The selection and development of cathode of alkaline zinc batteries(AZBs)is still hindered and often leads to poor rate capability and short cycle life.Here,amorphous hollow nickel-cobalt-based sulfides nanocages with...The selection and development of cathode of alkaline zinc batteries(AZBs)is still hindered and often leads to poor rate capability and short cycle life.Here,amorphous hollow nickel-cobalt-based sulfides nanocages with nanosheet arrays(AM-NCS)are designed and constructed with ZIF-67 as the selftemplate to exchange with Ni^(2+) and S^(2-) by using a two-step ion exchange method.The synthesized AM-NCS possess the high specific capacity(160 m Ah/g at 2 A/g),and the assembled battery has excellent rate performance(146 m Ah/g reversible capacity at 5 A/g).The assembled device has excellent rate performance(155 m Ah/g at 2 A/g)and long cycling stability(7000 cycles,62.5%of initial capacity).The excellent electrochemical properties of the electrode materials are mainly attributed to the unique structure,in particular,polyhedron structure with hollow structure can improve the cyclic stability,and the amorphous structure can expose more reactive sites on the surfaces of nickel,cobalt and sulfur.This work provides a new strategy for the design and fabrication of high performance cathode materials for AZBs.展开更多
Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical application...Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications.Herein,an integrated approach is proposed to fabricate the high-performance rGO/VS_(4)/S cathode composites through a simple one-step solvothermal method,where nano sulfur and VS_(4) particles are uniformly distributed on the conductive rGO matrix.rGO and sulfiphilic VS_(4)provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides(LiPS).Meanwhile,VS_(4) could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS.Correspondingly,the rGO/VS_(4)/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles,with a capacity retention rate of 82.3%.The capacity fade rate could lower to 0.0374%per cycle at 1 C.Moreover,capacity still sustains 795 m Ah/g after 100 cycles in the relatively high-sulfurloading battery(6.5 mg/cm^(2)).Thus,the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li-S batteries.展开更多
With the merits of low cost,environmental benignity,and high safety,aqueous zinc ion batteries(AZIBs)have great potential in the field of energy storage.In this paper,we craft a Co-doped Ni3 S2 with abundant sulfur va...With the merits of low cost,environmental benignity,and high safety,aqueous zinc ion batteries(AZIBs)have great potential in the field of energy storage.In this paper,we craft a Co-doped Ni3 S2 with abundant sulfur vacancies as effective cathode materials(Co-Ni_(3) S_(2-x)) for AZIBs by hydrothermal and chemical reduction method.Notably,cobalt doping and abundant sulfur vacancies can effectively increase the conductivity and the number of active sites for electrochemical reactions,which gives the Co-Ni_(3) S_(2-x) electrode the outstanding capability to energy storage.By coupling Co-Ni_(3) S_(2-x) cathode with Zn anodes to assemble alkaline AZIBs,the Co-Ni_(3) S_(2-x)//Zn full battery exhibits excellent specific capacity(183.9 mAh g^(-1) at 1 A g^(-1),based on cathode mass) and extraordinary cycling durability(72.9% capacity retention after 6000 cycles).First-principles calculations based on density functional theory(DFT) confirm that the Co-Ni_(3) S_(2-x) electrode has strong energy storage capacity and electrochemical stability.The results provide an extremely significant reference in designs of self-supported bimetallic sulfide nanosheets,which have promising applications in high-performance energy storage devices.展开更多
Flexible aqueous energy storage devices with high security and flexibility are crucial for the progress of wearable energy storage.Particularly,aqueous rechargeable Ni-Fe batteries owning a large theoretical capacity,...Flexible aqueous energy storage devices with high security and flexibility are crucial for the progress of wearable energy storage.Particularly,aqueous rechargeable Ni-Fe batteries owning a large theoretical capacity,low cost and outstanding safety characteristics have emerged as a promising candidate for flexible aqueous energy storage devices.Herein,Cu-doped Fe_(3)O_(4)(CFO)with 3D coral structure was prepared by doping Cu^(2+) based on Fe_(3)O_(4)nanosheets(FO).Furthermore,the Fe-based anode material(CFPO)grown on carbon fibers was obtained by reconstructing the surface of CFO to form a low-crystallization shell which