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1.
To improve the microstructural and electrochemical properties of Gadolinium-doped ceria (GDC) electrolytes, materials co-doped ceria with bismuth oxide (1–5 mol%) have been successfully prepared in a one-step sol-gel combustion synthetic route. Sol-gel combustion facilitates molecular mixing of the precursors and substitution of the large Bi3+ cations into the fluorite structure, considerably reducing the sintering temperature. Adding Bi2O3 as a dopant increases the GDC densification to above 99.7% and reduces its traditional sintering temperature by 300 °C. Impedance analyses show that the addition of bismuth enhances the conductivity (3.1?10?2?1.7?10?1 S·cm?1 in the temperature range 600–800 °C) and improves the performance of the solid electrolyte in intermediate-temperature solid oxide fuel cells.  相似文献   

2.
The influence of adding ortho‐phenylenediamine (OPDA) during the polymerization of aniline on the characteristics of the resulting polymer film was examined. When using a platinum electrode, the deposits were obtained from solutions containing 0.1 mol dm?3 aniline and 1, 5, or 10 mmol dm?3 OPDA. The deposits were also prepared from solutions containing 0.5 mol dm?3 aniline and 5, 10, or 50 mmol dm?3 OPDA. In both cases, 3 mol dm?3 phosphoric acid solution was used as a supporting electrolyte. The characteristics of the obtained layers were investigated through the catalytic effect of different polymer layers on hydroquinone/quinone (H2Q/Q) test redox system. The results obtained confirm the earlier established catalytic effect on the potential of the redox reaction by shifting it to more reversible values. However, as the concentration of OPDA was increased, the resulting limiting current decreased, thus indicating in the presence of OPDA a lower population of the available active centers necessary for the catalytic reaction to proceed. The influence of OPDA on polymer characteristics was also studied by using scanning electron microscopy as well as electrochemical impedance spectroscopy. The polymer was synthesized on a stainless steel electrode (13% Cr) from a solution containing 0.5 mol dm?3 aniline and 5, 10, or 50 mmol dm?3 OPDA. The layers were tested in chloride‐containing solutions by monitoring the open circuit potential. The results obtained suggest that, by increasing the concentration of OPDA, the time of OCP in the passive region of stainless steel is prolonged. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

3.
CuInS2 thin films were fabricated by one-step electrochemical deposition from a single alkaline aqueous solution and using conductive glass as the substrate. The electrolyte consisted in 0.01 mol L?1 CuCl2, 0.01 mol L?1 InCl3, 0.5 mol L?1 Na2SO3 and 0.2 mol L?1 Na3C3H5O(COO)3 (CitNa) at pH 8. The films were analyzed using a variety of techniques such as X-ray diffractometry, micro-Raman spectroscopy, X-ray energy dispersive spectroscopy, X-ray photoelectron spectroscopy and photoelectrochemistry. After carrying out a thermal treatment in sulfur vapor, chalcopyrite CuInS2 thin films were obtained. Etching the films in KCN solution was found to be a key step, enabling a final adjustment in the stoichiometry. These thin films exhibited p-type semiconductor behavior with the bandgap of 1.43 eV. The results show that electrodeposition provides a cost-effective and versatile method for the preparation of thin films of CuInS2, even when acidic precursors need to be avoided.  相似文献   

4.
Na3Zr2Si2PO12 (NZSP) solid-state electrolyte is considered one of the most promising solid-state electrolyte because of their excellent electrochemical and thermal stability. Even though, the low conductivity of NZSP solid-state electrolytes hinders practical application. Therefore, an anions/cations co-assisting strategy is proposed by introducing the Zn2+ and F. The influence of adding different amounts of Zn2+ and F on the Na+ conductivity of NZSP was investigated computationally and experimentally. The Zn2+/F co-assisting (Na3.3Zr1.85Zn0.15Si2PO12) solid-state electrolyte exhibits the ionic conductivity of 0.722 mS cm−1 at 30 °C, and the activation energy of ∼0.237 eV. Its applicability in a solid-state battery is tested, and the assembled Na/Na3V2(PO4)3 (NVP) battery exhibits an outstanding electrochemical performance of 98.4% capacity retention after being cycled at 0.5 C. Moreover, DFT calculations also have been used to demonstrate the effect of doping on the crystal structure and space migration energy barrier. This research provides new ideas for improving the electrochemical properties of inorganic solid electrolytes.  相似文献   

