CN111933904A - Bimetal sulfide and preparation method thereof, compound and preparation method thereof, lithium-sulfur positive electrode material and lithium-sulfur battery - Google Patents

Bimetal sulfide and preparation method thereof, compound and preparation method thereof, lithium-sulfur positive electrode material and lithium-sulfur battery Download PDF

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CN111933904A
CN111933904A CN202010676740.2A CN202010676740A CN111933904A CN 111933904 A CN111933904 A CN 111933904A CN 202010676740 A CN202010676740 A CN 202010676740A CN 111933904 A CN111933904 A CN 111933904A
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sulfide
lithium
sulfur
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李海军
孙克宁
王振华
赵雪玲
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Yinlong New Energy Co Ltd
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Abstract

The invention provides a bimetallic sulfide and a preparation method thereof, a compound and a preparation method thereof, a lithium-sulfur positive electrode material and a lithium-sulfur battery. The chemical formula of the bimetallic sulfide is MxCo3‑xS4M is selected from any one of Ni, Cu, Mn, V, Fe, Zn and Mo, the shape of the bimetallic sulfide is a hollow porous nanocube structure, wherein x is more than or equal to 0.5 and less than or equal to 1.5. M of hollow porous nanocubesxCo3‑xS4Has high specific surface area (more active sites), and greatly improves M when being used for loading SxCo3‑xS4The sulfur fixation function of the catalyst and the volume expansion caused by charge and discharge are relieved; and then, the double metals (M and Co) with multiple valences play a synergistic role in the catalytic conversion of polysulfide, so that the theoretical capacity of the positive electrode material of the lithium-sulfur battery is improved, and the rate capability and the cycle performance of the lithium-sulfur battery are improved.

Description

Bimetal sulfide and preparation method thereof, compound and preparation method thereof, lithium-sulfur positive electrode material and lithium-sulfur battery
Technical Field
The invention relates to the technical field of lithium-sulfur batteries, and particularly relates to a bimetallic sulfide and a preparation method thereof, a compound and a preparation method thereof, a lithium-sulfur positive electrode material and a lithium-sulfur battery.
Background
Due to the development of economy, the growth of population, and the change of traditional life style, the demand of modern society for energy is increasing. However, with the rapid increase of the usage amount of chemical fuels, the problem of environmental pollution is increasing, and people are concerned about this problem. To solve this problem, it has become important to reduce the dependence on fossil fuels and to search for new renewable energy sources. Lithium ion batteries have been widely used in the past 20 years due to their high energy density, low cost, portability, and other features. However, current lithium ion battery technology is based primarily on the study of intercalation composite anode and cathode materials, which severely limits their charge storage capacity and energy density. The capacity of the plug-in oxide cathode is difficult to reach 250mAh g at present-1. On the other hand, the capacity of the graphite anode is limited to 370mAh g-1. In order to overcome the charge storage limitation caused by the intercalation and deintercalation mode of lithium ion batteries, in recent years, lithium sulfur batteries using a conversion reaction as a mechanism have attracted more and more attention. Sulfur is one of the most abundant elements in the earth crust, and elemental sulfur is mainly S on earth8Exist in the form of (1). The lithium-sulfur battery using sulfur as the anode material has a theoretical specific capacity up to 1672mAh g-1Far higher than the current commercial lithium ion battery, is considered to have the most research and application price at presentOne of the lithium secondary battery systems of value.
Although the lithium-sulfur battery has the advantages of high capacity, high specific capacity, low production cost, environmental friendliness and the like, the problems of low utilization rate of active substances, short cycle life, poor safety and the like still exist at present, and the commercial application of the lithium-sulfur battery is severely restricted. The reasons for the above problems are mainly the following: (1) insulation problem of S: the room temperature conductivity of the elemental sulfur is only 5 multiplied by 10-30S·cm-1(ii) a (2) Shuttle effect: lithium polysulfide intermediate Li produced in electrode reaction2Sx(6<x is less than or equal to 8) is very soluble in solvent DME and DOL and passes through the diaphragm to react with metallic lithium to generate solid Li2S, resulting in irreversible loss of the active substance S, reduced coulombic efficiency, and also resulting in indefinite charging and poor charging due to a severe shuttle effect. (4) Volume expansion: due to sulfur (2.07g cm)-3) And the final product Li2S(1.66g·cm-3) The volume expansion generated in the charging and discharging process of the battery is about 80%, and the continuous shrinkage and expansion of the volume easily cause pulverization of the anode material in long-term circulation, thereby seriously influencing the capacity problem of the lithium-sulfur battery.
In recent years, researchers have made sulfur-based composite positive electrode materials by using sulfur as an active material and a nonpolar material, such as carbon materials such as activated carbon, mesoporous carbon, graphene, carbon nanotubes, and carbon nanofibers, polymers such as polyacrylonitrile, polyaniline polypyrrole, and the like, or a matrix material having a specific structure such as a polar material metal oxide, metal sulfide, or metal carbide/nitride, and the like, thereby significantly improving cycle performance and rate performance of a lithium-sulfur battery.
However, in the current lithium-sulfur battery positive electrode, the prepared single metal sulfide or a plurality of metal sulfides doped as active sites have the problem of distribution uniformity and depend on the pore structure and the surface area of a substrate material; the graphene and carbon nanotube materials have poor dispersibility, and the substrate materials are easy to aggregate in the preparation process, so that the active substances are likely to be dispersed unevenly, the utilization rate of the active substances is reduced, the electrode polarization is increased, and the capacity performance and the rate performance of the battery are affected.
Disclosure of Invention
The invention mainly aims to provide a bimetallic sulfide and a preparation method thereof, a compound and a preparation method thereof, a lithium-sulfur positive electrode material and a lithium-sulfur battery, so as to solve the problem that the lithium-sulfur battery in the prior art is poor in capacity performance and cycle performance.
In order to achieve the above object, according to one aspect of the present invention, there is provided a bimetallic sulfide having a chemical formula of MxCo3-xS4M is selected from any one of Ni, Cu, Mn, V, Fe, Zn and Mo, the shape of the bimetallic sulfide is a hollow porous nanocube structure, wherein x is more than or equal to 0.5 and less than or equal to 1.5.
