CN108046320B - Preparation method of supercapacitor electrode material vanadium sulfide nanoflower - Google Patents
Preparation method of supercapacitor electrode material vanadium sulfide nanoflower Download PDFInfo
- Publication number
- CN108046320B CN108046320B CN201711377254.5A CN201711377254A CN108046320B CN 108046320 B CN108046320 B CN 108046320B CN 201711377254 A CN201711377254 A CN 201711377254A CN 108046320 B CN108046320 B CN 108046320B
- Authority
- CN
- China
- Prior art keywords
- vanadium sulfide
- nanoflower
- dodecahydrate
- electrode material
- sodium orthovanadate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G31/00—Compounds of vanadium
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
- H01G11/22—Electrodes
- H01G11/24—Electrodes characterised by structural features of the materials making up or comprised in the electrodes, e.g. form, surface area or porosity; characterised by the structural features of powders or particles used therefor
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01G—CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES OR LIGHT-SENSITIVE DEVICES, OF THE ELECTROLYTIC TYPE
- H01G11/00—Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
- H01G11/22—Electrodes
- H01G11/30—Electrodes characterised by their material
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/30—Particle morphology extending in three dimensions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/13—Energy storage using capacitors
Abstract
The invention discloses a preparation method of a supercapacitor electrode material vanadium sulfide nanoflower, which comprises the following steps: (1) preparing sodium orthovanadate dodecahydrate and thioacetamide into a precursor solution, wherein the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is 1: 1.2-3.5, and the mass concentration of the sodium orthovanadate dodecahydrate is 0.02-0.05 g/mL; (2) and carrying out hydrothermal reaction on the precursor solution, and washing and drying a product after the reaction is finished to obtain the vanadium sulfide nanoflower. The vanadium sulfide nanoflower prepared by the method is of a three-dimensional structure, stacking of flaky vanadium sulfide is well avoided, the specific surface area of the vanadium sulfide is improved, the vanadium sulfide nanoflower can be used as an electrode material of a super capacitor, higher specific capacity can be obtained, the cycle service life is prolonged, and the vanadium sulfide nanoflower has high energy density and power density, and the maximum specific capacity of the vanadium sulfide nanoflower prepared by the method can reach 500.4F g‑1The specific capacity is still as high as 459.4F g after 500 cycles‑1The capacity retention was 91.9%.
Description
Technical Field
The invention belongs to the field of electrode materials, and particularly relates to a preparation method of a supercapacitor electrode material vanadium sulfide nanoflower.
Background
As a new energy storage device, the super capacitor has the advantages of long service life, high energy density and the like, and has attracted great research interest. The active electrode material of the super capacitor influences the electrochemical performance of the energy storage device to a great extent, so that the search for an electrode material with a novel structure becomes the key of the development of the super capacitor. The micro-nano material with the three-dimensional hierarchical structure has important research significance due to the unique structure and physical and chemical properties, and particularly, the synthesis of the layered transition metal sulfide micro-nano structure and the research of the photoelectric properties are widely concerned by people.
The vanadium disulfide has a unique layered structure, is beneficial to the adsorption and the desorption of ions, can be embedded with metal ions such as Li and the like with different proportions to form an intercalation compound, and has the property of pseudo capacitance along with the transfer of electrons in the intercalation and the deintercalation processes. Due to the unique property of the vanadium disulfide, the vanadium disulfide has good application prospects in the electrochemical field, such as the fields of lithium ion or sodium ion battery electrode materials, super capacitor electrode materials and the like.
The existing method for synthesizing vanadium disulfide mainly comprises a solid phase method and a hydrothermal method, wherein the solid phase method has the defects of high energy consumption, low efficiency, insufficiently fine powder, easiness in impurity mixing and the like, and the hydrothermal method is widely used for synthesizing vanadium disulfide due to the advantages of simplicity and convenience in operation, low energy consumption and small pollution. However, the existing vanadium disulfide synthesized by a hydrothermal method is a nanosheet with a two-dimensional structure, and the scattered nanosheets are easy to stack or superpose when in use, so that the available specific surface area is greatly reduced, the specific capacity of the vanadium disulfide as a supercapacitor electrode material is further greatly reduced, and the cycle life is poor.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a preparation method of a supercapacitor electrode material vanadium sulfide nanoflower, and solves the problems of low specific capacity and poor cycle life of vanadium sulfide as a capacitor material.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a supercapacitor electrode material vanadium sulfide nanoflower comprises the following steps:
(1) dissolving sodium orthovanadate dodecahydrate and thioacetamide in water to prepare a precursor solution, wherein the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is 1: 1.2-3.5, and the mass concentration of the sodium orthovanadate dodecahydrate is 0.02-0.05 g/mL;
(2) and carrying out hydrothermal reaction on the precursor solution, and washing and drying a product after the reaction is finished to obtain the vanadium sulfide nanoflower.