5.
New functionalized ILs based on quaternary ammonium cations with three or four ether groups and TFSI anion were synthesized and characterized. Physical and electrochemical properties, including melting point, thermal stability, viscosity, conductivity and electrochemical stability were investigated for these ILs. Five ILs with lower viscosity in these ILs were applied in lithium battery as new electrolytes. Behavior of lithium redox and charge–discharge characteristics of lithium battery were investigated for these IL electrolytes with 0.6 mol kg−1 LiTFSI. Lithium plating and striping on Ni electrode could be observed in these IL electrolytes. Li/LiFePO4 cells using these IL electrolytes without additives had good capacity and cycle property at the current rate of 0.1 C, and the N(2o1)3(2o2)TFSI and N2(2o1)3TFSI electrolytes owned better rate property.  相似文献   

6.
Solvents and electrolytes play an important role in the fabrication of dye‐sensitized solar cells (DSSCs). We have studied the poly(ethylene oxide)‐poly(methyl methacrylate)‐KI‐I2 (PEO‐PMMA‐KI‐I2) polymer blend electrolytes prepared with different wt % of the 2‐mercaptopyridine by solution casting method. The polymer electrolyte films were characterized by the FTIR, X‐ray diffraction, electrochemical impedance and dielectric studies. FTIR spectra revealed complex formation between the PEO‐PMMA‐KI‐I2 and 2‐mercaptopyrindine. Ionic conductivity data revealed that 30% 2‐mercaptopyridine‐doped PEO‐PMMA‐KI‐I2 electrolyte can show higher conductivity (1.55 × 10?5 S cm?1) than the other compositions (20, 40, and 50%). The effect of solvent on the conductivity and dielectric of solid polymer electrolytes was studied for the best composition (30% 2‐mercaptopyridine‐doped PEO‐PMMA‐KI‐I2) electrolyte using various organic solvents such as acetonitrile, N,N‐dimethylformamide, 2‐butanone, chlorobenzene, dimethylsulfoxide, and isopropanol. We found that ac‐conductivity and dielectric constant are higher for the polymer electrolytes processed from N,N‐dimethylformamide. This observation revealed that the conductivity of the solid polymer electrolytes is dependent on the solvent used for processing and the dielectric constant of the film. The photo‐conversion efficiency of dye‐sensitized solar cells fabricated using the optimized polymer electrolytes was 3.0% under an illumination of 100 mW cm?2. The study suggests that N,N‐dimethylformamide is a good solvent for the polymer electrolyte processing due to higher ac‐conductivity beneficial for the electrochemical device applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42489.  相似文献   

7.
A comb‐like polyether, poly(3‐2‐[2‐(2‐methoxyethoxy)ethoxy]ethoxymethyl‐3′‐methyloxetane) (PMEOX), was reacted with hexamethylene diisocyanate and extended with butanediol in a one‐pot procedure to give novel thermoplastic elastomeric poly(ether urethane)s (TPEUs). The corresponding hybrid solid polymer electrolytes were fabricated through doping a mixture of TPEU and poly(vinylidene fluoride) with three kinds of lithium salts, LiClO4, LiBF4 and lithium trifluoromethanesulfonimide (LiTFSI), and were characterized using differential scanning calorimetry, thermogravimetric analysis and Fourier transform infrared spectroscopy. The ionic conductivity of the resulting polymer electrolytes was then assessed by means of AC impedance measurements, which reached 2.1 × 10?4 S cm?1 at 30 °C and 1.7 × 10?3 S cm?1 at 80 °C when LiTFSI was added at a ratio of O:Li = 20. These values can be further increased to 3.5 × 10?4 S cm?1 at 30 °C and 2.2 × 10?3 S cm?1 at 80 °C by introducing nanosized SiO2 particles into the polymer electrolytes. Copyright © 2006 Society of Chemical Industry  相似文献   

