The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay ...The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy （EIS） analysis.展开更多
Sodium-ion batteries are considered as a promising candidate for lithium-ion batteries due to abundant sodium resources and similar intercalation chemistry.Hard carbon derived from biomass with the virtue of abundance...Sodium-ion batteries are considered as a promising candidate for lithium-ion batteries due to abundant sodium resources and similar intercalation chemistry.Hard carbon derived from biomass with the virtue of abundance and renewability is a cost-effective anode material.Herein,hard carbon is derived from renewable bagasse through a simple two-step method combining mechanical ball milling with carbonization.The hard carbon electrodes exhibit superior electrochemical performance with a high reversible capacity of 315 mA∙h/g.Furthermore,the initial capacity of the full cell,HC//NaMn0.4Ni0.4Ti0.1Mg0.1O2,is 253 mA∙h/g and its capacity retention rate is 77%after 80 cycles,which further verifies its practical application.The simple and low-cost preparation process,as well as excellent electrochemical properties,demonstrates that hard carbon derived from bagasse is a promising anode for sodium-ion batteries.展开更多
Developing high-performance lithium ion batteries(LIBs)using manganese oxides as anodes is attractive due to their high theoretical capacity and abundant resources.Herein,we report a facile synthesis of hierarchical s...Developing high-performance lithium ion batteries(LIBs)using manganese oxides as anodes is attractive due to their high theoretical capacity and abundant resources.Herein,we report a facile synthesis of hierarchical spherical MnO2 containing coherent amorphous/crystalline domained by a simple yet effective redox precipitation reaction at room temperature.Further,flower-like CoMn2O4 constructed by single-crystalline spinel nanosheets has been fabricated using MnO2 as precursor.This mild methodology avoids undesired particle aggregation and loss of active surface area in conventional hydrothermal or solid-state processes.Moreover,both MnO2 and CoMn2O4 nanosheets manifest superior lithium-ion storage properties,rendering them promising applications in LIBs and other energy-related fields.展开更多
Li4Ti5O12/C composite materials were synthesized by two-step solid state reaction method with glucose, sucrose, and starch as carbon sources, respectively. The effects of carbon sources on the structure, morphology, a...Li4Ti5O12/C composite materials were synthesized by two-step solid state reaction method with glucose, sucrose, and starch as carbon sources, respectively. The effects of carbon sources on the structure, morphology, and electrochemical performance of Li4Ti5O12/C composite materials were investigated by SEM, XRD and electrochemical tests. The results indicate that carbon sources have almost no effect on the structure of Li4Ti5O12/C composite materials. The initial discharge capacities of the Li4Ti1O12/C composite materials are slightly lower than those of as-synthesized Li4Ti5O12. However, Li4Ti5O12/C composite materials show better electrochemical rate performance than the as-synthesized Li4Ti5O12. The capacity retention （79%） of the Li4Ti5O12/C composite materials with starch as carbon source, is higher than that of Li4Ti5O12/C composite materials with glucose and sucrose as carbon source at current rate of 2.0C.展开更多
The graphite was modified by mild oxidation, and the effects of modification temperature and soaking time on the characteristics of graphite were investigated. The structure and characteristics of the graphite were de...The graphite was modified by mild oxidation, and the effects of modification temperature and soaking time on the characteristics of graphite were investigated. The structure and characteristics of the graphite were determined by X-ray diffraction, scanning electron microscopy, BET surface area, particle size analysis and electrochemical measurements. The results show that the modified graphite has a better-developed crystallite structure, larger average particle diameter, smaller surface area, and better electrochemical characteristics than the untrented graphite. The sample mild-oxidized at 600℃ for 3h has the best electrochemical performances with a reversible capacity of 304.5mA·h/g, a irreversible capacity of 66.4mA·h/g, and a initial coulombic efficiency of 82.1%. The charge/discharge properties and a cycling stability of the prototype lithium ion batteries with modified graphite as anodes are improved. Its capacity retention ratio at the 200th cycle is enhanced from 66.75% to 90.15%.展开更多
