identified that the electrolyte comprises the typical di-nuclear copolymer[Mg_(2)Cl_(3)·6THF]+cation group and[(TMP)2AlCl_(2)]-anion group,further supported by the results of density functional theory calculations(DFT)and the Molecular dynamics(MD)simulations.The TMPLA electrolyte exhibits promising electrochemical performance,including available anodic stability(>2.65 V vs.SS),high ionic conductivity(6.05mS cm^(-1)),and low overpotential(<0.1 V)as well as appropriate Coulombic efficiency(97.3%)for Mg plating/stripping.Both the insertion Mo6S8cathode and conversion Cu S cathode delivered a desirable electrochemical performance with high capacity and good cycling stability based on the TMPLA electrolyte.In particular,when compatible with low cost and easily synthesized Cu S,the Cu S||Mg cell displayed an extremely high discharge capacity of 458.8 mAh g^(-1)for the first cycle and stabilized at 170.2 mAh g^(-1)with high Coulombic efficiency(99.1%)after 50 cycles at 0.05 C.Our work proposes an efficient electrolyte with impressive compatibility with Mg anode and insertion/conversion cathode for practical RMBs and provides a more profound knowledge of the Lewis acid–base reaction mechanisms.