8.
Sulphate-based solid electrolytes can have conductivities as high as 3 (Ω cm)?1, as is the case in pure Li2SO4 at a temperature of 800°C. For binary systems highly conducting phases can be found down to at least 415°C. If additional components are added conductivities exceeding 10?3 (Ω cm)?1 can be obtained at room temperature.The conductivity is due to cation mobility and, in contrast to other solid electrolytes such as beta-alumina and AgI-based double salts, both mono- and divalent cations are mobile.Phase diagrams for the systems containing Li2SO4 combined with Na2SO4, K2SO4, Rb2SO4, Cs2SO4, MgSO4, CaSO4, and ZnSO4 have been constructed. A number of galvanic cells using anodes made from Mg, Ca, and Zn have been tested at elevated temperatures. A Mg|Li1.72Mg0.14SO4|MnO2 cell gave an open-circuit voltage of 2.3 V and a power density of 400 W/kg at 745°C. Ag|electrolyte|I2 cells have been tested at room temperature.  相似文献   

9.
To improve the electrochemical properties and enhance the mechanical strength of solid polymer electrolytes, series of composite polymer electrolytes (CPEs) were fabricated with hybrids of thermoplastic polyurethane (TPU) electrospun membrane, polyethylene oxide (PEO), SiO2 nanoparticles and lithium bis(trifluoromethane)sulfonamide (LiTFSI). The structure and properties of the CPEs were confirmed by SEM, XRD, DSC, TGA, electrochemical impedance spectroscopy and linear sweep voltammetry. The TPU electrospun membrane as the skeleton can improve the mechanical properties of the CPEs. In addition, SiO2 particles can suppress the crystallization of PEO. The results show that the TPU‐electrospun‐membrane‐supported PEO electrolyte with 5 wt% SiO2 and 20 wt% LiTFSI (TPU/PEO‐5%SiO2‐20%Li) presents an ionic conductivity of 6.1 × 10?4 S cm?1 at 60 °C with a high tensile strength of 25.6 MPa. The battery using TPU/PEO‐5%SiO2‐20%Li as solid electrolyte and LiFePO4 as cathode shows an attractive discharge capacity of 152, 150, 121, 75, 55 and 26 mA h g?1 at C‐rates of 0.2C, 0.5C, 1C, 2C, 3C and 5C, respectively. The discharge capacity of the cell remains 110 mA h g?1 after 100 cycles at 1C at 60 °C (with a capacity retention of 91%). All the results indicate that this CPE can be applied to all‐solid‐state rechargeable lithium batteries. © 2018 Society of Chemical Industry  相似文献   

10.
The electrochemical behaviour of Au(1 1 1) and highly oriented pyrolytic graphite (HOPG) substrates in the air- and water-stable ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide ([BMP]Tf2N) was investigated using in situ scanning tunneling microscopy (STM). Furthermore, the electrodeposition of Se, In and Cu in the same ionic liquid was investigated. The high thermal stability as well as the large electrochemical window of this ionic liquid compared with aqueous electrolytes allow the direct electrodeposition of grey selenium, indium and copper at variable temperatures, as the first step in making CIS solar cells electrochemically, in a one pot reaction. The results show that grey selenium can be obtained at temperatures ≥100 °C. XRD patterns of the electrodeposit obtained at 100 °C show the characteristic peaks of crystalline grey selenium. Nanocrystalline indium with grain sizes between 100 and 200 nm was formed in the employed ionic liquid, containing 0.1 M InCl3, at room temperature. It was also found that copper(I) species can be introduced into the ionic liquid [BMP]Tf2N by anodic dissolution of a copper electrode and nanocrystalline copper with an average crystallite size of about 50 nm was obtained without additives in the resulting electrolyte.  相似文献   