can enhance the ion transport.Excitingly,the newly developed CFPO electrode as an innovative anode material further exhibited a high capacity of 117.5 mAh g^(-1)(or 423 F g^(-1))at 1 A g^(-1).Then,the assembled aqueous Ni-Fe batteries with a high cell-voltage output of 1.6 V deliver a high capacity of 49.02 mAh g^(-1) at 1 A g^(-1) and retention ratio of 96.8%for capacitance after 10000 continuous cycles.What’s more,the aqueous quasi-solid-state batteries present a remarkable maximal energy density of 45.6 Wh kg^(-1) and a power density of 12 kW kg^(-1).This work provides an innovative and feasible way and optimization idea for the design of high-performance Fe-based anodes,and may promote the development of a new generation of flexible aqueous Ni-Fe batteries.展开更多
Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since ...Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries.展开更多
Ni0.5Co0.5（OH）2 nanosheets coated CuCo2O4 nanoneedles arrays were successfully designed and synthe- sized on carbon fabric. The core/shell nanoarchitectures directly served as the binder-free electrode with a superi...Ni0.5Co0.5（OH）2 nanosheets coated CuCo2O4 nanoneedles arrays were successfully designed and synthe- sized on carbon fabric. The core/shell nanoarchitectures directly served as the binder-free electrode with a superior capacity of 295.6 mAh g-1 at 1 Ag-1, which still maintained 220 mAh g-1 even at the high current density of 40 A g-l, manifesting their enormous potential in hybrid supercapacitor devices. The asassembled CuCo2O4@Ni0.5Co0.5（OH）2]]AC hybrid supercapacitor device exhibited favorable properties with the specific capacitance as high as 90 F g 1 at 1 A g-1 and the high energy density of 32 Wh kg 1 at the power density of 800 Wkg-1. Furthermore, the as-assembled device also delivered excellent cycling performance （retaining 91.9% of the initial capacitance after 12,000 cycles at 8 A g 1） and robust mechanical stability and flexibility, implying the huge potential of present hierarchical electrodes in energy storage devices.展开更多
Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation an...Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation and the Na^(+)/vacancy ordering lowers their redox kinetics.Here,we rationally propose a compositionally graded P2-type cathode,where nickel(Ni)and manganese(Mn)fractions decrease gradually,and cobalt(Co)content increases contiguously from the inside to the outside of a secondary particle.Inside these particles,the Ni/Mn-based compound delivers high capacity and high voltage.On the surface of particles,the Co/Mn-based solid solution offers a stable buffer matrix.Benefiting from these synergistic effects,this graded P2-type cathode shows the elimination of P2–O2 transformation even when charged to 4.4 V,which enables good structural stability,maintaining capacity retention reaching~80%within 300 cycles.Moreover,the Na^(+)/vacancy ordering superstructure is further suppressed,and the Na^(+)diffusion kinetics is significantly improved.The proposed graded structure with optimized chemical composition offers a new perspective for eliminating the unwanted phase transition and thus enhancing the electrochemistry of high-voltage layered cathodes for advanced NIBs.展开更多
基金the Independent Cultivation Program of Innovation Team of Ji’nan City(No.2019GXRC011)National Natural Science Foundation of China(No.51802177)Natural Science Foundation of Shandong Province(No.ZR2020QE062)。
文摘The selection and development of cathode of alkaline zinc batteries(AZBs)is still hindered and often leads to poor rate capability and short cycle life.Here,amorphous hollow nickel-cobalt-based sulfides nanocages with nanosheet arrays(AM-NCS)are designed and constructed with ZIF-67 as the selftemplate to exchange with Ni^(2+) and S^(2-) by using a two-step ion exchange method.The synthesized AM-NCS possess the high specific capacity(160 m Ah/g at 2 A/g),and the assembled battery has excellent rate performance(146 m Ah/g reversible capacity at 5 A/g).The assembled device has excellent rate performance(155 m Ah/g at 2 A/g)and long cycling stability(7000 cycles,62.5%of initial capacity).The excellent electrochemical properties of the electrode materials are mainly attributed to the unique structure,in particular,polyhedron structure with hollow structure can improve the cyclic stability,and the amorphous structure can expose more reactive sites on the surfaces of nickel,cobalt and sulfur.This work provides a new strategy for the design and fabrication of high performance cathode materials for AZBs.