Further, the porous nanocube has a ridge length of 450 to 550nm, preferably the pore diameter of the bimetallic sulfide is 2 to 6nm, and preferably the specific surface area of the bimetallic sulfide is 25 to 40m2/g。
According to another aspect of the present invention, there is provided a method for preparing a bimetallic sulfide, comprising the step of S1, subjecting M to an acid solutionxCo3-x[Co(CN)6]2Etching the precursor to obtain a hollow MxCo3-x[Co(CN)6]2(ii) a Step S2, making the hollow MxCo3-x[Co(CN)6]2Calcining to obtain bimetal sulfide2S, preferably containing H2The gas of S is H2S and N2Or a mixture comprising H2S and inert gas.
Further, the etching process comprises the steps of adding an acid solution, a surfactant and MxCo3-x[Co(CN)6]2And (3) etching after mixing the precursors, preferably selecting a surfactant from polyvinylpyrrolidone or hexadecyl trimethyl ammonium bromide, preferably selecting an acid solution from one or more of hydrochloric acid, nitric acid aqueous solution and sulfuric acid aqueous solution, wherein the hydrogen ion concentration in the acid solution is 1-5 mol/L, and preferably selecting MxCo3-x[Co(CN)6]2The mass ratio of the precursor to the surfactant is 1: 5-1: 7, and the preferred etching treatment temperature is 140-200 ℃.
Further, the above M is calculated as hydrogen ionxCo3-x[Co(CN)6]2The molar ratio of the precursor to the acid solution is 1:2 × 104～1:10×104。
Further, the above-mentioned H2S and hollow MxCo3-x[Co(CN)6]2In the molar ratio of 4:1 to 8:1, preferably H in the mixed gas2The volume fraction of S is 5-15%.
Further, the calcination process comprises subjecting the hollow M to calcinationxCo3-x[Co(CN)6]2Heating to 350-400 ℃ in the mixed gas at the speed of 2-5 ℃/min to obtain a calcined intermediate, and preferably calcining for 3-5 h; and cooling the calcined intermediate to 20-25 ℃ in the mixed gas at the speed of 2-5 ℃/min to obtain the bimetallic sulfide.
According to yet another aspect of the present invention, there is provided a complex, wherein the complex is MxCo3-xS4-S complex in the presence of MxCo3-xS4-M in S ComplexxCo3-xS4The mass ratio of S to S is 1: 4 to 5.
According to yet another aspect of the present invention, there is provided a method for preparing a complex, the method comprising mixing MxCo3-xS4Suspension and S8Mixing the solutions to obtain a mixture; and adjusting the pH value of the mixture to 6-7, stirring, washing and drying to obtain the compound, wherein the preferable stirring time is 8-10 h.
Further, M is as defined abovexCo3-xS4The solid content of the suspension is 0.25-0.3 mg/mL, and S is preferably selected8Solution of S8The element is dissolved in aqueous solution of sulfide salt, preferably S8The mass ratio of the simple substance to the sulfide salt is 1: 12.5 to 15, preferably the concentration of the aqueous solution of the sulfide salt is 1.6 to 1.8mol/L, and the aqueous solution of the sulfide salt is selected from any one of aqueous sodium sulfide solution, aqueous potassium sulfide solution and aqueous ammonium sulfide solutionOne or more of them.
According to still another aspect of the present invention, there is provided a lithium sulfur positive electrode material including a sulfur-containing composite, the sulfur-containing composite being the above-described composite.
According to another aspect of the present invention, a lithium-sulfur battery is provided, which includes a positive electrode and a negative electrode, wherein the positive electrode is the lithium-sulfur positive electrode material.
By applying the technical scheme of the invention, MxCo3-xS4The material is a sulfide material with a spinel structure, and the delocalized electronic structure of the material enables the material to have higher ionic and electronic conductivity; m of hollow porous nanocubesxCo3-xS4Has high specific surface area (more active sites), if M is usedxCo3-xS4For S loading, on one hand, on the basis that a large amount of S enters a cavity in the hollow porous nanocube through a pore passage on the surface of the hollow porous nanocube, a part of S is adsorbed on the surface of the hollow porous nanocube, so that M is greatly improvedxCo3-xS4Sulfur fixation of (5) to obtain M containing a large amount of SxCo3-xS4-S complex, on the other hand, to mitigate volume expansion associated with charging and discharging; m of simultaneously stronger polarityxCo3-xS4The method is favorable for combination with polysulfide ions to form a TM-S covalent bond, the TM-S covalent bond has strong binding energy and electron transfer capacity, so that effective chemical adsorption and conversion of polysulfide are favorably realized, and then the catalytic conversion of polysulfide is performed by bimetal (M and Co) with multiple valences, so that the shuttle effect of polysulfide ions is greatly reduced, the theoretical capacity of the positive electrode material of the lithium-sulfur battery is improved, and the rate capability and the cycle performance of the lithium-sulfur battery are improved.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 shows Cu obtained in example 15/3Co4/3[Co(CN)6]2Scanning electron microscope images of the precursor;
FIG. 2 shows Cu shown in FIG. 15/3Co4/3[Co(CN)6]2A partial enlarged view of the precursor;
FIG. 3 shows the hollow CuCo obtained in example 12S4Scanning electron microscope images of;
FIG. 4 illustrates the hollow CuCo shown in FIG. 12S4A partial enlargement of the medium crushing structure;
FIG. 5 shows the hollow CuCo obtained in example 12S4Transmission electron microscopy images of;
FIG. 6 shows the hollow CuCo obtained in example 12S4XRD spectrum of (1); and
fig. 7 is a graph showing cycle performance at 0.2C rate of the lithium sulfur battery obtained in example 1.
Detailed Description
It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail below with reference to the embodiments with reference to the attached drawings.
As analyzed by the background art, the problem of poor capacity performance and cycle performance of lithium-sulfur batteries exists in the prior art, and in order to solve the problem, the invention provides a bimetallic sulfide and a preparation method thereof, a compound and a preparation method thereof, a lithium-sulfur positive electrode material and a lithium-sulfur battery.
In an exemplary embodiment of the present application, a bimetallic sulfide is provided having the formula MxCo3-xS4M is selected from any one of Ni, Cu, Mn, V, Fe, Zn and Mo, the shape of the bimetallic sulfide is a hollow porous nanocube structure, wherein x is more than or equal to 0.5 and less than or equal to 1.5.