11.
Lithium solid electrolytes are of major interest for solid-state batteries and electrochemical capacitors (ECs). Currently, the material selection space of liquid electrolytes is dominated by lithium salts paired with organics. Improved safety, as well as the need for higher temperature and high voltage operation, opens up opportunities for glass and ceramic alternatives in these important solid-state energy storage technologies. Lithium thiophosphates in the family x Li2S + (1−x) P2S5 (mol fraction) possess room temperature ionic conductivities greater than 10−3(Ω-cm)-1 in crystallized x = 0.70 (almost the highest in inorganic solid-state electrolytes). Within this review article, we address recent progress made in this class of material. We consider the role of densification on the Li-ion conductivity, as well as our recent data on the effect of densification on the electrochemical properties of the system. We cover the processing techniques of mechanical milling and pressure-forming, discuss microstructure, bulk versus surface conduction, and device integration. The systematic improvement in ionic conductivity with increased density suggests that bulk conduction dominates surface conduction and demonstrates that dense, rather than porous, lithium thiophosphate solid electrolytes are important in the design of solid-state batteries and ECs.  相似文献   

12.
Li7La3Zr2O12-based garnet-type solid electrolytes are promising candidates for use in all-solid-state lithium batteries (ASSLBs). However, their potential in large-scale commercial applications is largely hindered by the time/energy-consuming and lithium-wasting synthetic method which typically needs a long-duration high temperature solid state reaction process. Herein we invent a fast preparation route that involves a short-period thermal reaction (1100 °C for 10 min) in laboratory muffle furnaces following by conventional hot pressing technique to get almost fully dense (Al, Ga, Ta, Nb)-doped garnet-type electrolytes with high phase purity (>99.9 %). The large and compact grains, low porosity and high phase purities of garnet ceramic electrolytes synthesized in this study ensure superior electrochemical performance. Particularly, Ga-doped cubic Li7La3Zr2O12 shows extremely low Ea values (0.17?0.18 eV) and record-high lithium ionic conductivities (>2 × 10?3 S cm-1 at 25 °C).  相似文献   

13.
Removal and recovery of gallium and indium ions in acidic solution with the macroreticular chelating resin containing aminomethylphosphonic acid groups was investigated. The resin (RMT-P) exhibited high affinity for gallium and indium ions in sulfuric acid solution. In the column method, gallium and indium ions in sulfuric acid solution (0.05 or 0.5 mol/dm3) were favorably adsorbed on the RMT-P when the solution containing 27.6 mg/dm3 of gallium ion or 51.4 mg/dm3 of indium ion was passed through the RMT-P column at a space velocity of 15 h?1. The gallium and indium ions adsorbed were eluted by allowing 1 mol/dm3 sodium hydroxide or 4 mol/dm3 hydrochloric acid to pass through the column. The proposed resin appears to be useful for the recovery of gallium and indium ions in sulfuric acid solution.  相似文献   

14.
Osmium hexacyanoferrate films have been prepared using repeated cyclic voltammetry, and the deposition process and the films’ electrocatalytic properties in electrolytes containing various cations have been investigated. The cyclic voltammograms recorded the deposition of osmium hexacyanoferrate films directly from the mixing of Os3+ and Fe(CN)63− ions from solutions containing various cations. An electrochemical quartz crystal microbalance, cyclic voltammetry, and UV-visible spectroscopy were used to study the growth mechanism of the osmium hexacyanoferrate films. The osmium hexacyanoferrate films showed a single redox couple, and the redox reactions included “electron transfer” and “proton transfer” with a formal potential that demonstrates a proton effect in acidic solutions up to a 12 M aqueous HCl solution. The electrochemical and electrochemical quartz crystal microbalance results indicate that the redox process was confined to the immobilized osmium hexacyanoferrate film. The electrocatalytic reduction of dopamine, epinephrine, norepinephrine, S2O32−, and SO52− by the osmium hexacyanoferrate films was performed. The preparation and electrochemical properties of co-deposited osmium(III) hexacyanoferrate and copper(II) hexacyanoferrate films were determined, and their two redox couples showed formal potentials that demonstrated a proton effect and an alkaline cation effect, respectively. Electrocatalytic reactions on the hybrid films were also investigated.  相似文献   

