The authors reported a facile method for the synthesis of manganese dioxide without any template and catalyst at a low-temperature. The prepared sample was characterized with X-ray diffraction（XRD）, scanning electro...The authors reported a facile method for the synthesis of manganese dioxide without any template and catalyst at a low-temperature. The prepared sample was characterized with X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Brunauer-Emmett-Teller（BET） surface analysis, Fourier transform infrared（FTIR） spectrometry, cyclic voltammetry, alternative current（AC） impedance test and battery discharge test. It is found that the prepared sample belongs to α-MnO2 and has a microsphere morphology and a large BET surface area. The electrochemical characterization indicates that the prepared sample displays a larger electrochemical capacitance than the commercial electrolytic manganese dioxides（EMD） in Na2SO4 solution, and exhibits larger discharge capacity than EMD, especially at a high rate discharge condition when it is used as cathode of alkaline Zn/MnO2 battery.展开更多
This work studies the optimum reductive leaching process for manganese and zinc recovery from spent alkaline battery paste. The effects of reducing agents, acid concentration, pulp density, reaction temperature, and l...This work studies the optimum reductive leaching process for manganese and zinc recovery from spent alkaline battery paste. The effects of reducing agents, acid concentration, pulp density, reaction temperature, and leaching time on the dissolution of manganese and zinc were investigated in detail. Manganese dissolution by reductive acidic media is an intermediate-controlled process with an activation energy of 12.28 kJ＇mo1-1. After being leached, manganese and zinc were selectively precipitated with sodium hydroxide. The zinc was entirely con- verted into zincate （Zn（OH）42-） ions and thus did not co-precipitate with manganese hydroxide during this treatment （2.0 M NaOH, 90 min, 200 r/rain, pH 〉 13）. After the manganese was removed from the solution, the Zn（OH）4^2- was precipitated as zinc sulfate in the presence of sulfuric acid. The results indicated that this process could be effective in recovering manganese and zinc from alkaline batteries.展开更多
Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of...Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.展开更多
Grainy electrolytic manganese dioxide was prepared by electrodeposition in a 0.9 mol/L MnSO4 and 2.5 mol/LH2SO4 solution. The structure, particle size and appearance of the grainy electrolytic manganese dioxide were d...Grainy electrolytic manganese dioxide was prepared by electrodeposition in a 0.9 mol/L MnSO4 and 2.5 mol/LH2SO4 solution. The structure, particle size and appearance of the grainy electrolytic manganese dioxide were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrographs measurements. Current density has important effects on cell voltage, anodic current efficiency and particle size of the grainy electrolytic manganese dioxide, and the optimum current density is 30 A/dm2. The grainy electrolytic manganese dioxide electrodeposited under the optimum conditions consists of γ-MnO2 with an orthorhombic lattice structure; the grainy electrolytic manganese dioxide has a spherical or sphere-like appearance and a narrow particle size distribution with an average particle diameter of 7.237 μm.展开更多
The effects of temperature and the concentration of sulfuric acid on the cell voltage, the anode current efficiency of electrodeposition and the particle size of grainy electrolytic manganese dioxide （EMD） were inve...The effects of temperature and the concentration of sulfuric acid on the cell voltage, the anode current efficiency of electrodeposition and the particle size of grainy electrolytic manganese dioxide （EMD） were investigated. The structure, particle size and appearance of grainy EMD were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrograph measurements. As the concentration of sulfuric acid increases, both the cell voltage and the average anode current efficiency decrease. With the increase of electrolysis temperature in the range of 30-60℃, the cell voltage, average anode current efficiency and particle size decrease. The optimum temperature of 30℃ and concentration of sulfuric acid of 2.5 mol/L for electrodeposition of the grainy EMD were obtained. XRD patterns show that the grainy EMD electrodeposited under the optimum conditions consists of γ-MnO2 and has an orthorhombic lattice structure. According to the results of SEM, the grainy EMD has a spherical or sphere-like appearance and a narrow particle size distribution with an average size of about 7μm. The grainy EMD is a promising cathode of rechargeable alkaline batteries for high energy density and a prospective precursor for production of the LiMn2O4 cathode of lithium ion batteries.展开更多
In this study electrochemical performance of Al and some of its alloys （Al-Zn, Al-rvlg and Al-rvln） anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the b...In this study electrochemical performance of Al and some of its alloys （Al-Zn, Al-rvlg and Al-rvln） anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn〉Al-Mg〉Al〉Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy （SEM）. SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure. Electrolytic manganese dioxide （EMD） produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore （β-MnO2） by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample （EMD1） was performed well in comparison with EMD standard （EMD2） （commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S）. SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.展开更多
基金Supported by the National Natural Science Foundation of China(No.20873046)the Specialized Research Fund for the Doctoral Program of Higher Education of China(No.200805740004)+1 种基金the Natural Science Foundation of Guangdong Province,China(No.10351063101000001)the Fund of Guangdong Province Cooperation of Producing, Studying and Researching,China (No.2011B090400317)
文摘The authors reported a facile method for the synthesis of manganese dioxide without any template and catalyst at a low-temperature. The prepared sample was characterized with X-ray diffraction（XRD）, scanning electron microscopy（SEM）, Brunauer-Emmett-Teller（BET） surface analysis, Fourier transform infrared（FTIR） spectrometry, cyclic voltammetry, alternative current（AC） impedance test and battery discharge test. It is found that the prepared sample belongs to α-MnO2 and has a microsphere morphology and a large BET surface area. The electrochemical characterization indicates that the prepared sample displays a larger electrochemical capacitance than the commercial electrolytic manganese dioxides（EMD） in Na2SO4 solution, and exhibits larger discharge capacity than EMD, especially at a high rate discharge condition when it is used as cathode of alkaline Zn/MnO2 battery.
