In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to su...In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to supply the desalinated water by mixedbed The electric regeneration technology is a new one used for regeneration of theexhausted ion exchangers in the mixed bed instead of the traditional regeneratingprocess by using acid and abc liquor Electric energy is consumed to regenerat theion exchangers loaded by salts from water treatment without any chemicals- acid alkali. The advantage of the electric regeneration process edibited convenientoperation, no discharge any waste, and therefore no Polluted to the recehang waterbode and the environmental ground展开更多
The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calc...The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calcination temperature and time on the structure and electrochemical properties of the LiNi1/3Co1/3Mn1/3O2 were systemically studied. XRD results revealed that the optimal calcination conditions to prepare the layered LiNi1/3Co1/3Mn1/302 were 950℃ for 15 h. Electrochemical measurement showed that the sample prepared under the such conditions has the highest initial discharge capacity of 160.8 mAh/g and the smallest irreversible capacity loss of 13.5% as well as stable cycling performance at a constant current density of 30 mA/g between 2.5 and 4.3 V versus Li at room temperature.展开更多
SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microsc...SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD patterns presented that the all the as-prepared materials had tetragonal rutile structure but a second phase (Y2O3) was observed when Y content reached 4%. TEM micrograph indicated that Y doped SnO2 had a small particle size ranging from 20 to 25 nm. The electrochemical properties for an anode active material in lithium-ion batteries were investigated at room temperature, including the observed capacity involved in the first-discharge and the reversible capacity values during subsequent charge-discharge cycles. The as-prepared Y-doped SnO2 exhibited promising electrochemical properties as anodes for lithium-ion batteries.展开更多
This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam (FIB) Moire inversion method quantitatively. The curved FIB Moire pattern...This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam (FIB) Moire inversion method quantitatively. The curved FIB Moire patterns indicate that the copper interconnects are a series of curves with continuous variations instead of beelines. The control equation set of the copper interconnects central lines is attained through the Moire inversion method. This work can be extended to inspect the structural defects and provide a reliable support for the interconnects structure fabrication.展开更多
LiNi0.5Mn1.5O4 was synthesized by two different coprecipitation methods:composite carbonate process and composite hydroxide method. The effects of calcination temperature of precursors on the physical properties and e...LiNi0.5Mn1.5O4 was synthesized by two different coprecipitation methods:composite carbonate process and composite hydroxide method. The effects of calcination temperature of precursors on the physical properties and electrochemical performance of the samples were investigated. The results of scanning electron microscopy(SEM) show that as calcination temperature increases,the crystallinity of the samples is improved,and their grain sizes are obviously increased. X-Ray diffraction(XRD) data show that the LiNi0.5Mn1.5O4 compounds obtained by two coprecipitation methods both exhibit a pure cubic spinel structure without any impurities. Furthermore,it is found that the samples prepared with relatively high temperature precursors present large initial discharge capacity(>125 mA·h/g) and excellent cycling stability with a capacity retention rate larger than 91% after 30 cycles at current density of 1 C. This probably derives from their higher crystallinity and larger grain sizes. However,the initial discharge capacity of LiNi0.5Mn1.5O4 synthesized by composite carbonate process is smaller than that prepared by composite carbonate process,but it shows better capacity retention ability.展开更多