In the invention, thioacetamide is used as a reducing agent and is used for hydrothermal treatmentThe vanadium with the valence of +5 is reduced to the vanadium with the valence of +4 in the reaction, and simultaneously the vanadium serves as a sulfur source, and hydrogen sulfide generated by the decomposition of the vanadium reacts with V in water4+And combining to generate precipitate to finally obtain the nanometer flower-shaped vanadium sulfide. The mass ratio and the concentration of sodium orthovanadate dodecahydrate to thioacetamide have great influence on the appearance of the prepared vanadium sulfide, and the prepared vanadium sulfide can have a three-dimensional structure in a nano flower shape only by controlling the mass ratio and the mass concentration of the sodium orthovanadate dodecahydrate to thioacetamide. If the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is smaller, the obtained product is less, and if the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is larger, the obtained vanadium sulfide nanoflowers are less in number and more in impurities; if the mass concentration of the sodium orthovanadate dodecahydrate is smaller, the vanadium sulfide is in a microsphere shape, nano flowers are not generated, and if the mass concentration of the sodium orthovanadate dodecahydrate is larger, vanadium sulfide crystals excessively grow to form nano sheets. The sodium orthovanadate dodecahydrate used in the invention can avoid weighing errors caused by water absorption because crystal water is contained, and in actual use, the sodium orthovanadate can be directly used within an effective weighing range, and the mass of the sodium orthovanadate can be converted according to the mass of the sodium orthovanadate dodecahydrate.
Preferably, the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is 1: 2-3. Under the mass ratio, the vanadium sulfide is more favorable for forming a nano flower shape.
Preferably, the mass concentration of the sodium orthovanadate dodecahydrate is 0.03-0.04 g/mL. At this concentration, the vanadium sulfide is more favorable to form a nano flower shape.
Preferably, in the step (1), sodium orthovanadate dodecahydrate and thioacetamide are dissolved in water, and the solution is stirred for 30-60 min to obtain the precursor solution. Stirring is beneficial to dissolving thioacetamide and ammonium orthovanadate dodecahydrate, the stirring time is short, thioacetamide cannot be completely dissolved, and the thioacetamide dissolved in water is excessively decomposed after the stirring time is too long.
Preferably, the mixed solution of sodium orthovanadate dodecahydrate and thioacetamide is stirred at 20-30 ℃.
Preferably, the hydrothermal reaction temperature is 130-160 ℃, and the reaction time is 22-26 h. Different reaction temperatures can affect the morphology of the prepared vanadium sulfide, the temperature is too low, nano flowers are not generated, and nano sheets can appear when the temperature is too high.
Preferably, the product in step (2) is washed with deionized water and ethanol, respectively. The purpose of the washing is mainly to remove impurities possibly present in the product, and deionized water and ethanol can be used to wash 3 times each.
Preferably, the product in the step (2) is dried in vacuum at 60-100 ℃. The vacuum drying can prevent the material from being oxidized and can also avoid the change of the appearance of the sample caused by overhigh drying temperature.
The vanadium sulfide nanoflower prepared by the method is applied to preparing a supercapacitor electrode material, and has high specific capacity and long cycle life.
The vanadium sulfide nanoflower prepared by the method can also be applied to preparation of lithium ion batteries or sodium ion batteries.
Compared with the prior art, the invention has the following beneficial effects:
1. according to the method, the vanadium sulfide nanoflower with the three-dimensional structure is successfully prepared by controlling the mass ratio and the concentration of sodium orthovanadate dodecahydrate and thioacetamide, and compared with the flaky vanadium sulfide prepared by the existing method, the vanadium sulfide nanoflower prepared by the method well avoids the stacking of the flaky vanadium sulfide, improves the specific surface area of the vanadium sulfide, can obtain higher specific capacity when used as an electrode material of a super capacitor, also prolongs the cycle service life, and has high energy density and power density.