A skutterudite-related antimonide, CoFe3Sb12,was prepared with vacuum melting.XRD analysis showed the material contained Sb, FeSb2, CoSb2 and CoSb3 phases.The electrochemical properties of the ball-milled CoFe3Sb12-10...A skutterudite-related antimonide, CoFe3Sb12,was prepared with vacuum melting.XRD analysis showed the material contained Sb, FeSb2, CoSb2 and CoSb3 phases.The electrochemical properties of the ball-milled CoFe3Sb12-10wt% graphite composite were studied using pure lithium as the reference electrode. A maximal lithium inserting capacity of about 860 mAh/g was obtained in the first cycle.The reversible capacity of the material was about 560mAh/g in the first cycle and decreased to ca.320 mAh/g and 250 mAh/g after 10 and 20 cycles respectively.Ex-situ XRD analyses showed that the antimonides in the pristine material were decomposed after the first discharge and that antimony was the active element for lithium to insert into the host material.展开更多
Principally the basis of ISE is selecting of a support solid matrix and a nonsoluble compound or complexes of insighted cation, mixed with this solid. For preparing the ISE membranes there are some materials such PVC,...Principally the basis of ISE is selecting of a support solid matrix and a nonsoluble compound or complexes of insighted cation, mixed with this solid. For preparing the ISE membranes there are some materials such PVC, PE, organic polyelectrolytes, conducting polymers and inorganic compounds. The black white microscope photos are included, too. Detailed schemes and pictures of the electrodes and correlations were shown in the following article. Results are seen compatible for construction of the versatile ISE electrodes.展开更多
The objective of this research was to investigate the optimum condition for treatment of textile industrial wastewater from water jet loom machine by chemical coagulation and electrocoagulation methods. The variables ...The objective of this research was to investigate the optimum condition for treatment of textile industrial wastewater from water jet loom machine by chemical coagulation and electrocoagulation methods. The variables of chemical coagulation method were type and amount of chemicals, pH and stirring rate. For electrocoagulation method, the variables were electrode materials, electric potential and contact time. It was found that the optimum condition of chemical coagulation method was 10% （w/w） of aqueous solution of aluminum sulphate 80 mL and 0.01% （w/w） of aqueous solution of coagulant aids, cationic polymer 32 mL per 4 L of wastewater at oH 8. The mixture solution was rapidly stirred with 120 rpm for 1 min and then slowly stirred with 20 rpm for 20 rain. The removal efficiency of turbidity, COD and oil content were 88.88%, 85.20% and 77.72%, respectively. For electrocoagulation method, the optimum condition was using aluminum electrode with 35 V and 150 min of contact time. The removal efficiency of turbidity, COD and oil content were 98.86%, 91.63% and 89.84%, respectively. It can be concluded from this study that the textile industrial wastewater treatment from water jet loom machine with electrocoagulation method is more efficient than that with chemical coagulation method.展开更多
This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the...This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the advantages in slide-film damping and large vibration amplitude, such a device makes atmospheric packaging a low-cost option for practical manufacture. In this letter, we present the operating principles and specifications, the design structure, as well as the finite element simulation. Computational analysis shows that our design obtains good results in device parameters setting, while its simplicity and low-cost features make it an attractive solution for applications.展开更多
In this work, SiO2 nanoplates with opened macroporous structure on carbon layer （C-mSiO2） have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell...In this work, SiO2 nanoplates with opened macroporous structure on carbon layer （C-mSiO2） have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 （based on the total mass of silica and the two carbon shells）, which is higher than those of C-mSiO2 （391 mA.h.g 1） spheres with an outer porous SiO2 layer, C-SiO2-C （370 mA-h.g-1） hollow spheres with a middle solid Si02 layer, and C-SiO2 （319.8 mA·h-g-1） spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area （246.7 m2·g- 1 ） and pore volume （0.441 cm3· g-1） of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction.展开更多
Experimental research of anode current and anode voltage influence on the speed of decaying plasma resistance change and the time ofthyratron cutoff. Anode current resistance increase is shown to cause thyratron cutof...Experimental research of anode current and anode voltage influence on the speed of decaying plasma resistance change and the time ofthyratron cutoff. Anode current resistance increase is shown to cause thyratron cutoff time increase in case of fixed anode voltage. In turn anode voltage increase in case of fixed anode current causes earlier increase of decaying plasma resistance growth speed and quicker apparatus cutoff：展开更多