Due to MxCo3-xS4The sulfide material with spinel structure has delocalized electronic structure to make it have higher ionic and electronic chargeConductivity; m of hollow porous nanocubesxCo3-xS4Has high specific surface area (more active sites), if M is usedxCo3-xS4For S loading, on one hand, on the basis that a large amount of S enters a cavity in the hollow porous nanocube through a pore passage on the surface of the hollow porous nanocube, a part of S is adsorbed on the surface of the hollow porous nanocube, so that M is greatly improvedxCo3-xS4Sulfur fixation of (5) to obtain M containing a large amount of SxCo3-xS4-S complex, on the other hand, to mitigate volume expansion associated with charging and discharging; m of simultaneously stronger polarityxCo3-xS4The method is favorable for combination with polysulfide ions to form a TM-S covalent bond, the TM-S covalent bond has strong binding energy and electron transfer capacity, so that effective chemical adsorption and conversion of polysulfide are favorably realized, and then the catalytic conversion of polysulfide is performed by bimetal (M and Co) with multiple valences, so that the shuttle effect of polysulfide ions is greatly reduced, the theoretical capacity of the positive electrode material of the lithium-sulfur battery is improved, and the rate capability and the cycle performance of the lithium-sulfur battery are improved.
In one embodiment of the present application, the porous nanocube has a ridge length of 450 to 550nm, preferably the pore diameter of the bimetallic sulfide is 2 to 6nm, and preferably the specific surface area of the bimetallic sulfide is 25 to 40m2/g。
Porous nanocube-shaped M of the above-mentioned size when the bimetallic sulfide of the present application is applied to the positive electrode material of a lithium-sulfur batteryxCo3-xS4The lithium-sulfur battery has larger specific surface area, thereby being more beneficial to the solidification of sulfur, obtaining the cathode material loaded with sulfur as much as possible, relieving the volume expansion caused by charging and discharging, and further improving the performance of the lithium-sulfur battery.
In another exemplary embodiment of the present application, there is provided a method for preparing the above-mentioned bimetallic sulfide, comprising the step of S1, subjecting M to an acid solutionxCo3-x[Co(CN)6]2Etching the precursor to obtain a hollow MxCo3-x[Co(CN)6]2(ii) a Step S2, making the hollow MxCo3-x[Co(CN)6]2Calcining to obtain bimetal sulfide2S, preferably containing H2The gas of S is H2S and N2Or a mixture comprising H2S and inert gas.
By acid solution to MxCo3-x[Co(CN)6]2Etching the precursor to obtain the hollow M with porous surfacexCo3-x[Co(CN)6]2Porous hollow MxCo3-x[Co(CN)6]2Then H is added2And calcining the obtained product in the S gas to obtain the spinel-type hollow bimetallic sulfide with porous surface, wherein the preparation method is simple and easy for industrialization.
In one embodiment of the present application, the etching process includes applying an acid solution, a surfactant, and MxCo3-x[Co(CN)6]2And (3) etching after mixing the precursors, preferably selecting a surfactant from polyvinylpyrrolidone or hexadecyl trimethyl ammonium bromide, preferably selecting an acid solution from one or more of hydrochloric acid, nitric acid aqueous solution and sulfuric acid aqueous solution, wherein the hydrogen ion concentration in the acid solution is 1-5 mol/L, and preferably selecting MxCo3-x[Co(CN)6]2The mass ratio of the precursor to the surfactant is 1: 5-1: 7, and the preferred etching treatment temperature is 140-200 ℃.
The above surfactant (organic macromolecule) is coated on MxCo3-x[Co(CN)6]2Surface of the cube of the precursor, thereby at MxCo3-x[Co(CN)6]2The cubic surface of the precursor forms a certain protective layer. At the etching treatment temperature of 140-200 ℃, a large amount of solutes in the acid solution are converted into acidic gas solutes, water is converted into water vapor, and a large amount of acidic gas solutes and water vapor permeate into the M through the protective layer along with the increase of the acidic gas solutes and the water vaporxCo3-x[Co(CN)6]2The cubic interior of the precursor reacts with its internal complex, on the one hand, the dissolution of M and Co makes M reactxCo3-x[Co(CN)6]2A certain cavity is formed inside the cube of the precursor, and simultaneously CN-Reacting with acid gas solute and water vapor to produce HCN and CO2Over time, HCN and CO2From MxCo3-x[Co(CN)6]2The cubic interior of the precursor escapes, thereby further enriching MxCo3-x[Co(CN)6]2Cubic surface porosity of the precursor, while the protective layer reduces the acid gas pair MxCo3-x[Co(CN)6]2The corrosive nature of the cubic surfaces of the precursor, which in turn forms a porous and hollow bimetallic sulfide. The concentration of the acid solution is too low, the required volume of the acid solution is too large, the workload of post-treatment is increased, and the concentration of the acid solution is too high, on one hand, the corrosiveness is too strong, and part M is causedxCo3-x[Co(CN)6]2The cubic structure of the precursor is completely damaged, so that the obtained bimetallic sulfide is not beneficial to fixing sulfur, and therefore, in order to take the effects of the two aspects into consideration, the acid solution with the concentration and the proportion of the surfactant are beneficial to MxCo3-x[Co(CN)6]2The cubic surface of the precursor can form enough protection effect, and simultaneously, the performance of other active ingredients cannot be influenced due to the excessive addition of the precursor.
In order to improve the etching effect of the acid solution and obtain the bimetallic sulfide with rich pores as much as possible, thereby improving the sulfur fixing capacity of the bimetallic sulfide, M is preferably calculated by hydrogen ionsxCo3-x[Co(CN)6]2The molar ratio of the precursor to the acid solution is 1:2 × 104～1:10×104。
To ensure hollowness MxCo3-x[Co(CN)6]2Conversion to bimetallic sulfide as far as possible, preferably H as described above2S and hollow MxCo3-x[Co(CN)6]2In the molar ratio of 4:1 to 8:1, preferably H in the mixed gas2The volume fraction of S is 5-15%.
In one embodiment of the present application, the calcination process comprises subjecting the hollow M to calcinationxCo3-x[Co(CN)6]2Heating to 350-400 ℃ in the mixed gas at the speed of 2-5 ℃/min to obtain a calcined intermediate, and preferably calcining for 3-5 h; and cooling the calcined intermediate to 20-25 ℃ in the mixed gas at the speed of 2-5 ℃/min to obtain the bimetallic sulfide.