Auger Electron Spectroscopy (AES) and Electron Energy Loss Spectroscopy (EELS) have been performed in order to investigate the InP(100) surface subjected to ions bombardment. The InP(100) surface is always contaminate...Auger Electron Spectroscopy (AES) and Electron Energy Loss Spectroscopy (EELS) have been performed in order to investigate the InP(100) surface subjected to ions bombardment. The InP(100) surface is always contaminated by carbon and oxygen revealed by C-KLL and O-KLL AES spectra recorded just after introduction of the sample in the UHV spectrometer chamber. The usually cleaning process of the surface is the bombardment by argon ions. However, even at low energy of ions beam (300 eV) indium clusters and phosphorus vacancies are usually formed on the surface. The aim of our study is to compare the behaviour of the surface when submitted to He+ or H+ ions bombardment. The helium ions accelerated at 500 V voltage and for 45 mn allow removing contaminants but induces damaged and no stoichiometric surface. The proton ions were accelerated at low energy of 500 eV to bombard the InP surface at room temperature. The proton ions broke the In-P chemical bonds to induce the formation of In metal islands. Such a chemical reactivity between hydrogen and phosphorus led to form chemical species such as PH and PH3, which desorbed from the surface. The chemical susceptibly and the small size of H+ advantaged their diffusion into bulk. Since the experimental methods alone were not able to give us with accuracy the disturbed depth of the target by these ions. We associate to the AES and EELS spectroscopies, the TRIM (Transport and Range of Ions in Matter) simulation method in order to show the mechanism of interaction between Ar+, He+ or H+ ions and InP and determine the disturbed depth of the target by argon, helium or proton ions.展开更多
Ion optics are crucial components of ion thrusters and the study of the different ion extraction solutions used since the beginning of the electric propulsion era is essential to understand the evolution of ion engine...Ion optics are crucial components of ion thrusters and the study of the different ion extraction solutions used since the beginning of the electric propulsion era is essential to understand the evolution of ion engines. This work describes ion engine grids' main functions, parameters and issues related to thermal expansion and sputter erosion, and then introduces a review of ion optics used for significant launched and tested ion thrusters since 1970. Configurations, geometries, materials and fabrication methods are analyzed to understand when typical ion thrusters use two or three grids, what are the thicknesses and aperture sizes of the screen, accelerator and decelerator grids, why molybdenum and carbon-based materials such as pyrolytic graphite and carbon–carbon are the best available options for ion optics and what is the manufacturing method for each material.展开更多
Based on NII spectra, some transition probabilities for 2p4f-2p3d and 2s2p23d-2s2p23p are obtained by a semi- classical method. The results are in good agreement with other measurements and the data reported by the Na...Based on NII spectra, some transition probabilities for 2p4f-2p3d and 2s2p23d-2s2p23p are obtained by a semi- classical method. The results are in good agreement with other measurements and the data reported by the National Institute of Standards and Technology. The transition probability for a line of 424.18nm is reported for the first time. Meanwhile, a feasible method of calculating transition parameters related to special excited configurations or highly excited states is provided.展开更多
Phspho-olivine Li Fe PO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources(n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the opti...Phspho-olivine Li Fe PO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources(n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the optimal sample was mixed with glucose and two-step calcinated(500 ℃ and 750 ℃) under high-purity N2 to obtain the Li Fe PO4/C composite. The resultant samples were characterized by X-ray diffraction(XRD), atomic absorption spectrometry(AAS), scanning electron microscops(SEM), transmission electron microscopy(TEM), energy dispersive spectrometry(EDS), elementary analysis(EA) and electrochemical tests. The results show that the optimal reaction condition is to set the reactant concentration at 0.5 mol·L^-1, the reaction temperature at 180 ℃ for 16 h duration. During the reaction course, an intermediate product NH4 Fe PO4·H2O was first synthesized, and then it reacted with Li+ to form Li Fe PO4. The optimized Li Fe PO4 sample with an average particle size(300 to 500 nm) and regular morphology exhibits a relatively high discharge capacity of 84.95 m Ah· g^-1 at the first charge-discharge cycle(0.1C, 1C=170 m A·g^-1). Moreover, the prepared Li Fe PO4/C composite shows a high discharge capacity of 154.3 m Ah·g^-1 at 0.1C and 128.2 m Ah·g^-1 even at 5C. Besides it has good reversibility and stability in CV test.展开更多
A new method for aromatization of Δ^(5(10))-steroidal C_3-dimethyl ketals with pyridinium hydrobromide perbromide (PHP.Py·HBr·Br_2) to aromatic A ring steroids in high yield (90-95%) is described.