2. VS prepared by the invention2Nanoflower with current density of 1A g-1Specific capacity at 554.8F g-1While the current density was 1A g-1The power density is 450W kg-1The energy density was 62.4 Wh kg-1Current density of 2 Ag-1The capacity retention rate is 91.9 percent after the time of 500 cycles, and the current density is increased to 5A g-1The specific capacity is 367.2F g-1The specific capacity retention rate reaches 66.2 percent, and the nano-silver powder still has very high specific capacity under high current density,is a super capacitor electrode material with excellent performance.
Drawings
FIG. 1 is an XRD analysis of vanadium sulfide nanoflowers prepared in example 1;
FIG. 2 is a TEM image of vanadium sulfide nanoflowers prepared in example 1;
FIG. 3 is a scanning electron micrograph of vanadium sulfide nanoflowers prepared in example 1 magnified 10000 times;
FIG. 4 is a scanning electron micrograph of the vanadium sulfide nanoflower prepared in example 1 magnified 30000 times;
FIG. 5 is a scanning electron micrograph of vanadium sulfide nanoflowers prepared in example 2 magnified 10000 times;
FIG. 6 shows the scan rate of 5-100 mV s-1Cyclic voltammetry of (a);
FIG. 7 shows that the current density is 1-20A g-1The constant current charge-discharge curve of (1);
FIG. 8 shows that the current density is 1-20A g-1Specific capacity of (a);
FIG. 9 is a graph of power density versus energy density;
FIG. 10 shows a constant current density of 2A g-1A cycle stability test chart;
FIG. 11 is a scanning electron micrograph of the products prepared in examples 1 to 4 magnified 10000 times;
FIG. 12 is a scanning electron micrograph of the products prepared in examples 5 to 7 and example 1 magnified 10000 times.
Detailed Description
The present invention will be described in further detail with reference to specific examples.
Example 1
The preparation method of the vanadium sulfide nanoflower comprises the following steps:
(1) mixing sodium orthovanadate dodecahydrate (Na) with the mass ratio of 1:33VO4·12H2O, 0.9 g) and thioacetamide (C)2H5NS, 2.7 g) is dissolved in 30mL of water (the concentration of sodium orthovanadate dodecahydrate is 0.03 g/mL), the obtained mixed solution is placed in a constant-temperature water bath kettle at 25 ℃ and stirred for 60min, and a light yellow precursor solution is obtained;
(2) transferring the obtained precursor solution into a 50mL reaction kettle with a polytetrafluoroethylene lining, placing the reaction kettle in a forced air drying oven at 140 ℃ for hydrothermal reaction for 24 hours, after the reaction is finished, naturally cooling the reaction kettle, sequentially washing the obtained product with deionized water and ethanol for 3 times respectively, and then placing the product in a vacuum drying oven (-0.09 MPa) for drying at 80 ℃ for 12 hours to obtain the vanadium sulfide nanocrystallization.
Example 2
The preparation method of the vanadium sulfide nanoflower comprises the following steps:
(1) mixing sodium orthovanadate dodecahydrate (Na) with the mass ratio of 1:23VO4·12H2O, 0.9 g) and thioacetamide (C)2H5NS, 1.8 g) is dissolved in 30mL of water (the concentration of sodium orthovanadate dodecahydrate is 0.03 g/mL), and the obtained mixed solution is placed in a constant-temperature water bath kettle at 25 ℃ to be stirred for 50min, so that a light yellow precursor solution is obtained;
(2) transferring the obtained precursor solution into a 50mL reaction kettle with a polytetrafluoroethylene lining, placing the reaction kettle in a 160 ℃ forced air drying oven for hydrothermal reaction for 22h, after the reaction is finished, naturally cooling the reaction kettle, sequentially washing the obtained product with deionized water and ethanol for 3 times respectively, and then placing the product in a vacuum drying oven (-0.09 MPa) for drying at 80 ℃ for 12h to obtain the vanadium sulfide nanocrystallization.
Example 3
The preparation method of vanadium sulfide nanoflower in this example is the same as that in example 1, except that the mass ratio of sodium orthovanadate dodecahydrate to thioacetamide in this example is 1: 1.5.
Example 4
The preparation method of vanadium sulfide nanoflower in this example is the same as that in example 1, except that the mass ratio of sodium orthovanadate dodecahydrate to thioacetamide in this example is 1:1.