The control of the temperature rise and the temperature drop is beneficial to reducing the crushing of bimetallic sulfide particles, and the control of the calcining temperature and the calcining time is beneficial to enabling M to be in a state of being heatedxCo3-x[Co(CN)6]2Complete conversion to MxCo3-xS4。
In yet another exemplary embodiment of the present application, a complex is provided, the complex being MxCo3-xS4-S complex in the presence of MxCo3-xS4-M in S ComplexxCo3-xS4The mass ratio of S to S is 1: 4 to 5.
M of the above mass ratioxCo3-xS4The S complex is loaded with more sulfur, and the M isxCo3-xS4the-S composite is used as a positive electrode material of the lithium-sulfur battery, and can remarkably improve the electrical performance of the lithium-sulfur battery.
In another exemplary embodiment of the present application, there is provided a method for preparing the aforementioned complex, which comprises mixing MxCo3-xS4Suspension and S8Mixing the solutions to obtain a mixture; and adjusting the pH value of the mixture to 6-7, stirring, washing and drying to obtain the compound, wherein the preferable stirring time is 8-10 h.
The control of the pH and the stirring conditions described above contributes to MxCo3-xS4Suspension and S8Thorough mixing of the solution, thereby increasing MxCo3-xS4And S8And then S is determined8Is fixed at MxCo3-xS4In this way, M with a high load S is obtainedxCo3-xS4-an S complex.
In an embodiment of the present application, the M isxCo3-xS4The solid content of the suspension is 0.25-0.3 mg/mL, and S is preferably selected8Solution of S8The element is dissolved in aqueous solution of sulfide salt, preferably S8The mass ratio of the simple substance to the sulfide salt is 1: 12.5-15, preferably the concentration of the sulfide salt water solution is 1.6-1.8 mol/L, and the sulfide salt water solution is selected from one or more of sodium sulfide water solution, potassium sulfide water solution and ammonium sulfide water solution.
Due to S8Insoluble in water, dissolving S in8Dissolving the simple substance in aqueous solution of sulfide salt to obtain water-soluble polysulfide ion, and reacting with MxCo3-xS4M of the suspensionxCo3-xS4Sufficient contact to permit introduction of polysulfide ions into MxCo3-xS4Pores and surfaces of, S8The mass ratio of the simple substance to the sulfide salt and the concentration of the sulfide salt aqueous solution are controlled within the above range, which is favorable for S8Temporary conversion of simple substances into soluble polysulphides, M in the abovementioned solids content rangexCo3-xS4The suspension is more beneficial to reacting with S8The action of polysulfide ions in the solution to obtain M fully loaded with sulfurxCo3-xS4-an S complex.
In yet another exemplary embodiment of the present application, there is provided a lithium sulfur positive electrode material including a sulfur-containing composite, the sulfur-containing composite being the aforementioned composite.
By using MxCo3-xS4The lithium-sulfur positive electrode material obtained from the-S compound improves the theoretical capacity of the positive electrode material of the lithium-sulfur battery, and improves the rate capability and cycle performance of the lithium-sulfur battery.
In another exemplary embodiment of the present application, a lithium sulfur battery is provided, which includes a positive electrode and a negative electrode, wherein the positive electrode is the aforementioned lithium sulfur positive electrode material.
The lithium-sulfur positive electrode material with improved rate capability and cycle performance is used as the positive electrode material of the lithium-sulfur battery, so that the performance and the service life of the lithium-sulfur battery can be obviously improved.
The advantageous technical effects of the present application will be described below with reference to specific examples and comparative examples.
Examples 1 to 29 are MxCo3-xS4Preparation examples of
Example 1
Cu5/3Co4/3[Co(CN)6]2Preparing a precursor:
mixing CuSO4·5H2O (0.25mmol) and CoCl2·6H2Solution A was prepared by dissolving O (0.2mmol) in 200mL ethanol, followed by the addition of sodium citrate (2.25 mmol). Subsequently, K is added3[Co(CN)6](0.3mmol) was dissolved in 100mL of ethanol to prepare solution B. The solution B was dropped into the solution A under magnetic stirring, and the two solutions were thoroughly mixed under magnetic stirring. Standing for 24 hours at room temperature, centrifuging, washing for 3-4 times by using ethanol to obtain a precipitate, and drying at 60 ℃ for 12 hours to obtain hollow Cu5/3Co4/3[Co(CN)6]2As shown in FIGS. 1 and 2, Cu5/3Co4/3[Co(CN)6]2The shape of the precursor is cubic.
Hollow Cu5/3Co4/3[Co(CN)6]2The preparation of (1):
the obtained precipitate Cu5/3Co4/3[Co(CN)6]2The precursor (20mg) was added with polyvinylpyrrolidone (PVP, K30) (100mg) to a hydrochloric acid solution (20mL, 5mol/L concentration) in a Teflon vessel, stirred for 2h, the vessel was transferred to a stainless steel autoclave, and then heated in an electric furnace at 150 ℃ for 3 hours. Standing for 24h, centrifuging, washing with ethanol for 3-4 times, and drying at 60 ℃ for 12h to obtain hollow Cu5/3Co4/3[Co(CN)6]2Wherein, Cu5/3Co4/3[Co(CN)6]2The molar ratio of the precursor to the hydrochloric acid is 1:6 multiplied by 104，Cu5/3Co4/3[Co(CN)6]2The mass ratio of the precursor to the polyvinylpyrrolidone is 1: 5.