基金supported by the National Natural Science Foundation of China(No.21905289)the Independent Cultivation Program of Innovation Team of Ji’nan City(No.2019GXRC011)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2020QE062)China Postdoctoral Science Foundation(No.2021T140268)。
文摘Lithium-sulfur(Li-S)battery is labeled as a promising high-energy-density battery system,but some inherent drawbacks of sulfur cathode materials using relatively complicated techniques impair the practical applications.Herein,an integrated approach is proposed to fabricate the high-performance rGO/VS_(4)/S cathode composites through a simple one-step solvothermal method,where nano sulfur and VS_(4) particles are uniformly distributed on the conductive rGO matrix.rGO and sulfiphilic VS_(4)provide electron transfer skeleton and physical/chemical anchor for soluble lithium polysulfides(LiPS).Meanwhile,VS_(4) could also act as an electrochemical mediator to efficiently enhance the utilization and reversible conversion of LiPS.Correspondingly,the rGO/VS_(4)/S composites maintain a high reversible capacity of 969 mAh/g at 0.2 C after 100 cycles,with a capacity retention rate of 82.3%.The capacity fade rate could lower to 0.0374%per cycle at 1 C.Moreover,capacity still sustains 795 m Ah/g after 100 cycles in the relatively high-sulfurloading battery(6.5 mg/cm^(2)).Thus,the suggested method in configuring the sulfur-based composites is demonstrated a simple and efficient strategy to construct the high-performance Li-S batteries.
基金financially supported by the Independent Cultivation Program of Innovation Team of Ji’nan City (No.2019GXRC011)National Natural Science Foundation of China(Nos. 21707043, 51908242)the Natural Science Foundation of Shandong Province (No. ZR2017BEE005)。
文摘With the merits of low cost,environmental benignity,and high safety,aqueous zinc ion batteries(AZIBs)have great potential in the field of energy storage.In this paper,we craft a Co-doped Ni3 S2 with abundant sulfur vacancies as effective cathode materials(Co-Ni_(3) S_(2-x)) for AZIBs by hydrothermal and chemical reduction method.Notably,cobalt doping and abundant sulfur vacancies can effectively increase the conductivity and the number of active sites for electrochemical reactions,which gives the Co-Ni_(3) S_(2-x) electrode the outstanding capability to energy storage.By coupling Co-Ni_(3) S_(2-x) cathode with Zn anodes to assemble alkaline AZIBs,the Co-Ni_(3) S_(2-x)//Zn full battery exhibits excellent specific capacity(183.9 mAh g^(-1) at 1 A g^(-1),based on cathode mass) and extraordinary cycling durability(72.9% capacity retention after 6000 cycles).First-principles calculations based on density functional theory(DFT) confirm that the Co-Ni_(3) S_(2-x) electrode has strong energy storage capacity and electrochemical stability.The results provide an extremely significant reference in designs of self-supported bimetallic sulfide nanosheets,which have promising applications in high-performance energy storage devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.51802177)Independent Cultivation Program of Innovation Team of Ji’nan City(Grant No.2019GXRC011)。
文摘Flexible aqueous energy storage devices with high security and flexibility are crucial for the progress of wearable energy storage.Particularly,aqueous rechargeable Ni-Fe batteries owning a large theoretical capacity,low cost and outstanding safety characteristics have emerged as a promising candidate for flexible aqueous energy storage devices.Herein,Cu-doped Fe_(3)O_(4)(CFO)with 3D coral structure was prepared by doping Cu^(2+) based on Fe_(3)O_(4)nanosheets(FO).Furthermore,the Fe-based anode material(CFPO)grown on carbon fibers was obtained by reconstructing the surface of CFO to form a low-crystallization shell which can enhance the ion transport.Excitingly,the newly developed CFPO electrode as an innovative anode material further exhibited a high capacity of 117.5 mAh g^(-1)(or 423 F g^(-1))at 1 A g^(-1).Then,the assembled aqueous Ni-Fe batteries with a high cell-voltage output of 1.6 V deliver a high capacity of 49.02 mAh g^(-1) at 1 A g^(-1) and retention ratio of 96.8%for capacitance after 10000 continuous cycles.What’s more,the aqueous quasi-solid-state batteries present a remarkable maximal energy density of 45.6 Wh kg^(-1) and a power density of 12 kW kg^(-1).This work provides an innovative and feasible way and optimization idea for the design of high-performance Fe-based anodes,and may promote the development of a new generation of flexible aqueous Ni-Fe batteries.
基金the Hong Kong Polytechnic University(Q-CDBG),the Science and Technology Program of Guangdong Province of China(2020A0505090001)the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.PolyU152178/20E)+2 种基金the National Natural Science Foundation of China(22379052)the Natural Science Foundation of Guangdong(No.2022A1515011667)China Postdoctoral Science Foundation(2021T140268).