In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability...In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.展开更多
Currently, many organic materials are being considered as electrode materials and display good electrochemical behavior. However, the most critical issues related to the wide use of organic electrodes are their low th...Currently, many organic materials are being considered as electrode materials and display good electrochemical behavior. However, the most critical issues related to the wide use of organic electrodes are their low thermal stability and poor cycling performance due to their high solubility in electrolytes. Focusing on one of the most conventional carboxylate organic materials, namely lithium terephthalate Li2CsH4O4, we tackle these typical disadvantages via modifying its molecular structure by cation substitution. CaCsH4O4 and A12（C8H4O4）3 are prepared via a facile cation exchange reaction. Of these, CaCsH4O4 presents the best cycling performance with thermal stability up to 570℃ and capacity of 399 mA.h.g-1, without any capacity decay in the voltage window of 0.005-3.0 V. The molecular, crystal structure, and morphology of CaCsH4O4 are retained during cycling. This cation-substitution strategy brings new perspectives in the synthesis of new materials as well as broadening the applications of organic materials in Li/Na-ion batteries.展开更多
We report a facile, two-step hydrothermal synthesis of a novel Co304/a-Fe2O3 branched nanowire heterostructure, which can serve as a good candidate for lithium-ion battery anodes with high Li＋ storage capacity and st...We report a facile, two-step hydrothermal synthesis of a novel Co304/a-Fe2O3 branched nanowire heterostructure, which can serve as a good candidate for lithium-ion battery anodes with high Li＋ storage capacity and stability. The single-crystalline, primary C0304 nanowire trunk arrays directly grown on Ti substrates allow for efficient electrical and ionic transport. The secondary a-Fe2O3 branches provide enhanced surface area and high theoretical Li＋ storage capacity, and can also serve as volume spacers between neighboring Co3O4 NW arrays to maintain electrolyte penetration as well as reduce the aggregation during Li＋ intercalation, thus leading to improved electrochemical energy storage performance.展开更多
Red phosphorus has received remarkable attention as a promising anode material for sodium ion batteries(NIBs) due to its high theoretical capacity. However, its practical application has been impeded by its intrinsic ...Red phosphorus has received remarkable attention as a promising anode material for sodium ion batteries(NIBs) due to its high theoretical capacity. However, its practical application has been impeded by its intrinsic low electronic conductivity and large volume variations during sodiation/desodiation process. Here, we design a composite to confine nanosized red phosphorus into the hierarchically porous carbon(HPC) walls by a vaporization-condensation strategy. The mass loading of P in the HPC/P composite is optimized to deliver a reversible specific capacity of 2,202 m Ah/gpbased on the mass of red P(836 m Ah/gcompositebased on the total composite mass), a high capacity retention over 77% after100 cycles, and excellent rate performance of 929 m Ah/gpat 2 C. The hierarchical porous carbon serves as the conductive networks, downsize the red phosphorus to nanoscale, and provide free space to accommodate the large volume expansions. The suppressed mechanical failure of the red phosphorus also enhances the stability of solid-electrolyte interface(SEI) layer, which is confirmed by the microscopy and impedance spectroscopy after the cycling tests. Our studies provide a feasible approach for potentially viable high-capacity NIB anode.展开更多
Titanium niobium oxides emerge as promising anode materials with potential for applications in lithium ion batteries with high safety and high energy density.However,the innate low electronic conductivity of such a co...Titanium niobium oxides emerge as promising anode materials with potential for applications in lithium ion batteries with high safety and high energy density.However,the innate low electronic conductivity of such a composite oxide seriously limits its practical capacity,which becomes a serious concern especially when a high rate charge/discharge capability is expected.Here,using a modified template-assisted synthesis protocol,which features an in-situ entrapment of both titanium and niobium species during the formation of polymeric microsphere followed by a pyrolysis process,we succeed in preparing hollow microspheres of titanium niobium oxide with high efficiency in structural control.When used as an anode material,the structurally-controlled hollow sample delivers high reversible capacity(103.7 m A h g^(-1)at 50 C)and extraordinary cycling capability especially at high charge/discharge currents(164.7 m A h g^(-1)after 500 cycles at 10 C).展开更多
Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic ele...Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic electrolyte. Room temperature ionic liquids(RTILs) have been considered as appealing candidates for the electrolytes in Li-S batteries. We investigated the effect of cations in RTILs on the electrochemical performance for Li-S batteries. Ex situ investigation of lithium anode for Li-S batteries indicates that during the discharge/charge process the RTIL with N-methyl-N-propylpyrrolidine cations(P13) can effectively suppress the dissolution of the polysulfides, whereas the RTIL with 1-methyl-3-propyl imidazolium cation(PMIM) barely alleviates the shuttling problem. With 0.5 mol L-1 LiTFSI/P13 TFSI as the electrolyte of Li-S battery, the ketjen black/ sulfur cathode material exhibits high capacity and remarkable cycling stability, which promise the application of the P13-based RTILs in Li-S batteries.展开更多
This review outlines the developments and recent progress in metal-assisted chemical etching of silicon, summarizing a variety of fundamental and innovative processes and etching methods that form a wide range of nano...This review outlines the developments and recent progress in metal-assisted chemical etching of silicon, summarizing a variety of fundamental and innovative processes and etching methods that form a wide range of nanoscale silicon structures. The use of silicon as an anode for Li-ion batteries is also reviewed, where factors such as film thickness, doping, alloying, and their response to reversible lithiation processes are summarized and discussed with respect to battery cell performance. Recent advances in improving the performance of silicon-based anodes in Li-ion batteries are also discussed. The use of a variety of nanostructured silicon structures formed by many different methods as Li-ion battery anodes is outlined, focusing in particular on the influence of mass loading, core-shell structure, conductive additives, and other parameters. The influence of porosity, dopant type, and doping level on the electrochemical response and cell performance of the silicon anodes are detailed based on recent findings. Perspectives on the future of silicon and related materials, and their compositional and structural modifications for energy storage via several electrochemical mechanisms, are also provided.展开更多
Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, us...Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, usually exhibit reversible host rearrangement between P-type and O-type stacking upon charge/discharge. Herein we demonstrate that such host rearrangement is unfavorable and can be suppressed by introducing transition-metal ions into sodium layers. The electrode with stabilized P3-type stacking delivers superior rate capability, high energy efficiency, and excellent cycling performance. Owing to the cation-mixing nature, it performs the lowest lattice strain among all reported cathodes for sodium-ion batteries. Our findings highlight the significance of a stable host for sodium-ion storage and moreover underline the fundamental distinction in material design strategy between lithium-and sodium-ion batteries.展开更多
基金Project(RDCPJ346365-06)supported by the Natural Sciences and Engineering Research Council of CanadaProject(51208193)supported by the National Natural Science Foundation of ChinaProject(11jj6034)supported by the Hunan Provincial Natural Science Foundation
文摘The effect of MnO4- and silver content on electrochemical behaviour of five commercial Pb-Ag alloy anodes was studied in acid zinc sulphate electrolyte with and without MnO4- ions at 38 °C during potential decay periods. When the anodes were immersed into acid zinc sulphate electrolyte without MnO4- ions, the Pb-0.72%Ag anode entered complete passivation state in the shortest time among the five anodes, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by measurement of open circuit potential. During immersion of the anodes, MnO4 ions accelerated the passivation and increased the corrosion current density of the anodes. After immersion in zinc electrolyte with MnO4-, the anode Pb-0.72%Ag had the best corrosion resistance, followed by anodes Pb-0.67%Ag, Pb-0.60%Ag, then the close anodes Pb-0.58%Ag and Pb-0.29%Ag-0.1%Ca by the electrochemical impedance spectroscopy （EIS） analysis.