CuCo2S4The preparation of (1):
100mg of hollow Cu5/3Co4/3[Co(CN)6]2Is arranged at H2S/Ar Mixed gas (volume fraction of 5% H)2S，H2S and hollow Cu5/3Co4/3[Co(CN)6]2In the molar ratio of 6:1), calcining for 3h at the temperature of 350 ℃ (the heating rate is 2 ℃/min), cooling to room temperature at the rate of 2 ℃/min to obtain the bimetallic sulfide CuCo2S4. From FIG. 3, it can be seen that a part of Cu is etched by the acid solution5/3Co4/3[Co(CN)6]2The structure of the precursor is broken, it can be determined from the broken porous nanocube structure in fig. 4, the morphology of the bimetallic sulfide obtained by the acid solution etching treatment is a hollow porous nanocube structure with a cavity at the center, the distance between the lattices of the bimetallic sulfide shown in fig. 5 and the XRD pattern of the bimetallic sulfide shown in fig. 6 further prove that the bimetallic sulfide is CuCo2S4. FIG. 7 shows CuCo2S4The prepared battery has a cycle performance curve chart under the multiplying power of 0.2C, and the battery has excellent multiplying power performance and cycle performance. The bimetallic sulfide CuCo2S4The nano cube structure has the edge length of 500nm, the aperture of 2-4 nm and the specific surface area of 35m2/g。
Example 2
Example 2 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the molar ratio of the precursor to the hydrochloric acid is 1:2 × 104Finally obtaining the bimetal sulfide CuCo2S4. The nano cubic structure has the edge length of 480nm, the pore diameter of 2-5 nm and the specific surface area of 25m2/g。
Example 3
Example 3 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the molar ratio of the precursor to the hydrochloric acid is 1:10 multiplied by 104Finally obtaining the bimetal sulfide CuCo2S4. The edge length of the nano cubic structure is 530nm, the pore diameter is 2-6 nm, and the specific surface area is 40m2/g。
Example 4
Example 4 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the molar ratio of the precursor to the hydrochloric acid is 1:104Finally obtaining the bimetal sulfide CuCo2S4. The nano cubic structure has the edge length of 450nm, the pore diameter of 2-3 nm and the specific surface area of 20m2/g。
Example 5
Example 5 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the mass ratio of the precursor to the polyvinylpyrrolidone is 1:6, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 550nm, the pore diameter of 2-4 nm and the specific surface area of 32m2/g。
Example 6
Example 6 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the mass ratio of the precursor to the polyvinylpyrrolidone is 1:7, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 450nm, the pore diameter of 3-5 nm and the specific surface area of 30m2/g。
Example 7
Example 7 differs from example 1 in that,
Cu5/3Co4/3[Co(CN)6]2the mass ratio of the precursor to the polyvinylpyrrolidone is 1:3, and finally the bimetallic sulfide CuCo is obtained2S4. The edge length of the nano cubic structure is 700nm, the pore diameter is 2-3 nm, and the specific surface area is 22m2/g。
Example 8
Example 8 differs from example 1 in that,
the concentration of the hydrochloric acid is 3mol/L, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 480nm, the pore diameter of 2-4 nm and the specific surface area of 30m2/g。
Example 9
Example 9 differs from example 1 in that,
the concentration of the hydrochloric acid is 1mol/L, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 520nm, the pore diameter of 2-3 nm and the specific surface area of 27m2/g。
Example 10
Example 10 differs from example 1 in that,
the concentration of the hydrochloric acid is 0.5mol/L, and the bimetallic sulfide CuCo is finally obtained2S4. The nano cubic structure has the edge length of 500nm, the pore diameter of 1-3 nm and the specific surface area of 20m2/g。
Example 11
Example 11 differs from example 1 in that,
H2s and hollow Cu5/3Co4/3[Co(CN)6]2The molar ratio of (1) to (8) to obtain the final bimetal sulfide CuCo2S4. The nano cubic structure has the edge length of 540nm, the pore diameter of 2-5 nm and the specific surface area of 37m2/g。
Example 12
Example 12 differs from example 1 in that,
H2s and hollow Cu5/3Co4/3[Co(CN)6]2The molar ratio of (1) to (4) to obtain the final bimetal sulfide CuCo2S4. The edge length of the nano cubic structure is 520nm, the pore diameter is 2-4 nm, and the specific surface area is 30m2/g。
Example 13
Example 13 differs from example 1 in that,
H2s and hollow Cu5/3Co4/3[Co(CN)6]2The molar ratio of the metal sulfide to the metal sulfide is 2:1, and finally the bimetal sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 600nm, the pore diameter of 2-3 nm and the specific surface area of 23m2/g。
Example 14
Example 14 differs from example 1 in that,
h in the mixed gas2The volume fraction of S is 10 percent, and finally the bimetallic sulfide CuCo is obtained2S4. The edge length of the nano cubic structure is 480nm, the pore diameter is 2-4 nm, and the specific surface area of the bimetallic sulfide is 38m2/g。
Example 15
Example 15 differs from example 1 in that,
h in the mixed gas2The volume fraction of S is 15 percent, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 500nm, the pore diameter of 2-6 nm and the specific surface area of 40m2/g。
Example 16
Example 16 differs from example 1 in that,
h in the mixed gas2The volume fraction of S is 3 percent, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 550nm, the pore diameter of 2-4 nm and the specific surface area of 25m2/g。
Example 17
Example 17 differs from example 1 in that,
calcining at 370 deg.C (heating rate of 2 deg.C/min) for 4 hr, cooling to room temperature at 2 deg.C/min to obtain final product2S4. The edge length of the nano cubic structure is 500nm, the pore diameter is 3-6 nm, and the specific surface area is 38m2/g。
Example 18
Example 18 differs from example 1 in that,
calcining at 400 deg.C (heating rate of 2 deg.C/min) for 5 hr, cooling to room temperature at 2 deg.C/min to obtain bisMetal sulfide CuCo2S4. The nano cubic structure has the edge length of 550nm, the pore diameter of 4-6 nm and the specific surface area of 40m2/g。