Examples 5 to 9
The method for preparing vanadium sulfide nanoflowers in this example is the same as in example 1, except that the mass concentrations of sodium orthovanadate dodecahydrate in examples 5, 6, 7, 8 and 9 were 0.005g/mL, 0.015g/mL, 0.06g/mL, 0.025g/mL and 0.045g/mL, respectively.
Composition and morphology characterization of prepared vanadium sulfide nanoflower
(1) Characterization of XRD
FIG. 1 is an XRD analysis of vanadium sulfide nanoflowers prepared in example 1, comparing with standard cards, and finding all diffraction peaks and VS2The agreement shows that the product prepared is VS2。
The vanadium sulfide nanoflowers prepared in examples 2 and 3 and examples 8 and 9 were examined in the same manner, and the results were substantially identical to those of example 1.
(2) TEM characterization
FIG. 2 is a TEM image of the vanadium sulfide nanoflower prepared in example 1, and FIGS. a to d are TEM images at different magnifications, respectively. As can be seen from the figure a, the diameter of the nanoflower is about 3 μm, and the nanoflower is formed by a large number of nanosheets which are diverged from the middle to the periphery, so that the color of the middle part is dark, and the color is lighter and even transparent as the edge is closer. The nanometer flower has band-shaped areas with darker colors at the edges, as shown in figures a and b, which are mainly caused by the folds or curls generated by the nanometer sheets and staggered growth, and the structure is favorable for preventing aggregation and overlapping among the nanometer sheets, thereby increasing the specific surface area of the material and improving the stability. And the picture d is a high-resolution picture of the edge of the nano-sheet, and the nano-sheet only has a very regular lattice fringe, which shows that the nano-sheet only contains a crystal structure and the crystal has better crystallinity. The lattice fringe spacing was found to be 0.57nm by analysis of the lattice fringe spacing, which is comparable to the previous XRD-analyzed structure, with VS and fringe spacing2The distances between crystal faces of the crystal (001) are the same, which shows that the nano-sheet only contains one VS2And (4) crystals. Panel c high power mirror display VS2The nano-sheet is close to a transparent state, which shows that the single-layer nano-sheet is formed by single-layer VS with extremely few layers2The components are as follows.
The vanadium sulfide nanoflowers prepared in examples 2 and 3 and examples 8 and 9 were examined in the same manner, and the results were substantially identical to those of example 1.
(3) SEM characterization
Fig. 3 and 4 are scanning electron microscope images of the vanadium sulfide nanoflower prepared in example 1 magnified 10000 times and 30000 times, and fig. 5 is a scanning electron microscope image of the vanadium sulfide nanoflower prepared in example 2 magnified 10000 times, and it can be seen from the images that the vanadium sulfide nanoflower prepared in the present invention has a loose surface, a uniform appearance, and a large specific surface area, is mainly assembled by nanosheets having a thickness of about 10-20 nm, and a diameter of about 1-3 μm, and the nanoflowers are formed by the nanosheets diffusing from the inside to the periphery, and the nanosheets are prevented from aggregating or overlapping in a manner of wrinkling or curling, etc., so that the nanoflowers a large number of voids, thereby increasing the specific surface area of the sample, facilitating the transfer of ions or electrons during the charging and discharging process, providing more activation sites for the generation of pseudocapacitance, and improving the capacitance of the electrode material.
The vanadium sulfide nanoflowers prepared in example 3 and examples 8 and 9 were examined in the same manner, and the results were substantially identical to those of examples 1 and 2.
Secondly, testing the electrochemical performance of the prepared vanadium sulfide nanoflower
Mixing the vanadium sulfide nanoflower prepared in example 1, acetylene black serving as a conductive agent and polyvinylidene fluoride (PVDF) serving as a binder according to a mass ratio of 7:2:1, dropwise adding N-methylpyrrolidone (NMP) and grinding until the mixture is ground into a slurry, and then uniformly coating the slurry on 1 x 1.5cm rectangular foamed nickel with a coating area of 1cm2And drying the electrode plate in a vacuum drying oven at 80 ℃ for 12 hours to obtain the electrode plate.
The invention uses three electrodes to study the electrochemical properties of the material. In the three electrodes, a platinum electrode is used as a counter electrode, an Ag/AgCl electrode is used as a reference electrode, and 1M NaNO is used3The electrolyte is used for electrochemical performance test. To ensure that the electrode material is fully wetted by the electrolyte, it is soaked in the electrolyte used for 6 hours before the three electrodes are assembled for testing. The electrochemical performance of the material was tested using a Cyclic Voltammetry (CV), constant current charge and discharge (GCD) electrochemical workstation.