基金Projects(51661009,51761007)supported by the National Natural Science Foundation of China,Projects(2019GXNSFDA245014,2016GXNSFGA380001)supported by the Natural Science Foundation of Guangxi Province,China,Projects(2019AC20164,2019AC20053)supported by the Science and Technology Base and Talent Special Project of Guangxi Province,China。
文摘Sodium-ion batteries are considered as a promising candidate for lithium-ion batteries due to abundant sodium resources and similar intercalation chemistry.Hard carbon derived from biomass with the virtue of abundance and renewability is a cost-effective anode material.Herein,hard carbon is derived from renewable bagasse through a simple two-step method combining mechanical ball milling with carbonization.The hard carbon electrodes exhibit superior electrochemical performance with a high reversible capacity of 315 mA∙h/g.Furthermore,the initial capacity of the full cell,HC//NaMn0.4Ni0.4Ti0.1Mg0.1O2,is 253 mA∙h/g and its capacity retention rate is 77%after 80 cycles,which further verifies its practical application.The simple and low-cost preparation process,as well as excellent electrochemical properties,demonstrates that hard carbon derived from bagasse is a promising anode for sodium-ion batteries.
基金Project(JCYJ20170817110251498)supported by the Basic Research Project of the Science and Technology Innovation Commission of Shenzhen,ChinaProject(2016TQ03C919)supported by the Guangdong Special Support for the Science and Technology Leading Young Scientist,ChinaProject(21603094)supported by the National Natural Science Foundation of China
文摘Developing high-performance lithium ion batteries(LIBs)using manganese oxides as anodes is attractive due to their high theoretical capacity and abundant resources.Herein,we report a facile synthesis of hierarchical spherical MnO2 containing coherent amorphous/crystalline domained by a simple yet effective redox precipitation reaction at room temperature.Further,flower-like CoMn2O4 constructed by single-crystalline spinel nanosheets has been fabricated using MnO2 as precursor.This mild methodology avoids undesired particle aggregation and loss of active surface area in conventional hydrothermal or solid-state processes.Moreover,both MnO2 and CoMn2O4 nanosheets manifest superior lithium-ion storage properties,rendering them promising applications in LIBs and other energy-related fields.
基金Project(2007BAE12B01) supported by the National Key Technology Research and Development Program of China
文摘Li4Ti5O12/C composite materials were synthesized by two-step solid state reaction method with glucose, sucrose, and starch as carbon sources, respectively. The effects of carbon sources on the structure, morphology, and electrochemical performance of Li4Ti5O12/C composite materials were investigated by SEM, XRD and electrochemical tests. The results indicate that carbon sources have almost no effect on the structure of Li4Ti5O12/C composite materials. The initial discharge capacities of the Li4Ti1O12/C composite materials are slightly lower than those of as-synthesized Li4Ti5O12. However, Li4Ti5O12/C composite materials show better electrochemical rate performance than the as-synthesized Li4Ti5O12. The capacity retention （79%） of the Li4Ti5O12/C composite materials with starch as carbon source, is higher than that of Li4Ti5O12/C composite materials with glucose and sucrose as carbon source at current rate of 2.0C.
基金Project (2002 87) surported by Key Problem Study Plan of Science and Technology of Hunan Province
文摘The graphite was modified by mild oxidation, and the effects of modification temperature and soaking time on the characteristics of graphite were investigated. The structure and characteristics of the graphite were determined by X-ray diffraction, scanning electron microscopy, BET surface area, particle size analysis and electrochemical measurements. The results show that the modified graphite has a better-developed crystallite structure, larger average particle diameter, smaller surface area, and better electrochemical characteristics than the untrented graphite. The sample mild-oxidized at 600℃ for 3h has the best electrochemical performances with a reversible capacity of 304.5mA·h/g, a irreversible capacity of 66.4mA·h/g, and a initial coulombic efficiency of 82.1%. The charge/discharge properties and a cycling stability of the prototype lithium ion batteries with modified graphite as anodes are improved. Its capacity retention ratio at the 200th cycle is enhanced from 66.75% to 90.15%.
文摘A skutterudite-related antimonide, CoFe3Sb12,was prepared with vacuum melting.XRD analysis showed the material contained Sb, FeSb2, CoSb2 and CoSb3 phases.The electrochemical properties of the ball-milled CoFe3Sb12-10wt% graphite composite were studied using pure lithium as the reference electrode. A maximal lithium inserting capacity of about 860 mAh/g was obtained in the first cycle.The reversible capacity of the material was about 560mAh/g in the first cycle and decreased to ca.320 mAh/g and 250 mAh/g after 10 and 20 cycles respectively.Ex-situ XRD analyses showed that the antimonides in the pristine material were decomposed after the first discharge and that antimony was the active element for lithium to insert into the host material.