Optical absorption,excitation,and fluorescence were investigated in Eu ion-doped CdWO4 single crystal grown by a modified Bridgman method.The results indicate that Eu^2+ and Eu^3+ ions coexist in CdWO4 crystal and a...Optical absorption,excitation,and fluorescence were investigated in Eu ion-doped CdWO4 single crystal grown by a modified Bridgman method.The results indicate that Eu^2+ and Eu^3+ ions coexist in CdWO4 crystal and an energy transfer occurs between these Eu^2+ and Eu^3+ ions.When the crystal is excited by 266-nm light,the energy corresponding to the 4f65d to 8S7/2 transition of Eu^2+ ions results in the excitation of the Eu^3+ ions to the 5DJ level.The effect on fluorescence of annealing in oxygen at various temperatures was investigated.The excitation intensity of Eu^2+ ions at 266 nm decreases as annealing temperature increases from 300 K to 1073 K,but it remains at a certain equilibrium level when the annealing temperature is further increased.展开更多
Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. ...Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. The impacts of different sintering temperatures on the structure and electrochemical performances of Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 were compared by means of X-ray diffractometry(XRD), scanning electron microscopy(SEM), and charge/discharge test as cathode materials for lithium ion batteries. The experimental results show that the spherical morphology of the spray-dried powers maintains during the subsequent heat treatment and the specific capacity increases with rising sintering temperature. When the sintering temperature rises up to 900 ℃ , Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 attains a reversible capacity of 153 mA·h/g between 3.00 and 4.35 V at 0.2C rate with excellent cyclability.展开更多
Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the s...Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the synthesis process. After successive heat treatments at 650 and 950 ℃, the prepared powders were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy, and transmission electron microscopy. The powders prepared by adding salt (NaCl) as grinding aid exhibit a clear R3m layer structure. The powders by other grinding aids like heptane show some impurity peaks in the XRD pattern. The former powders show a uniform particle size distribution of less than 1 μm average size while the latter shows a wide distribution ranging from 1 to 10 μm. Energy dispersive X-ray (EDX) analysiss show that the ratio of Ni, Co, and Mn content in the powder is approximately 1/3, 1/3, and 1/3, respecively. The EDX data indicate no incorporation of sodium or chlorine into the powders. Charge-discharge tests gave an initial discharge capacity of 160 mAh·g-1 for the powders with NaCl addition while 70 mAh·g-1 for the powders with heptane.展开更多
MnO 2 was prepared by column method from normal spinel LiMn 2O 4 with purity of 99.38%.The influence of LiMn 2O 4 grain size and acidity of leaching solution on the lithium leaching process was studied.The result...MnO 2 was prepared by column method from normal spinel LiMn 2O 4 with purity of 99.38%.The influence of LiMn 2O 4 grain size and acidity of leaching solution on the lithium leaching process was studied.The results show that the appropriate range of LiMn 2O 4 grain size was 60-160 meshes and the concentration of leaching solution HCl was 0.1 mol·L -1.The adsorption capacity Q of λ-MnO 2 for lithium increased with the increase of pH and changed markedly at pH 6.0-10.0.It was 3.80mmol/g at pH 12.0.The distribution coefficients K d of Li + and Na + were 3.406×10 4 and 2.300 respectively,and the separation coefficient α Li Na was 1.481×10 4 at pH 6.5.As a result,λ-MnO 2 is a high performance ion-sieve material for lithium ion.展开更多
The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathologi...The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathological feature,how to detect it is an important affair.In this paper,we measure the concentration of sodium ions by the extended gate field effect transistor (EGFET).We use three different substrates RuO_x/p-Si,ITO glass,SnO_2/ITO to fabricate EGFET,and we choose the optimum structure.The fabrication of device needed to use the entrapment method.展开更多
In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained a...In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained an amorphous state up to 500.The activation energy was calculated to be 252 kJ/mol according to the modified Kissinger equation.展开更多
文摘In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to supply the desalinated water by mixedbed The electric regeneration technology is a new one used for regeneration of theexhausted ion exchangers in the mixed bed instead of the traditional regeneratingprocess by using acid and abc liquor Electric energy is consumed to regenerat theion exchangers loaded by salts from water treatment without any chemicals- acid alkali. The advantage of the electric regeneration process edibited convenientoperation, no discharge any waste, and therefore no Polluted to the recehang waterbode and the environmental ground
基金financially supported by the Natural Science Foundation of Guangxi Province, China (No. GKZ0832256)
文摘The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calcination temperature and time on the structure and electrochemical properties of the LiNi1/3Co1/3Mn1/3O2 were systemically studied. XRD results revealed that the optimal calcination conditions to prepare the layered LiNi1/3Co1/3Mn1/302 were 950℃ for 15 h. Electrochemical measurement showed that the sample prepared under the such conditions has the highest initial discharge capacity of 160.8 mAh/g and the smallest irreversible capacity loss of 13.5% as well as stable cycling performance at a constant current density of 30 mA/g between 2.5 and 4.3 V versus Li at room temperature.