15.
2-(2-methyloxyethoxy)ethanol modified poly (cyclotriphosphazene-co-4,4′-sufonyldiphenol) (PZS) nanotubes were synthesized and solid composite polymer electrolytes based on the surface modified polyphosphazene nanotubes added to PEO/LiClO4 model system were prepared. Differential Scanning Calorimetry (DSC) and Scanning Electron Microscopy (SEM) were used to investigate the characteristics of the composite polymer electrolytes (CPE). The ionic conductivity, lithium ion transference number and electrochemical stability window can be enhanced after the addition of surface modified PZS nanotubes. The electrochemical investigation shows that the solid composite polymer electrolytes incorporated with PZS nanotubes have higher ionic conductivity and lithium ion transference number than the filler SiO2. Maximum ionic conductivity values of 4.95 × 10−5 S cm−1 at ambient temperature and 1.64 × 10−3 S cm−1 at 80 °C with 10 wt % content of surface modified PZS nanotubes were obtained and the lithium ion transference number was 0.41. The good chemical properties of the solid state composite polymer electrolytes suggested that the inorganic-organic hybrid polyphosphazene nanotubes had a promising use as fillers in solid composite polymer electrolytes and the PEO10-LiClO4-PZS nanotubes solid composite polymer electrolyte can be used as a candidate material for lithium polymer batteries.  相似文献   

16.
《Ceramics International》2022,48(9):12142-12151
The performance of sodium superionic conductor (NASICON)-type LiZr2(PO4)3 (LZP) solid electrolytes for Li-ion batteries is dependent on their ion transportation properties. Therefore, to achieve high stability, ionic conductivity, and good compatibility with Li, the LZP solid electrolyte has chosen and doped with Al to improve aforesaid properties. Also, the effect of the dopant on various parameters has been investigated via MD simulations and experimentally. In this study, molecular dynamics (MD) simulations were used to investigate the effect of Al doping on the ion transport properties of Li1+xAlxZr2?x(PO4)3 (LAZP, x = 0.0–1.0) solid electrolytes. A facile solid-state reaction was used to synthesize both pristine and Al-doped solid electrolytes and to estimate the effect of doping on the ionic conductivity and ion diffusion in LZP. Computational and experimental results provided strong evidence of improved ion conductivity and diffusion in LZP owing to the presence of the Al dopant. Furthermore, the computational results agreed well with the experimental results, thereby validating the computational model. A maximum ionic conductivity of σLi = 2.77 × 10?5 S cm ?1 (for x = 0.2) was obtained. Enhanced ionic conductivity was observed with Al dopants owing to the creation of interstitial Li ions through a reduction in grain boundary resistance. However, a further increase in the amount of dopant reduced the ionic conductivity of LZP owing to Li-ion trapping at the most stable and metastable sites around the Al insertions. Doped LZP solid electrolytes are suitable for use in energy storage devices because of their enhanced ionic conductivity compared to that of pristine LZP.  相似文献   