文摘Principally the basis of ISE is selecting of a support solid matrix and a nonsoluble compound or complexes of insighted cation, mixed with this solid. For preparing the ISE membranes there are some materials such PVC, PE, organic polyelectrolytes, conducting polymers and inorganic compounds. The black white microscope photos are included, too. Detailed schemes and pictures of the electrodes and correlations were shown in the following article. Results are seen compatible for construction of the versatile ISE electrodes.
文摘The objective of this research was to investigate the optimum condition for treatment of textile industrial wastewater from water jet loom machine by chemical coagulation and electrocoagulation methods. The variables of chemical coagulation method were type and amount of chemicals, pH and stirring rate. For electrocoagulation method, the variables were electrode materials, electric potential and contact time. It was found that the optimum condition of chemical coagulation method was 10% （w/w） of aqueous solution of aluminum sulphate 80 mL and 0.01% （w/w） of aqueous solution of coagulant aids, cationic polymer 32 mL per 4 L of wastewater at oH 8. The mixture solution was rapidly stirred with 120 rpm for 1 min and then slowly stirred with 20 rpm for 20 rain. The removal efficiency of turbidity, COD and oil content were 88.88%, 85.20% and 77.72%, respectively. For electrocoagulation method, the optimum condition was using aluminum electrode with 35 V and 150 min of contact time. The removal efficiency of turbidity, COD and oil content were 98.86%, 91.63% and 89.84%, respectively. It can be concluded from this study that the textile industrial wastewater treatment from water jet loom machine with electrocoagulation method is more efficient than that with chemical coagulation method.
基金Supported by the National Natural Science Foundation of China (No.60172001).
文摘This letter proposes a novel design of a Micro Electro Mechanical System （MEMS） device featuring a metal grating vibratory mierostructure driven by electrostatic force to sense the spatial electric field. Due to the advantages in slide-film damping and large vibration amplitude, such a device makes atmospheric packaging a low-cost option for practical manufacture. In this letter, we present the operating principles and specifications, the design structure, as well as the finite element simulation. Computational analysis shows that our design obtains good results in device parameters setting, while its simplicity and low-cost features make it an attractive solution for applications.
基金Supported by the National Science Funding for Distinguished Young Scholars of China(21125628)National Natural Science Foundation of China(21476044)the Fundamental Research Funds for the Central Universities(DUT15QY08)
文摘In this work, SiO2 nanoplates with opened macroporous structure on carbon layer （C-mSiO2） have been obtained by dissolving and subsequent ingrowing the outer solid SiO2 layer of the aerosol-based C-SiO2 double-shell hollow spheres. Subsequently, triple-shell C-mSiO2-C hollow spheres were successfully prepared after coating the C- mSiO2 templates by the carbon layer from the carbonization of sucrose. When being applied as the anode material fur lithium-ion batteries, the C-mSiO2-C triple-shell hollow spheres deliver a high capacity of 501 mA. h.g- 1 after 100 cycles at 500 mA.g-1 （based on the total mass of silica and the two carbon shells）, which is higher than those of C-mSiO2 （391 mA.h.g 1） spheres with an outer porous SiO2 layer, C-SiO2-C （370 mA-h.g-1） hollow spheres with a middle solid Si02 layer, and C-SiO2 （319.8 mA·h-g-1） spheres with an outer solid SiO2 layer. In addition, the battery still delivers a high capacity of 403 mA· h· g- 1 at a current density of 1000 mA· g- 1 after 400 cycles. The good electrochemical performance can be attributed to the high surface area （246.7 m2·g- 1 ） and pore volume （0.441 cm3· g-1） of the anode materials, as well as the unique structure of the outer and inner carbon layer which not only enhances electrical conductivity, structural stability, but buffers volume change of the intermediate SiO2 layer during repeated charge-discharge processes. Furthermore, the SiO2 nanoplates with opened macroporous structure facilitate the electrolyte transport and electrochemical reaction.