基金NSFC (20471055)Henan Outstanding Youth Science Fund (0612002700)
文摘SnO2 doped with Y were prepared by co-precipitation method and tested in lithium-ion cells. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD patterns presented that the all the as-prepared materials had tetragonal rutile structure but a second phase (Y2O3) was observed when Y content reached 4%. TEM micrograph indicated that Y doped SnO2 had a small particle size ranging from 20 to 25 nm. The electrochemical properties for an anode active material in lithium-ion batteries were investigated at room temperature, including the observed capacity involved in the first-discharge and the reversible capacity values during subsequent charge-discharge cycles. The as-prepared Y-doped SnO2 exhibited promising electrochemical properties as anodes for lithium-ion batteries.
基金supported by the JSPS Postdoctoral Fellowship for Foreign Researchersthe National Basic Research Program of China ("973" Project) (2010CB631005,2011CB606105)+1 种基金the National Natural Science Foundation of China (11172151,90916010)Specialized Research Fund for the Doctoral Program of Higher Education(20090002110048)
文摘This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam (FIB) Moire inversion method quantitatively. The curved FIB Moire patterns indicate that the copper interconnects are a series of curves with continuous variations instead of beelines. The control equation set of the copper interconnects central lines is attained through the Moire inversion method. This work can be extended to inspect the structural defects and provide a reliable support for the interconnects structure fabrication.
基金Project(2007CB613607) supported by the National Basic Research Program of China
文摘LiNi0.5Mn1.5O4 was synthesized by two different coprecipitation methods:composite carbonate process and composite hydroxide method. The effects of calcination temperature of precursors on the physical properties and electrochemical performance of the samples were investigated. The results of scanning electron microscopy(SEM) show that as calcination temperature increases,the crystallinity of the samples is improved,and their grain sizes are obviously increased. X-Ray diffraction(XRD) data show that the LiNi0.5Mn1.5O4 compounds obtained by two coprecipitation methods both exhibit a pure cubic spinel structure without any impurities. Furthermore,it is found that the samples prepared with relatively high temperature precursors present large initial discharge capacity(>125 mA·h/g) and excellent cycling stability with a capacity retention rate larger than 91% after 30 cycles at current density of 1 C. This probably derives from their higher crystallinity and larger grain sizes. However,the initial discharge capacity of LiNi0.5Mn1.5O4 synthesized by composite carbonate process is smaller than that prepared by composite carbonate process,but it shows better capacity retention ability.