Example 19
Example 19 differs from example 1 in that,
calcining at 300 deg.C (heating rate of 2 deg.C/min) for 3 hr, cooling to room temperature at 2 deg.C/min to obtain final product2S4. The nano cubic structure has the edge length of 520nm, the pore diameter of 2-4 nm and the specific surface area of 28m2/g。
Example 20
Example 20 differs from example 1 in that,
the heating rate is 3 ℃/min, the calcination is carried out for 3h, the temperature is cooled to the room temperature at the rate of 3 ℃/min, and finally the bimetal sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 480nm, the pore diameter of 2-5 nm and the specific surface area of 34m2/g。
Example 21
Example 21 differs from example 1 in that,
the heating rate is 5 ℃/min, the calcination is carried out for 3h, the temperature is cooled to the room temperature at the rate of 5 ℃/min, and finally the bimetal sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 450nm, the pore diameter of 3-6 nm and the specific surface area of 38m2/g。
Example 22
Example 22 differs from example 1 in that,
the heating rate is 1 ℃/min, the calcination is carried out for 3h, the temperature is cooled to the room temperature at the rate of 1 ℃/min, and finally the bimetal sulfide CuCo is obtained2S4. The edge length of the nano cubic structure is 500nm, the pore diameter is 2-4 nm, and the specific surface area is 30m2/g。
Example 23
Example 23 differs from example 1 in that,
the surfactant is cetyl trimethyl ammonium bromide, and finally the bimetal sulfide CuCo is obtained2S4. Its nanocube structureHas a ridge length of 400nm, a pore diameter of 3-6 nm, and a specific surface area of 35m2/g。
Example 24
Example 24 differs from example 1 in that,
the acid solution is nitric acid aqueous solution, and finally the bimetallic sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 480nm, the pore diameter of 2-4 nm and the specific surface area of 35m2/g。
Example 25
Example 25 differs from example 1 in that,
the temperature of the etching treatment is 140 ℃, and finally the bimetal sulfide CuCo is obtained2S4. The edge length of the nano cubic structure is 550nm, the pore diameter is 2-4 nm, and the specific surface area is 30m2/g。
Example 26
Example 26 differs from example 1 in that,
the temperature of the etching treatment is 200 ℃, and finally the bimetal sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 450nm, the pore diameter of 3-6 nm and the specific surface area of 40m2/g。
Example 27
Example 27 differs from example 1 in that,
the temperature of the etching treatment is 130 ℃, and finally the bimetal sulfide CuCo is obtained2S4. The nano cubic structure has the edge length of 550nm, the pore diameter of 2-3 nm and the specific surface area of 28m2/g。
Example 28
Ni5/3Co4/3[Co(CN)6]2Preparing a precursor:
mixing Ni (NO)3)2·6H2O (0.25mmol) and CoCl2·6H2Solution A was prepared by dissolving O (0.2mmol) in 200mL ethanol, followed by the addition of sodium citrate (2.25 mmol). Subsequently, K is added3[Co(CN)6](0.3mmol) was dissolved in 100mL of ethanol to prepare solution B. Dripping the solution B into the solution A under magnetic stirring, and allowing the two solutions to react under magnetic stirringAnd (4) fully mixing. Standing for 24 hours at room temperature, centrifuging, washing for 3-4 times by using ethanol to obtain precipitate, and drying at 60 ℃ for 12 hours to obtain Ni5/3Co4/3[Co(CN)6]2And (3) precursor.
Hollow Ni5/3Co4/3[Co(CN)6]2The preparation of (1):
precipitating Ni obtained5/3Co4/3[Co(CN)6]2The precursor (20mg) was added with polyvinylpyrrolidone (PVP, K30) (100mg) to a hydrochloric acid solution (20mL, 5mol/L concentration) in a Teflon vessel, stirred for 2h, the vessel was transferred to a stainless steel autoclave, and then heated in an electric furnace at 150 ℃ for 3 hours. Standing for 24h, centrifuging, washing with ethanol for 3-4 times, and drying at 60 deg.C for 12h to obtain hollow Ni5/3Co4/3[Co(CN)6]2In which Ni5/3Co4/3[Co(CN)6]2The molar ratio of the precursor to the hydrochloric acid is 1:6 multiplied by 104，Ni5/3Co4/3[Co(CN)6]2The mass ratio of the precursor to the polyvinylpyrrolidone is 1: 6.
NiCo2S4The preparation of (1):
100mg of hollow Ni5/3Co4/3[Co(CN)6]2Is arranged at H2S/Ar Mixed gas (volume fraction of 5% H)2S，H2S and hollow Ni5/3Co4/3[Co(CN)6]2In the molar ratio of 6:1), calcining for 3h at the temperature of 350 ℃ (the heating rate is 2 ℃/min), cooling to room temperature at the rate of 2 ℃/min to obtain the bimetallic sulfide NiCo2S4The nano cubic structure has the edge length of 450nm, the pore diameter of 2-6 nm and the specific surface area of 40m2/g。
Example 29
Mn5/3Co4/3[Co(CN)6]2Preparing a precursor:
mixing Mn (CH)3COO)2·4H2O (0.25mmol) and CoCl2·6H2O (0.2mmol) was dissolved in 200mL ethanol, followed by addition of citric acidSodium (2.25mmol) solution A was prepared. Subsequently, K is added3[Co(CN)6](0.3mmol) was dissolved in 100mL of ethanol to prepare solution B. The solution B was dropped into the solution A under magnetic stirring, and the two solutions were thoroughly mixed under magnetic stirring. Standing for 24 hours at room temperature, centrifuging, washing for 3-4 times by using ethanol to obtain precipitate, and drying at 60 ℃ for 12 hours to obtain Mn5/3Co4/3[Co(CN)6]2And (3) precursor.
Hollow Mn5/3Co4/3[Co(CN)6]2The preparation of (1):
the obtained precipitated Mn5/3Co4/3[Co(CN)6]2The precursor (20mg) was added with polyvinylpyrrolidone (PVP, K30) (100mg) to a solution of hydrochloric acid (20mL, 5mol/L) in a Teflon container. Stirred for 2h, the vessel was transferred to a stainless steel autoclave and then heated in an electric furnace at 150 ℃ for 3 h. Standing for 24h, centrifuging, washing with ethanol for 3-4 times, and drying at 60 ℃ for 12h to obtain hollow Mn5/3Co4/3[Co(CN)6]2Wherein, Mn5/3Co4/3[Co(CN)6]2The molar ratio of the precursor to the hydrochloric acid is 1:6 multiplied by 104，Mn5/3Co4/3[Co(CN)6]2The mass ratio of the precursor to the polyvinylpyrrolidone is 1: 6.