文摘Inactive elemental doping is commonly used to improve the structural stability of high-voltage layered transition-metal oxide cathodes.However,the one-step co-doping strategy usually results in small grain size since the low diffusivity ions such as Ti^(4+)will be concentrated on grain boundaries,which hinders the grain growth.In order to synthesize large single-crystal layered oxide cathodes,considering the different diffusivities of different dopant ions,we propose a simple two-step multi-element co-doping strategy to fabricate core–shell structured LiCoO_(2)(CS-LCO).In the current work,the high-diffusivity Al^(3+)/Mg^(2+)ions occupy the core of single-crystal grain while the low diffusivity Ti^(4+)ions enrich the shell layer.The Ti^(4+)-enriched shell layer(~12 nm)with Co/Ti substitution and stronger Ti–O bond gives rise to less oxygen ligand holes.In-situ XRD demonstrates the constrained contraction of c-axis lattice parameter and mitigated structural distortion.Under a high upper cut-off voltage of 4.6 V,the single-crystal CS-LCO maintains a reversible capacity of 159.8 mAh g^(−1)with a good retention of~89%after 300 cycles,and reaches a high specific capacity of 163.8 mAh g^(−1)at 5C.The proposed strategy can be extended to other pairs of low-(Zr^(4+),Ta^(5+),and W6+,etc.)and high-diffusivity cations(Zn^(2+),Ni^(2+),and Fe^(3+),etc.)for rational design of advanced layered oxide core–shell structured cathodes for lithium-ion batteries.
基金supported by the National Natural Science Foundation of China (51672109,21505050)Natural Science Foundation of Shandong Province for Excellent Young Scholars (ZR2016JL015)+2 种基金the National Basic Research Program of China (2015CB932600)the Program for Huazhong University of Science and Technology (HUST) Interdisplinary Innovation Team (2015ZDTD038)the Fundamental Research Funds for the Central University
文摘Ni0.5Co0.5（OH）2 nanosheets coated CuCo2O4 nanoneedles arrays were successfully designed and synthe- sized on carbon fabric. The core/shell nanoarchitectures directly served as the binder-free electrode with a superior capacity of 295.6 mAh g-1 at 1 Ag-1, which still maintained 220 mAh g-1 even at the high current density of 40 A g-l, manifesting their enormous potential in hybrid supercapacitor devices. The asassembled CuCo2O4@Ni0.5Co0.5（OH）2]]AC hybrid supercapacitor device exhibited favorable properties with the specific capacitance as high as 90 F g 1 at 1 A g-1 and the high energy density of 32 Wh kg 1 at the power density of 800 Wkg-1. Furthermore, the as-assembled device also delivered excellent cycling performance （retaining 91.9% of the initial capacitance after 12,000 cycles at 8 A g 1） and robust mechanical stability and flexibility, implying the huge potential of present hierarchical electrodes in energy storage devices.
基金funded by the National Natural Science Foundation of China(No.52102252)the Natural Science Foundation of Shandong Province(No.ZR2021QB052)China Postdoctoral Science Foundation(No.2021T140268).
文摘Layered P2-type cathodes with high voltage,large capacity,and easy synthesis show great potential for developing sodium(Na)-ion batteries(NIBs).However,the P2–O2 phase transition makes their structural degradation and the Na^(+)/vacancy ordering lowers their redox kinetics.Here,we rationally propose a compositionally graded P2-type cathode,where nickel(Ni)and manganese(Mn)fractions decrease gradually,and cobalt(Co)content increases contiguously from the inside to the outside of a secondary particle.Inside these particles,the Ni/Mn-based compound delivers high capacity and high voltage.On the surface of particles,the Co/Mn-based solid solution offers a stable buffer matrix.Benefiting from these synergistic effects,this graded P2-type cathode shows the elimination of P2–O2 transformation even when charged to 4.4 V,which enables good structural stability,maintaining capacity retention reaching~80%within 300 cycles.Moreover,the Na^(+)/vacancy ordering superstructure is further suppressed,and the Na^(+)diffusion kinetics is significantly improved.The proposed graded structure with optimized chemical composition offers a new perspective for eliminating the unwanted phase transition and thus enhancing the electrochemistry of high-voltage layered cathodes for advanced NIBs.