文摘Auger Electron Spectroscopy (AES) and Electron Energy Loss Spectroscopy (EELS) have been performed in order to investigate the InP(100) surface subjected to ions bombardment. The InP(100) surface is always contaminated by carbon and oxygen revealed by C-KLL and O-KLL AES spectra recorded just after introduction of the sample in the UHV spectrometer chamber. The usually cleaning process of the surface is the bombardment by argon ions. However, even at low energy of ions beam (300 eV) indium clusters and phosphorus vacancies are usually formed on the surface. The aim of our study is to compare the behaviour of the surface when submitted to He+ or H+ ions bombardment. The helium ions accelerated at 500 V voltage and for 45 mn allow removing contaminants but induces damaged and no stoichiometric surface. The proton ions were accelerated at low energy of 500 eV to bombard the InP surface at room temperature. The proton ions broke the In-P chemical bonds to induce the formation of In metal islands. Such a chemical reactivity between hydrogen and phosphorus led to form chemical species such as PH and PH3, which desorbed from the surface. The chemical susceptibly and the small size of H+ advantaged their diffusion into bulk. Since the experimental methods alone were not able to give us with accuracy the disturbed depth of the target by these ions. We associate to the AES and EELS spectroscopies, the TRIM (Transport and Range of Ions in Matter) simulation method in order to show the mechanism of interaction between Ar+, He+ or H+ ions and InP and determine the disturbed depth of the target by argon, helium or proton ions.
文摘Ion optics are crucial components of ion thrusters and the study of the different ion extraction solutions used since the beginning of the electric propulsion era is essential to understand the evolution of ion engines. This work describes ion engine grids' main functions, parameters and issues related to thermal expansion and sputter erosion, and then introduces a review of ion optics used for significant launched and tested ion thrusters since 1970. Configurations, geometries, materials and fabrication methods are analyzed to understand when typical ion thrusters use two or three grids, what are the thicknesses and aperture sizes of the screen, accelerator and decelerator grids, why molybdenum and carbon-based materials such as pyrolytic graphite and carbon–carbon are the best available options for ion optics and what is the manufacturing method for each material.
基金Project supported by the National Natural Science Foundation of China (Grant No 40475007).
文摘Based on NII spectra, some transition probabilities for 2p4f-2p3d and 2s2p23d-2s2p23p are obtained by a semi- classical method. The results are in good agreement with other measurements and the data reported by the National Institute of Standards and Technology. The transition probability for a line of 424.18nm is reported for the first time. Meanwhile, a feasible method of calculating transition parameters related to special excited configurations or highly excited states is provided.
基金Funded by the National Natural Science Foundation of China(No.51004074)
文摘Phspho-olivine Li Fe PO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources(n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the optimal sample was mixed with glucose and two-step calcinated(500 ℃ and 750 ℃) under high-purity N2 to obtain the Li Fe PO4/C composite. The resultant samples were characterized by X-ray diffraction(XRD), atomic absorption spectrometry(AAS), scanning electron microscops(SEM), transmission electron microscopy(TEM), energy dispersive spectrometry(EDS), elementary analysis(EA) and electrochemical tests. The results show that the optimal reaction condition is to set the reactant concentration at 0.5 mol·L^-1, the reaction temperature at 180 ℃ for 16 h duration. During the reaction course, an intermediate product NH4 Fe PO4·H2O was first synthesized, and then it reacted with Li+ to form Li Fe PO4. The optimized Li Fe PO4 sample with an average particle size(300 to 500 nm) and regular morphology exhibits a relatively high discharge capacity of 84.95 m Ah· g^-1 at the first charge-discharge cycle(0.1C, 1C=170 m A·g^-1). Moreover, the prepared Li Fe PO4/C composite shows a high discharge capacity of 154.3 m Ah·g^-1 at 0.1C and 128.2 m Ah·g^-1 even at 5C. Besides it has good reversibility and stability in CV test.