17.
《Ceramics International》2022,48(3):3884-3894
Different kinds of two-dimensional hybrid electrodes have high theoretical capacitance and energy density. However, the origin of the electrochemical storage mechanism still remains elusive in alkaline, acid and neutral electrolytes. Herein, the interstratification-assembled Ti3C2Tx MXene/NiCo-LDHs electrodes were successfully prepared and studied in different electrolytes by in-situ Raman spectroscopy. The results show that H2O molecules in neutral electrolyte combine with –OH at the end of Ti3C2Tx MXene during charging, and debonding occurs during discharge. Similarly, this reaction also occurs in the discharge process with NiCo-LDHs and provides smaller pseudocapacitance characteristics. Although this pseudocapacitance reaction also occurs in acidic and alkaline electrolytes, however, the difference is that the hydrogen ions will promote the electrochemical performance of Ti3C2Tx MXene and has a certain corrosion consumption effect on NiCo-LDHs, but generally improve the electrochemical performance of Ti3C2Tx MXene/NiCo-LDHs. Interestingly, the OH? in alkaline electrolyte can promote the electrochemical performance of NiCo-LDHs, and produce a new electrochemical reaction with –F between the layers of Ti3C2Tx MXene, which greatly improves the overall electrochemical performance of this hybrid electrodes. As a result, Ti3C2Tx MXene/NiCo-LDHs electrodes have the best electrochemical performance in alkaline electrolyte with capacitance of 283 F g?1, energy density of 14.2 Wh kg?1 and power density of 3007.1 W kg?1. This work lays a foundation for the preparation of high-performance two-dimensional hybrid electrochemical energy storage devices.  相似文献   

18.
Nano-Fe2O3 and CoFe2O4 were suspended in molten salt of alkali-metal chloride (LiCl-KCl-CsCl) and their catalytic activity in electrochemical ammonia synthesis was evaluated from potentiostatic electrolysis at 600 K. The presence of nanoparticle suspension in the molten chloride resulted in improved production of NH3, recording NH3 synthesis rate of 1.78×10?10 mol s?1 cm?2 and 3.00×10?10 mol s?1 cm?2 with CoFe2O4 and Fe2O3, which are 102% and 240% higher than that without the use of a nanocatalyst, respectively. We speculated that the nanoparticles triggered both the electrochemical reduction of nitrogen and also chemical reaction between nitrogen and hydrogen that was produced from water electro-reduction on cathode. The use of nanocatalysts in the form of suspension offers an effective way to overcome the sluggish nature of nitrogen reduction in the molten chloride electrolyte.  相似文献   

19.
The behaviour of arsenic, antimony, and bismuth during electrolytic refining of copper has been investigated using cyclic voltammetry, scanning electron microscopy, X-ray diffraction analysis and Auger electron spectroscopy. Electrodeposition was conducted using Group 15 element additions to two different cupric sulfate electrolytes: commercial tank house electrolytes containing 45 g l–1 Cu2+ and 200 g l–1 H2SO4 and liberator cell conditions containing 10 g l–1 Cu2+ and 400 g l–1 H2SO4. Analysis of electrochemical kinetic parameters indicates that the copper cathodes were more active at the higher sulfuric acid concentrations. SEM analysis revealed that Sb and Bi additions promoted truncated copper crystals while As-containing electrolytes produced random crystals. XRD patterns indicated Group 15 elements favour the production of (2 2 0) crystallographic orientation. Surface analyses of the copper deposits using AES techniques show that arsenic and antimony are deposited electrochemically forming primarily solid solution phases with copper in commercial tank house electrolytes. Under liberator cell conditions, a Cu3As intermetallic phase forms when arsenic is present in the electrolyte. Antimony is present in solid solution under these conditions. Reduction of bismuth was not detected during these experiments.  相似文献   

20.
《Ceramics International》2022,48(8):10650-10658
Although doped BaCeO3 electrolytes are proton conductors that undergo the fast conduction processes of inter-mediate temperature solid oxide fuel cells (IT-SOFCs), their wide application is impeded by their poor chemical stability under water vapour or CO2 conditions. In this work, we selected the metallic cations with suitable electronegativity to improve the perovskite crystal structures of BaCeO3 to enhance the chemical stability and electrochemical performance. We utilized Ni and Sm cations to improve the chemical stability of BaCeO3 electrolytes in water vapour and CO2 via a novel synthesis method, and the results revealed that the BaCe0.8Y0.1Ni0.04Sm0.06O3-δ electrolyte, -with high electrochemical performance and chemical stability-, is a promising electrolyte material for conduction in IT-SOFCs. The optimum result offers new insights into synthesizing the membrane of IT-SOFCs for their application.  相似文献   

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