MnCo2S4The preparation of (1):
mixing hollow Mn5/3Co4/3[Co(CN)6]2Is arranged at H2S/Ar mixed gas (containing 5% by volume of H)2S，H2S and hollow Mn5/3Co4/3[Co(CN)6]2In the molar ratio of 6:1), calcining for 3h at the temperature of 350 ℃ (the heating rate is 2 ℃/min), cooling to room temperature at the rate of 2 ℃/min to obtain the bimetallic sulfide MnCo2S4The nano cubic structure has the edge length of 550nm, the pore diameter of 2-5 nm and the specific surface area of 30m2/g。
Examples 30 to 35 are complexes (M)xCo3-xS4Preparation example of-S Complex)
M is as followsxCo3-xS4Preparation of-S Complex M used in the examplesxCo3-xS4M prepared for any of the above examples 1-29xCo3-xS4。
Example 30
Will S8Dissolving the simple substance in sodium sulfide water solution to obtain S8Adding CuCo with solid content of 0.3mg/mL into the solution2S4Suspension and S8Mixing the solutions to obtain a mixture; adjusting the pH value of the mixture to 6-7, stirring for 8h, washing and drying to obtain CuCo2S4-S complex, wherein S8The mass ratio of the simple substance to the sodium sulfide is 1: 12.5, the concentration of the sodium sulfide aqueous solution is 1.6mol/L, and the CuCo is2S4CuCo in-S composite2S4The mass ratio of S to S is 1: 4.
example 31
Example 31 differs from example 30 in that,
S8the mass ratio of the simple substance to the sodium sulfide is 1: 15, the concentration of the sodium sulfide aqueous solution is 1.8mol/L, and CuCo is finally obtained2S4-S complex, the CuCo2S4CuCo in-S composite2S4The mass ratio of S to S is 1: 4.5.
example 32
Example 32 differs from example 30 in that,
S8the mass ratio of the simple substance to the sodium sulfide is 1: 13, the concentration of the sodium sulfide aqueous solution is 1.7mol/L, and CuCo is finally obtained2S4-S complex, the CuCo2S4CuCo in-S composite2S4The mass ratio of S to S is 1: 5.
example 33
Example 33 differs from example 30 in that,
CuCo2S4the solid content of the suspension is 0.25mg/mL, the aqueous solution of the sulfide salt is an aqueous solution of ammonium sulfide, S8The mass ratio of the simple substance to the sodium sulfide is 1: 13, the concentration of the aqueous sodium sulfide solution is 1.7mol/L, the mostFinally obtaining CuCo2S4-S complex, the CuCo2S4CuCo in-S composite2S4The mass ratio of S to S is 1: 4.
example 34
Example 34 differs from example 30 in that,
will S8Dissolving the simple substance in sodium sulfide water solution to obtain S8Dissolving in NiCo solution with solid content of 0.3mg/mL2S4Suspension and S8Mixing the solutions to obtain a mixture; adjusting the pH value of the mixture to 6-7, stirring for 8h, washing and drying to obtain NiCo2S4-S complex, wherein S8The mass ratio of the simple substance to the sodium sulfide is 1: 12.5, the concentration of the aqueous solution of sodium sulfide is 1.6mol/L, the NiCo2S4NiCo in-S composite2S4The mass ratio of S to S is 1: 4.
example 35
Example 35 differs from example 30 in that,
will S8Dissolving the simple substance in sodium sulfide water solution to obtain S8Adding MnCo with solid content of 0.3mg/mL into the solution2S4Suspension and S8Mixing the solutions to obtain a mixture; adjusting the pH value of the mixture to 6-7, stirring for 8h, washing and drying to obtain MnCo2S4-S complex, wherein S8The mass ratio of the simple substance to the sodium sulfide is 1: 12.5, the concentration of the aqueous solution of sodium sulfide is 1.6mol/L, the MnCo2S4MnCo in-S composite2S4The mass ratio of S to S is 1: 4.
preparation example of Positive electrode sheet for lithium-Sulfur Battery
MnCo used in the following examples2S4-S complex prepared according to any one of examples 30 to 35.
The obtained MnCo2S4-S complex, acetylene black and polyvinylidene fluoride (PVDF) according to 8: 1:1 in an N-methyl-2-pyrrolidone (NMP) liquid to obtain a slurry. Uniformly coating the slurry on Al foil, placing in a vacuum drying oven at 50 ℃, drying for 24h, and taking out the Al foilRolling under the pressure of 18 MPa. Subsequently, a 12mm diameter positive plate of a lithium-sulfur battery was punched out, a 14mm lithium plate was used as the negative electrode of the battery, and Celgard 2400 was used as the separator, and a CR-2025 button cell was assembled in a glove box filled with Ar. The electrolyte is prepared from ethylene glycol diethyl ether (DME) and 1, 3-Dioxolane (DOL) (the volume ratio of the two is 1: 1)/1.0mol/L lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and 0.2 mol/L-1LiNO of3The mixed solvent of (1).
Comparative example
Preparing a positive pole piece:
sublimed sulfur powder of an active substance, a conductive agent Super-P, a binder polyvinylidene fluoride (PVDF) and a binder are mixed according to the weight ratio of 8: 1:1, in a mass ratio of 1. Firstly, grinding and mixing sulfur powder and Super-P uniformly in a mortar, adding a PVDF solution with the mass fraction of 5%, dropwise adding a proper amount of NMP as a solvent, magnetically stirring for 8 hours, uniformly coating paste-shaped positive electrode slurry on an aluminum foil current collector, then placing in a vacuum drying oven at 50 ℃, and drying for 24 hours.
Assembling the battery:
the Al foil taken out was rolled under a pressure of 18 MPa. Subsequently, an electrode sheet having a diameter of 12mm was punched. A14 mm lithium plate was used as the anode of the cell, the electrode plate prepared in the previous step was used as the cathode, Celgard 2400 was used as the separator, and a CR-2025 button cell was assembled in a glove box filled with Ar. The electrolyte is prepared from ethylene glycol diethyl ether (DME) and 1, 3-Dioxolane (DOL) (the volume ratio of the two is 1: 1)/1.0 mol.L-1Lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and 0.2 mol. L-1LiNO3The mixed solvent of (1).
Electrochemical performance test
M prepared in examples 1 to 29 were each prepared as described abovexCo3-xS4To make a corresponding MxCo3-xS4-S composite material, reuse MxCo3-xS4Preparing the-S composite material into a corresponding positive electrode material of the lithium sulfur battery, assembling the positive electrode material into the battery, adopting a new Wei BTS-5V3A type battery test system produced by New Wille electronics Limited company in Shenzhen City to prepare the lithium sulfur battery of the comparative example, and ensuring that the charging and discharging voltage interval is 1.7The performance of each cell was tested at 2.8V and maintained at 25 c and the test results are listed in table 1.