文摘A new method for aromatization of Δ^(5(10))-steroidal C_3-dimethyl ketals with pyridinium hydrobromide perbromide (PHP.Py·HBr·Br_2) to aromatic A ring steroids in high yield (90-95%) is described.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 50972061,51272109,and 21171102)the Natural Science Foundation of Zhejiang Province of China (Grant Nos. R4100364 and Z4110072)+1 种基金the Natural Science Foundation of Ningbo City (Grant No. 2012A610115)K. C.Wong Magna Fund in Ningbo University
文摘Optical absorption,excitation,and fluorescence were investigated in Eu ion-doped CdWO4 single crystal grown by a modified Bridgman method.The results indicate that Eu^2+ and Eu^3+ ions coexist in CdWO4 crystal and an energy transfer occurs between these Eu^2+ and Eu^3+ ions.When the crystal is excited by 266-nm light,the energy corresponding to the 4f65d to 8S7/2 transition of Eu^2+ ions results in the excitation of the Eu^3+ ions to the 5DJ level.The effect on fluorescence of annealing in oxygen at various temperatures was investigated.The excitation intensity of Eu^2+ ions at 266 nm decreases as annealing temperature increases from 300 K to 1073 K,but it remains at a certain equilibrium level when the annealing temperature is further increased.
文摘Spherical Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 was prepared via the homogenous precursors produced by solution spray-drying method. The precursors were sintered at different temperatures between 600 and 1 000 ℃ for 10 h. The impacts of different sintering temperatures on the structure and electrochemical performances of Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 were compared by means of X-ray diffractometry(XRD), scanning electron microscopy(SEM), and charge/discharge test as cathode materials for lithium ion batteries. The experimental results show that the spherical morphology of the spray-dried powers maintains during the subsequent heat treatment and the specific capacity increases with rising sintering temperature. When the sintering temperature rises up to 900 ℃ , Li(Ni_(1/3)Mn_(1/3)Co_(1/3))O_2 attains a reversible capacity of 153 mA·h/g between 3.00 and 4.35 V at 0.2C rate with excellent cyclability.
基金This research was supportedby a grant under‘Development of Key Materials and Fundamental Tech-nology for Secondary Battery’Program of the Ministry of Commerce,Industry and Energy,Korea.
文摘Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the synthesis process. After successive heat treatments at 650 and 950 ℃, the prepared powders were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy, and transmission electron microscopy. The powders prepared by adding salt (NaCl) as grinding aid exhibit a clear R3m layer structure. The powders by other grinding aids like heptane show some impurity peaks in the XRD pattern. The former powders show a uniform particle size distribution of less than 1 μm average size while the latter shows a wide distribution ranging from 1 to 10 μm. Energy dispersive X-ray (EDX) analysiss show that the ratio of Ni, Co, and Mn content in the powder is approximately 1/3, 1/3, and 1/3, respecively. The EDX data indicate no incorporation of sodium or chlorine into the powders. Charge-discharge tests gave an initial discharge capacity of 160 mAh·g-1 for the powders with NaCl addition while 70 mAh·g-1 for the powders with heptane.
基金theNationalNaturalScienceFoundationofChi na (No .5 9972 0 2 7)theNaturalScienceFoundationofHubeiProvince (No .2 0 0 2AB0 74) )
文摘MnO 2 was prepared by column method from normal spinel LiMn 2O 4 with purity of 99.38%.The influence of LiMn 2O 4 grain size and acidity of leaching solution on the lithium leaching process was studied.The results show that the appropriate range of LiMn 2O 4 grain size was 60-160 meshes and the concentration of leaching solution HCl was 0.1 mol·L -1.The adsorption capacity Q of λ-MnO 2 for lithium increased with the increase of pH and changed markedly at pH 6.0-10.0.It was 3.80mmol/g at pH 12.0.The distribution coefficients K d of Li + and Na + were 3.406×10 4 and 2.300 respectively,and the separation coefficient α Li Na was 1.481×10 4 at pH 6.5.As a result,λ-MnO 2 is a high performance ion-sieve material for lithium ion.
文摘The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathological feature,how to detect it is an important affair.In this paper,we measure the concentration of sodium ions by the extended gate field effect transistor (EGFET).We use three different substrates RuO_x/p-Si,ITO glass,SnO_2/ITO to fabricate EGFET,and we choose the optimum structure.The fabrication of device needed to use the entrapment method.
文摘In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained an amorphous state up to 500.The activation energy was calculated to be 252 kJ/mol according to the modified Kissinger equation.