(1) Cyclic voltammogram
FIG. 6 is VS2The voltage scanning speed of the super capacitor with the nanometer flower as the electrode material is 5 mV respectively s-1、10 mVs-1、20 mV s-1、30 mV s-1、50 mV s-1And 100 mV s-1The potential window of the cyclic voltammogram (CV curve) of (1.0) to (0) V. The CV curve is not a clear rectangle, and oxidation-reduction peaks exist at the voltage of-0.57V and-0.31V respectively, which indicates that the electrode material has oxidation-reduction reaction in the charge-discharge process and has the property of a Faraday pseudo capacitor. The chemical formula of the electrochemical reaction is as follows:
VS2has a layered structure similar to graphene, and is beneficial to the intercalation/deintercalation of ions or electrons, wherein x in the formula (1) refers to insertion VS2Interlayer of Na+The number of moles of (a). From the CV curves, it can be found that VS occurs when the direction of the scan voltage changes2The nanoflower capacitor has a faster response speed because the present invention converts VS2The nano-sheets are assembled into a nano-flower structure, thereby effectively reducing VS2(iv) aggregate, Single layer VS2The thickness of the nano-sheet is 10-20 nm, and VS is realized at the same time2The nanoflower is provided with a large number of gaps, the specific surface area of the electrode material is increased, the electrode material is favorable for the entry of ions or electrons, more activation sites can be provided due to the large specific surface area, the redox reaction is favorably carried out, and more pseudocapacitances are provided. As the scan rate increases, the peak value of the current also increases synchronously, but the shape of the CV curve is not significantly distorted because of VS2Cell parameters 5.755 Å and 3.221 Å, the structure provides a loosely stacked framework and VS2Is far greater than Na+(1.96 Å) so that sodium ions can still be intercalated/deintercalated within the electrode material at large voltage scan rates, demonstrating the VS prepared by the method of the invention2The nanoflower has better rate capability.
(2) Constant current charge and discharge curve
FIG. 7 shows 1M NaNO as the electrolyte3Time, VS2Super capacitor with nano flower as electrode material at different current densityConstant current charge and discharge curve (GCD) below. From the figure, it is found that the voltage is not linear with time, but has curves with different radians, which shows that the redox reaction occurs during the charging and discharging process, and the faradaic pseudo-capacitance is generated, and is consistent with the CV curve analysis result. Calculating the specific capacity under different current densities according to the formula (2),
the results are shown in FIG. 8, when the current density is 1A g-1When the specific capacity is 554.8F g-1Showing VS prepared by the present invention2The nanomaterial, as analyzed before, is an excellent electrode material, VS2The special graphene-like laminated structure is beneficial to embedding/de-embedding of ions, the metal property can enhance the conductivity, the nano sheets are assembled into the three-dimensional loose nano flower structure, the aggregation is effectively reduced, and the specific surface area of an electrode material is increased. However, as the current density increased, the specific capacity gradually decreased, but even at a current density of 5A g-1Still has 367.2F g-1The specific capacity is maintained by 66.2 percent, which indicates that 1M NaNO is used3When the solution is an electrolyte, VS2The nanoflower supercapacitors have good rate capability, which is also consistent with the analysis of CV curves. However, the specific capacity retention rate is 43.6% when the current density is increased to 20A/g, which is mainly because the current density is increased and the specific capacity is reduced, and the redox reaction is a slow process and takes time due to the transfer of ions or electrons in the electrode material, and because the charge-discharge time is longer at a lower current density, the transfer of ions or electrons and the redox reaction are facilitated, in this case, the ion or electron can reach a larger specific surface area, and the number of active sites for the redox reaction is larger, so that a larger specific capacitance is generated. In contrast, at a high current density, since the charge and discharge process is short, the time for the transfer of ions or electrons, the oxidation-reduction reaction, and the like is not sufficiently long, and insufficient occurs, the specific capacity decreases as the current density increases. On the other hand, becauseThe large current density can cause the over-saturation or over-consumption of the electrolyte, and the increase of the internal resistance and the ionic resistance coefficient is another reason for the reduction of the specific capacity under the large current density.