文摘Experimental research of anode current and anode voltage influence on the speed of decaying plasma resistance change and the time ofthyratron cutoff. Anode current resistance increase is shown to cause thyratron cutoff time increase in case of fixed anode voltage. In turn anode voltage increase in case of fixed anode current causes earlier increase of decaying plasma resistance growth speed and quicker apparatus cutoff：
文摘In the development of rechargeable lithium ion batteries(LIBs),silicon anodes have attracted much attention because of their extremely high theoretical capacity,relatively low Li-insertion voltage and the availability of silicon resources.However,their large volume expansion and fragile solid electrolyte interface(SEI)film hinder their commercial application.To solve these problems,Si has been combined with various carbon materials to increase their structural stability and improve their interface properties.The use of different carbon materials,such as amorphous carbon and graphite,as three-dimensional(3D)protective anode coatings that help buffer mechanical strain and isolate the electrolyte is detailed,and novel methods for applying the coatings are outlined.However,carbon materials used as a protective layer still have some disadvantages,necessitating their modification.Recent developments have focused on modifying the protective carbon shells,and substitutes for the carbon have been suggested.
文摘Currently, many organic materials are being considered as electrode materials and display good electrochemical behavior. However, the most critical issues related to the wide use of organic electrodes are their low thermal stability and poor cycling performance due to their high solubility in electrolytes. Focusing on one of the most conventional carboxylate organic materials, namely lithium terephthalate Li2CsH4O4, we tackle these typical disadvantages via modifying its molecular structure by cation substitution. CaCsH4O4 and A12（C8H4O4）3 are prepared via a facile cation exchange reaction. Of these, CaCsH4O4 presents the best cycling performance with thermal stability up to 570℃ and capacity of 399 mA.h.g-1, without any capacity decay in the voltage window of 0.005-3.0 V. The molecular, crystal structure, and morphology of CaCsH4O4 are retained during cycling. This cation-substitution strategy brings new perspectives in the synthesis of new materials as well as broadening the applications of organic materials in Li/Na-ion batteries.
文摘We report a facile, two-step hydrothermal synthesis of a novel Co304/a-Fe2O3 branched nanowire heterostructure, which can serve as a good candidate for lithium-ion battery anodes with high Li＋ storage capacity and stability. The single-crystalline, primary C0304 nanowire trunk arrays directly grown on Ti substrates allow for efficient electrical and ionic transport. The secondary a-Fe2O3 branches provide enhanced surface area and high theoretical Li＋ storage capacity, and can also serve as volume spacers between neighboring Co3O4 NW arrays to maintain electrolyte penetration as well as reduce the aggregation during Li＋ intercalation, thus leading to improved electrochemical energy storage performance.
基金supported by the National Natural Science Foundation of China(51603013,61574018,and 21606050)the Youth Innovation Promotion Association of Chinese Academy of Sciences(CAS)+1 种基金‘‘Hundred Talents Program"of CASthe National Key Research and Development Program of China(2016YFA0202703)
文摘Red phosphorus has received remarkable attention as a promising anode material for sodium ion batteries(NIBs) due to its high theoretical capacity. However, its practical application has been impeded by its intrinsic low electronic conductivity and large volume variations during sodiation/desodiation process. Here, we design a composite to confine nanosized red phosphorus into the hierarchically porous carbon(HPC) walls by a vaporization-condensation strategy. The mass loading of P in the HPC/P composite is optimized to deliver a reversible specific capacity of 2,202 m Ah/gpbased on the mass of red P(836 m Ah/gcompositebased on the total composite mass), a high capacity retention over 77% after100 cycles, and excellent rate performance of 929 m Ah/gpat 2 C. The hierarchical porous carbon serves as the conductive networks, downsize the red phosphorus to nanoscale, and provide free space to accommodate the large volume expansions. The suppressed mechanical failure of the red phosphorus also enhances the stability of solid-electrolyte interface(SEI) layer, which is confirmed by the microscopy and impedance spectroscopy after the cycling tests. Our studies provide a feasible approach for potentially viable high-capacity NIB anode.