TABLE 1
Figure BDA0002584320890000141
Figure BDA0002584320890000151
From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects:
due to MxCo3-xS4The material is a sulfide material with a spinel structure, and the delocalized electronic structure of the material enables the material to have higher ionic and electronic conductivity; m of hollow porous nanocubesxCo3-xS4Has high specific surface area (more active sites), if M is usedxCo3-xS4For S loading, on one hand, on the basis that a large amount of S enters a cavity in the hollow porous nanocube through a pore passage on the surface of the hollow porous nanocube, a part of S is adsorbed on the surface of the hollow porous nanocube, so that M is greatly improvedxCo3-xS4Sulfur fixation of (5) to obtain M containing a large amount of SxCo3-xS4-S complex, on the other hand, to mitigate volume expansion associated with charging and discharging; m of simultaneously stronger polarityxCo3-xS4The method is favorable for combination with polysulfide ions to form a TM-S covalent bond, the TM-S covalent bond has strong binding energy and electron transfer capacity, so that effective chemical adsorption and conversion of polysulfide are favorably realized, and then the catalytic conversion of polysulfide is performed by bimetal (M and Co) with multiple valences, so that the shuttle effect of polysulfide ions is greatly reduced, the theoretical capacity of the positive electrode material of the lithium-sulfur battery is improved, and the rate capability and the cycle performance of the lithium-sulfur battery are improved.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (12)

1. A bimetallic sulfide characterized by the chemical formula MxCo3-xS4M is selected from any one of Ni, Cu, Mn, V, Fe, Zn and Mo, the shape of the bimetal sulfide is a hollow porous nanocube structure, wherein x is more than or equal to 0.5 and less than or equal to 1.5.
2. The bimetallic sulfide of claim 1, wherein the porous nanocube-shaped edge length is 450 to 550nm, the pore size of the bimetallic sulfide is preferably 2 to 6nm, and the specific surface area of the bimetallic sulfide is preferably 25 to 40m2/g。
3. The process for the preparation of bimetallic sulfide as claimed in claim 1 or 2, characterized in that it comprises:
step S1, performing acid solution treatment on MxCo3-x[Co(CN)6]2Etching the precursor to obtain a hollow MxCo3-x[Co(CN)6]2；
Step S2, making the hollow MxCo3-x[Co(CN)6]2Calcining to obtain the bimetallic sulfide, wherein the calcining is carried out in the presence of H2S, preferably said H-containing gas2The gas of S is H2S and N2Or a mixture comprising H2S and inert gas.
4. The manufacturing method according to claim 3, wherein the etching process includes:
mixing the acid solution, surfactant, the MxCo3-x[Co(CN)6]2And after mixing the precursors, carrying out the etching treatment, preferably selecting the surfactant from polyvinylpyrrolidone or cetyl trimethyl ammonium bromide, selecting the hydrogen ion concentration in the acid solution to be 1-5 mol/L, preferably selecting the acid solution from one or more of hydrochloric acid, nitric acid aqueous solution and sulfuric acid aqueous solution, preferably selecting the MxCo3-x[Co(CN)6]2The mass ratio of the precursor to the surfactant is 1: 5-1: 7, and the etching treatment temperature is preferably 140-200 ℃.
5. The production method according to claim 3, wherein M is calculated as hydrogen ionsxCo3-x[Co(CN)6]2The molar ratio of the precursor to the acid solution is 1:2 × 104～1:10×104。
6. The method of claim 3, wherein the H is2S and the hollow MxCo3-x[Co(CN)6]2Is 4:1 to 8:1, preferably the H in the mixed gas2The volume fraction of S is 5-15%.
7. The method of claim 3, wherein the calcining comprises:
making the hollow MxCo3-x[Co(CN)6]2Heating to 350-400 ℃ in the mixed gas at a speed of 2-5 ℃/min to obtain a calcined intermediate, and preferably, the calcining time is 3-5 h;
and cooling the calcined intermediate in the mixed gas at the speed of 2-5 ℃/min to 20-25 ℃ to obtain the bimetallic sulfide.
8. A complex, wherein said complex is MxCo3-xS4-S complex at said MxCo3-xS4-M in S ComplexxCo3-xS4The mass ratio of S to S is 1: 4 to 5.
9. A method of preparing the composite of claim 8, comprising:
will MxCo3-xS4Suspension and S8Mixing the solutions to obtain a mixture;
and adjusting the pH value of the mixture to 6-7, stirring, washing and drying to obtain the compound, wherein the stirring time is preferably 8-10 h.
10. The method of claim 9, wherein M isxCo3-xS4The solid content of the suspension is 0.25-0.3 mg/mL, and the S is preferably selected8Solution of S8The simple substance is dissolved in the aqueous solution of sulfide salt, preferably the S8The mass ratio of the simple substance to the sulfide salt is 1: 12.5-15, preferably the concentration of the sulfide salt water solution is 1.6-1.8 mol/L, and the sulfide salt water solution is selected from one or more of sodium sulfide water solution, potassium sulfide water solution and ammonium sulfide water solution.
11. A lithium sulfur positive electrode material comprising a sulfur-containing composite, wherein the sulfur-containing composite is the composite according to claim 8.
12. A lithium-sulfur battery comprising a positive electrode and a negative electrode, wherein the positive electrode is the lithium-sulfur positive electrode material according to claim 11.
CN202010676740.2A 2020-07-14 2020-07-14 Bimetal sulfide and preparation method thereof, compound and preparation method thereof, lithium-sulfur positive electrode material and lithium-sulfur battery Pending CN111933904A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113206235A (en) * 2021-04-30 2021-08-03 陕西科技大学 Multi-component (V, Zn) metal sulfide and preparation method thereof
CN114843117A (en) * 2022-04-18 2022-08-02 湖南防灾科技有限公司 Metal sulfide energy storage electrode and preparation method and application thereof
CN114853075A (en) * 2022-04-25 2022-08-05 多助科技(武汉)有限公司 Mn-doped FeS/CN bimetallic sulfide material with large lattice spacing as well as preparation method and application thereof

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113206235A (en) * 2021-04-30 2021-08-03 陕西科技大学 Multi-component (V, Zn) metal sulfide and preparation method thereof
CN113206235B (en) * 2021-04-30 2022-11-18 陕西科技大学 Multi-component (V, zn) metal sulfide and preparation method thereof
CN114843117A (en) * 2022-04-18 2022-08-02 湖南防灾科技有限公司 Metal sulfide energy storage electrode and preparation method and application thereof
CN114853075A (en) * 2022-04-25 2022-08-05 多助科技(武汉)有限公司 Mn-doped FeS/CN bimetallic sulfide material with large lattice spacing as well as preparation method and application thereof

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