(3) Power density versus energy density curve
FIG. 9 is VS21M NaNO of super capacitor with NaNO flower as electrode material3Graph (Ragon curve) of power density and energy density in electrolyte, the Ragon curve showing VS2The energy density of the electrode material is related to the power density at a current density of 1A g-1The power density is 450W kg-1Exhibiting 62.4 Wh kg-1Ultra high energy density of (d); at a super high current density of 20A g-1Lower has 9000W kg-1At a high power density of 27.2 Wh kg of energy density-1Indicate VS2The nanometer flower is coated with neutral electrolyte NaNO3Excellent electrochemical behavior in the case of an electrolyte. FIG. 9 also shows the electrode material in some other reports, such as CoS (Power Density of 99.8W kg)-1The hourly energy density was 18.5Wh kg-1）、Ni3S2(Power density 214.6W kg-1The hourly energy density was 8.2 Wh kg-1) CuS (power density 1750W kg)-1The hourly energy density was 6.23 Wh kg-1）、V2O5/PIN (Power Density of 900W kg)-1The hourly energy density was 38.7 Whkg-1) VS prepared according to the invention in comparison with these electrode materials2The nanoflower has strong competitive advantage.
(4) Test for cycling stability
The supercapacitor prepared as described above was charged at 2A g-1The stability of the obtained product is tested under the conditions that the current density and the potential window are-0.9-0V and the constant-current charge-discharge cycle is 500 times, and a graph 10 shows the specific capacity under different cycle times. The specific capacity of the initial electrode material was 500.4F g-1The specific capacity is still as high as 459.4F g after 500 cycles-1The capacitance retention ratio is 91.9%, illustrating the VS prepared by the invention2The capacitor assembled by the nanoflower has higher circulation stability, so thatThe service life is long. Meanwhile, as can be seen from the figure, the specific capacity tends to be stable around 25 times of constant-current charge-discharge cycle, which is mainly VS2The nano sheets are assembled into a three-dimensional nanoflower structure, and the folds of the nano sheets can effectively prevent more laminated VS2The large amount of gaps are beneficial to the rapid entering of the electrolyte, and VS is realized on a microscopic level2The interlayer spacing of the crystal is far greater than that of Na+Diameter of (2) is in favor of Na+Thereby reducing the transport resistance of ions, increasing the specific surface area and enabling the electrode material to show high cycling stability.
From the above discussion, it can be seen that VS is prepared according to the present invention2The nanoflower shows high specific capacity (the current density is 1A g)-1Specific capacity at 554.8F g-1) At the same time, the energy density is high (the current density is 1A g)-1The power density is 450W kg-1The hourly energy density was 62.4 Wh kg-1) High cycle stability (current density of 2A g)-1The capacity retention rate is 91.9 percent after 500 times of time cycle), and the rate performance is excellent (when the current density is increased to 5A g)-1The specific capacity is 367.2F g-1The specific capacity retention rate reaches 66.2 percent), still has very high specific capacity under high current density, and is a super capacitor electrode material with excellent performance.
Influence of the mass ratio and concentration of sodium orthovanadate tri-and dodecahydrate and thioacetamide on the product
(1) Sodium orthovanadate dodecahydrate and thioacetamide in mass ratio
In FIG. 11, (a), (b), (c), and (d) correspond to SEM images of the products prepared in examples 4, 3, 2, and 1 at 10000 times magnification, wherein (c) and (d) are the same as (5) and (3).
As can be seen by comparison, the product in the graph (c) and the graph (d) has a loose surface, uniform appearance and an obvious nanoflower structure, most of the product in the graph (b) has the nanoflower structure but contains a small amount of solid microspheres, while most of the product in the graph (a) is realized microspheres, so that the formation of the nanoflower structure of the product can be influenced by different mass ratios of sodium orthovanadate dodecahydrate to thioacetamide, and the vanadium sulfide nanoflower with good appearance can be prepared in the mass ratio of sodium orthovanadate dodecahydrate to thioacetamide of 1: 1.2-3.5, wherein the mass ratio can be further preferably 1: 2.2-3.5.
(2) Sodium orthovanadate dodecahydrate concentration
In FIG. 12, (a), (b), (c), (d) correspond to SEM images of the products prepared in examples 5, 6, 1 and 7 at 10000 times magnification, wherein the image (c) is the aforementioned image 3.