基金supported by the National Natural Science Foundation of China (51672282, 21373238)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA09010101)
文摘Titanium niobium oxides emerge as promising anode materials with potential for applications in lithium ion batteries with high safety and high energy density.However,the innate low electronic conductivity of such a composite oxide seriously limits its practical capacity,which becomes a serious concern especially when a high rate charge/discharge capability is expected.Here,using a modified template-assisted synthesis protocol,which features an in-situ entrapment of both titanium and niobium species during the formation of polymeric microsphere followed by a pyrolysis process,we succeed in preparing hollow microspheres of titanium niobium oxide with high efficiency in structural control.When used as an anode material,the structurally-controlled hollow sample delivers high reversible capacity(103.7 m A h g^(-1)at 50 C)and extraordinary cycling capability especially at high charge/discharge currents(164.7 m A h g^(-1)after 500 cycles at 10 C).
基金supported by the"Strategic Priority Research Program"of the Chinese Academy of Sciences(XDA09010300)the National Natural Science Foundation of China(51225204,91127044,U1301244,21121063)+1 种基金the National Basic Research Program of China(2011CB935700,2012CB932900)the Chinese Academy of Sciences
文摘Lithium-sulfur(Li-S) battery is a promising choice for the next generation of high-energy rechargeable batteries, but its application is impeded by the high dissolution of the polysulfides in commonly used organic electrolyte. Room temperature ionic liquids(RTILs) have been considered as appealing candidates for the electrolytes in Li-S batteries. We investigated the effect of cations in RTILs on the electrochemical performance for Li-S batteries. Ex situ investigation of lithium anode for Li-S batteries indicates that during the discharge/charge process the RTIL with N-methyl-N-propylpyrrolidine cations(P13) can effectively suppress the dissolution of the polysulfides, whereas the RTIL with 1-methyl-3-propyl imidazolium cation(PMIM) barely alleviates the shuttling problem. With 0.5 mol L-1 LiTFSI/P13 TFSI as the electrolyte of Li-S battery, the ketjen black/ sulfur cathode material exhibits high capacity and remarkable cycling stability, which promise the application of the P13-based RTILs in Li-S batteries.
基金WMS acknowledges support under the framework of the INSPIRE programme, funded by the Irish Government＇s Programme for Research in Third Level Institutions, Cycle 4, National Development Plan 2007-2013. COD acknowledges support from Science Foundation Ireland under Award No. 07/SK/ B1232a-STTF11 from the UCC Strategic Research Fund.
文摘This review outlines the developments and recent progress in metal-assisted chemical etching of silicon, summarizing a variety of fundamental and innovative processes and etching methods that form a wide range of nanoscale silicon structures. The use of silicon as an anode for Li-ion batteries is also reviewed, where factors such as film thickness, doping, alloying, and their response to reversible lithiation processes are summarized and discussed with respect to battery cell performance. Recent advances in improving the performance of silicon-based anodes in Li-ion batteries are also discussed. The use of a variety of nanostructured silicon structures formed by many different methods as Li-ion battery anodes is outlined, focusing in particular on the influence of mass loading, core-shell structure, conductive additives, and other parameters. The influence of porosity, dopant type, and doping level on the electrochemical response and cell performance of the silicon anodes are detailed based on recent findings. Perspectives on the future of silicon and related materials, and their compositional and structural modifications for energy storage via several electrochemical mechanisms, are also provided.
基金The financial support from the National Basic Research Program of China(2014CB932300)Natural Science Foundation of Jiangsu Province of China(BK20170630)+1 种基金NSF of China(21633003 and 51602144)sponsored by the JST-CREST ‘‘Phase Interface Science for Highly Efficient Energy Utilization",JST(Japan)
文摘Sodium-ion batteries are promising for large-scale energy storage due to sodium's low cost and infinite abundance. The most popular cathodes for sodium-ion batteries, i.e., the layered sodium-containing oxides, usually exhibit reversible host rearrangement between P-type and O-type stacking upon charge/discharge. Herein we demonstrate that such host rearrangement is unfavorable and can be suppressed by introducing transition-metal ions into sodium layers. The electrode with stabilized P3-type stacking delivers superior rate capability, high energy efficiency, and excellent cycling performance. Owing to the cation-mixing nature, it performs the lowest lattice strain among all reported cathodes for sodium-ion batteries. Our findings highlight the significance of a stable host for sodium-ion storage and moreover underline the fundamental distinction in material design strategy between lithium-and sodium-ion batteries.