基金Scientific and Technological Research Council of Turkey for financial support
文摘This work studies the optimum reductive leaching process for manganese and zinc recovery from spent alkaline battery paste. The effects of reducing agents, acid concentration, pulp density, reaction temperature, and leaching time on the dissolution of manganese and zinc were investigated in detail. Manganese dissolution by reductive acidic media is an intermediate-controlled process with an activation energy of 12.28 kJ＇mo1-1. After being leached, manganese and zinc were selectively precipitated with sodium hydroxide. The zinc was entirely con- verted into zincate （Zn（OH）42-） ions and thus did not co-precipitate with manganese hydroxide during this treatment （2.0 M NaOH, 90 min, 200 r/rain, pH 〉 13）. After the manganese was removed from the solution, the Zn（OH）4^2- was precipitated as zinc sulfate in the presence of sulfuric acid. The results indicated that this process could be effective in recovering manganese and zinc from alkaline batteries.
基金supported by Fund of National Key Laboratory of Science and Technology on Advanced Composites in Special Environments(Grant No.6142905192507)Shenzhen Science and Technology Plan Supported Project(Grant No.JCYJ20170413105844696)+1 种基金China Scholarship Council(Grant No.201606125092)Singapore Ministry of Education Academic Research Fund Tier 2(MOE2018-T2-2-178)
文摘Aqueous alkaline battery represents a promising energy storage technology with both high energy density and high power density as rechargeable batteries.However,the low theoretical capacities,kinetics and stability of anode materials have limited their developments and commercializations.In this study,we propose a novel method to produce two-dimensional layered bismuth oxide selenium(Bi_(2)O_(2)Se)and reduced graphene oxide(r GO)composites via a one-step hydrothermal method.The volume change caused by phase change during rapid charging and discharging is significantly reduced and the capacity reaches 263.83 m Ah g^(-1)at a current density of 0.5 A g^(-1).The Bi_(2)O_(2)Se/r GO electrode exhibits excellent cycling stability in which the capacity retention rate is 81.04%after 5000 cycles.More importantly,the Bi_(2)O_(2)Se/r GO nanosheet composite is used as the anode electrode material with MnCo_(2)O_(4.5)@Ni(OH)_(2)as the cathode electrode material in aqueous alkaline battery.When the energy density is 76.16 W h kg^(-1),the power density reaches 308.65 W kg^(-1).At a power density of 10.21 k W kg^(-1),the energy density remains as high as 33.86 W h kg^(-1).The results presented here may advance the understanding of the issues facing the development of aqueous battery anode materials.
文摘Grainy electrolytic manganese dioxide was prepared by electrodeposition in a 0.9 mol/L MnSO4 and 2.5 mol/LH2SO4 solution. The structure, particle size and appearance of the grainy electrolytic manganese dioxide were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrographs measurements. Current density has important effects on cell voltage, anodic current efficiency and particle size of the grainy electrolytic manganese dioxide, and the optimum current density is 30 A/dm2. The grainy electrolytic manganese dioxide electrodeposited under the optimum conditions consists of γ-MnO2 with an orthorhombic lattice structure; the grainy electrolytic manganese dioxide has a spherical or sphere-like appearance and a narrow particle size distribution with an average particle diameter of 7.237 μm.
基金This work was financially supported by the National Natural Science Foundation of China (No. 50302016) and the PostdoctoralScience Foundation of Central South University.
文摘The effects of temperature and the concentration of sulfuric acid on the cell voltage, the anode current efficiency of electrodeposition and the particle size of grainy electrolytic manganese dioxide （EMD） were investigated. The structure, particle size and appearance of grainy EMD were determined by powder X-ray diffraction, laser particle size analysis and scanning electron micrograph measurements. As the concentration of sulfuric acid increases, both the cell voltage and the average anode current efficiency decrease. With the increase of electrolysis temperature in the range of 30-60℃, the cell voltage, average anode current efficiency and particle size decrease. The optimum temperature of 30℃ and concentration of sulfuric acid of 2.5 mol/L for electrodeposition of the grainy EMD were obtained. XRD patterns show that the grainy EMD electrodeposited under the optimum conditions consists of γ-MnO2 and has an orthorhombic lattice structure. According to the results of SEM, the grainy EMD has a spherical or sphere-like appearance and a narrow particle size distribution with an average size of about 7μm. The grainy EMD is a promising cathode of rechargeable alkaline batteries for high energy density and a prospective precursor for production of the LiMn2O4 cathode of lithium ion batteries.
文摘In this study electrochemical performance of Al and some of its alloys （Al-Zn, Al-rvlg and Al-rvln） anodes vs MnO2 cathode were carried out in alkaline solution. The results show that the Al-Zn alloy anode has the best cell capacity among the other alloys. Cell capacity values go in the order Al-Zn〉Al-Mg〉Al〉Al-Mn. This result is probably related to the nature of passive films formed on the surface of the alloys which examined by scanning electron microscopy （SEM）. SEM morphologies of Al and its alloys showed coarse grains of passive films formed on the surface of these anode materials while Al-Mn morphology shows a needle-like structure. Electrolytic manganese dioxide （EMD） produced by electrodepositing on platinum anode from liquor resulting from reduction of low grade pyrolusite ore （β-MnO2） by sulfur slag was characterized as cathode in alkaline Zn-MnO2 batteries. Ore produced sample （EMD1） was performed well in comparison with EMD standard （EMD2） （commercial battery grade electrolytic manganese dioxide, TOSOH-Hellas GH-S）. SEM morphology of Zn anode after cell reaction was carried out and showed that Zn anode has fine grains of passive film on its surface.