As can be seen from the graphs, in the graphs (a) and (b), the products are both solid microspheres and do not form a nano-flower structure, while in the graph (d), the products are both nano-sheets and do not form a nano-flower structure, and in the graph (c), the product has uniform morphology and an obvious nano-flower structure, wherein the products prepared in the examples 8 and 9 have an obvious nano-flower structure similar to the graph (c), and it can be seen that the concentration of sodium orthovanadate dodecahydrate also affects the formation of the nano-flower structure of the products.
The above examples of the present invention are merely illustrative of the present invention and are not intended to limit the embodiments of the present invention. Variations and modifications in other variations will occur to those skilled in the art upon reading the foregoing description. Not all embodiments are exhaustive. All obvious changes and modifications of the present invention are within the scope of the present invention.
Claims (3)
1. A preparation method of a supercapacitor electrode material vanadium sulfide nanoflower is characterized by comprising the following steps:
(1) dissolving sodium orthovanadate dodecahydrate and thioacetamide in water to prepare a precursor solution, and stirring at 20-30 ℃ for 30-60 min to obtain the precursor solution; wherein the mass ratio of the sodium orthovanadate dodecahydrate to the thioacetamide is 1:3, and the mass concentration of the sodium orthovanadate dodecahydrate is 0.025-0.045 g/mL;
(2) carrying out hydrothermal reaction on the precursor solution, obtaining a product after the reaction is finished, naturally cooling the reaction kettle after the reaction is finished, sequentially washing the obtained product for 3 times by using deionized water and ethanol respectively, and then placing the product in a vacuum drying oven for drying to obtain the vanadium sulfide nanoflower; wherein the hydrothermal reaction temperature is 130-160 ℃, and the reaction time is 22-26 h.
2. The preparation method of the supercapacitor electrode material vanadium sulfide nanoflower according to claim 1, wherein the product obtained in the step (2) is dried in vacuum at 60-100 ℃.
3. Use of vanadium sulfide nanoflowers prepared according to the method of any one of claims 1 to 2 in supercapacitors, lithium ion batteries or sodium ion batteries.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711377254.5A CN108046320B (en) | 2017-12-19 | 2017-12-19 | Preparation method of supercapacitor electrode material vanadium sulfide nanoflower |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711377254.5A CN108046320B (en) | 2017-12-19 | 2017-12-19 | Preparation method of supercapacitor electrode material vanadium sulfide nanoflower |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108046320A CN108046320A (en) | 2018-05-18 |
| CN108046320B true CN108046320B (en) | 2020-04-14 |
Family
ID=62130121
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201711377254.5A Active CN108046320B (en) | 2017-12-19 | 2017-12-19 | Preparation method of supercapacitor electrode material vanadium sulfide nanoflower |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108046320B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109830666A (en) * | 2019-02-19 | 2019-05-31 | 珠海光宇电池有限公司 | A kind of vanadic anhydride positive electrode and preparation method and application |
| CN110064409B (en) * | 2019-05-10 | 2022-03-11 | 深圳大学 | Pt/VS2Catalytic material, preparation method and application thereof |
| CN110368955B (en) * | 2019-08-12 | 2022-06-07 | 陕西科技大学 | VS (virtual switch)2Preparation method of CdS composite photocatalyst |
| CN113213535A (en) * | 2021-05-13 | 2021-08-06 | 陕西科技大学 | VS capable of being simultaneously applied to positive electrode and negative electrode and with controllable structure2Preparation method of micro-flower electrode material |
| CN113991104B (en) * | 2021-12-30 | 2022-03-25 | 成都大学 | Vanadium-based material and preparation method and application thereof |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105819507A (en) * | 2016-04-29 | 2016-08-03 | 陕西科技大学 | Preparation method and application of nanosheet self-assembled microflower-shaped VS2 |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102010004B (en) * | 2010-12-27 | 2012-05-30 | 中国科学技术大学 | Method for preparing vanadium disulphide nano powder |
| CN107221646B (en) * | 2017-07-13 | 2019-07-16 | 陕西科技大学 | A kind of vanadium disulfide nanometer sheet and its preparation method and application of hydroxide vanadyl cladding |
-
2017
- 2017-12-19 CN CN201711377254.5A patent/CN108046320B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105819507A (en) * | 2016-04-29 | 2016-08-03 | 陕西科技大学 | Preparation method and application of nanosheet self-assembled microflower-shaped VS2 |
Non-Patent Citations (2)
| Title |
|---|
| Synergistic Effect of MoS2 Nanosheets and VS2 for the Hydrogen Evolution Reaction with Enhanced Humidity-Sensing Performance;Xiaofan Chen et al;《Appl. Mater. Interfaces》;20171109;第9卷;摘要，Synthesis of VS2 Nanoflowers，Electrochemical Measurements，第42141-42142页RESULTS AND DISCUSSION，图1-3 * |
| Xiaofan Chen et al.Synergistic Effect of MoS2 Nanosheets and VS2 for the Hydrogen Evolution Reaction with Enhanced Humidity-Sensing Performance.《Appl. Mater. Interfaces》.2017,第9卷 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108046320A (en) | 2018-05-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108046320B (en) | Preparation method of supercapacitor electrode material vanadium sulfide nanoflower | |
| Cheng et al. | One-step controlled synthesis of hierarchical hollow Ni3S2/NiS@ Ni3S4 core/shell submicrospheres for high-performance supercapacitors | |
| Wang et al. | Nitrogen/sulfur co-doped graphene networks uniformly coupled N-Fe2O3 nanoparticles achieving enhanced supercapacitor performance | |
| Meng et al. | Tailoring NiCoAl layered double hydroxide nanosheets for assembly of high-performance asymmetric supercapacitors | |
| Lian et al. | Nb2O5 quantum dots coated with biomass carbon for ultra-stable lithium-ion supercapacitors | |
| Wang et al. | ZnCo 2 O 4@ MnCo 2 O 4 heterojunction structured nanosheets for high-performance supercapacitor | |
| Chen et al. | Fe3O4 nanorods in N-doped carbon matrix with pseudo-capacitive behaviors as an excellent anode for subzero lithium-ion batteries | |
| Li et al. | One-step electrochemical controllable preparation of nickel cobalt sulfide nanosheets and its application in supercapacitors | |
| Zhao et al. | Tuning the morphology and size of NiMoO4 nanosheets anchored on NiCo2O4 nanowires: the optimized core-shell hybrid for high energy density asymmetric supercapacitors | |
| Wang et al. | Hierarchical NiCoP/Co (OH) 2 nanoarrays for high-performance asymmetric hybrid supercapacitors | |
| He et al. | Polycationic bimetallic oxide CoGa 2 O 4 with spinel structure: dominated pseudocapacitance, dual-energy storage mechanism, and Li-ion hybrid supercapacitor application | |
| Lin et al. | Hierarchical design of Ni3S2@ Co9S8 nanotubes for supercapacitors with long cycle-life and high energy density | |
| Wang et al. | Facile preparation of Ni–Mn layered double hydroxide nanosheets/carbon for supercapacitor | |
| Shi et al. | Flake-like carbon coated Mn2SnO4 nanoparticles as anode material for lithium-ion batteries | |
| Fan et al. | High-capacity MnCo2O4 supported by reduced graphene oxide as an anode for lithium-ion capacitors | |
| Liu et al. | 3D nanoflower-like MoS2 grown on wheat straw cellulose carbon for lithium-ion battery anode material | |
| Wei et al. | Design and synthesis of NiCo2O4/NiCoO2/graphene hybrid nanoarrays with enhanced capacitive performance | |
| Jiang et al. | Superior lithium-storage properties derived from a gC 3 N 4-embedded honeycomb-shaped meso@ mesoporous carbon nanofiber anode loaded with Fe 2 O 3 for Li-ion batteries | |
| Wei et al. | High-specific-capacitance supercapacitor based on vanadium oxide nanoribbon | |
| Liang et al. | One-step hydrothermal synthesis of VO2 (B) as cathode materials for high-capacity and high-rate Li-ion batteries | |
| Xiao et al. | Carbon-coated MXene nanofiber as a free-standing electrode for high-performance lithium-ion storage | |
| Ma et al. | Mesoporous carbon-supported flower-like Mn-doped Ni–Co layered double hydroxides with high cycling capacitance retention for supercapacitors | |
| Yuan et al. | NiO loaded on hydrothermally treated mesocarbon microbeads (h-MCMB) and their supercapacitive behaviors | |
| Zhao et al. | Nanoparticle MoO2 composited with biomass-derived carbon micron balls used as enhanced bifunctional cathode materials | |
| Chen et al. | Construction of V1. 11S2 flower spheres for efficient aqueous Zn-ion batteries |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |