CN114162874B - Preparation method of composite metal sulfide loaded mixed carbon material serving as sulfur main body material of lithium-sulfur battery - Google Patents

Preparation method of composite metal sulfide loaded mixed carbon material serving as sulfur main body material of lithium-sulfur battery Download PDF

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CN114162874B
CN114162874B CN202111499654.XA CN202111499654A CN114162874B CN 114162874 B CN114162874 B CN 114162874B CN 202111499654 A CN202111499654 A CN 202111499654A CN 114162874 B CN114162874 B CN 114162874B
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曹瑞国
杨善
焦淑红
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University of Science and Technology of China USTC
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Abstract

The invention discloses a preparation method of a mixed carbon material loaded with a composite metal sulfide as a sulfur main body material of a lithium-sulfur battery. The microstructure of the sulfur main body material of the lithium-sulfur battery contains a stable continuous conductive network, transition metal sulfides with good adsorption and catalytic performances grow in situ on the surface of the sulfur main body material, and the transition metal sulfides are distributed uniformly, so that the sulfur main body material has good conductivity, the utilization rate of sulfur is improved, the loss of sulfur-containing substances in the charge-discharge cycle process of the battery can be effectively reduced, and the long cycle stability of the lithium-sulfur battery is finally improved; meanwhile, the preparation process of the sulfur main body material of the lithium-sulfur battery is simple and has good universality.

Description

Preparation method of composite metal sulfide loaded mixed carbon material serving as sulfur main body material of lithium-sulfur battery
Technical Field
The invention belongs to the technical field of new materials, and particularly relates to a preparation method of a sulfur main body material of a lithium-sulfur battery.
Background
In order to improve the comprehensive performance of the secondary battery to meet the increasing application of the secondary battery in real life, it is urgent to develop a brand new secondary battery system in addition to further upgrade the traditional lithium ion battery. The lithium-sulfur battery takes lithium metal as a negative electrode and elemental sulfur as a positive electrode, and takes reaction Li + S = Li 2 The secondary battery system which can be charged and discharged circularly based on S has the advantages of high theoretical energy density, rich sulfur storage in the earth crust, no pollution to the environment and the like, so the secondary battery system becomes the key point of research of researchers. Since sulfur itself has poor conductivity and a large volume change during charge and discharge, it is necessary to use a positive electrode material having good physicochemical properties as a main body for supporting sulfur to effectively improve the long cycle performance of the lithium-sulfur battery.
The carbon material is suitable for being used as a sulfur main body material of a lithium sulfur battery due to the advantages of rich pore structure, large specific surface area, good conductivity and the like. Various carbon materials have been used as sulfur host materials for lithium-sulfur batteries, such as carbon fibers, carbon nanotubes, graphene, MXene, and hollow carbon spheres, and all of them have achieved certain effects. However, the performance improvement of a single kind of carbon material used as a sulfur main body material of a lithium sulfur battery is still relatively limited, so researchers currently try to uniformly mix carbon materials with multiple dimensions according to a certain mass ratio to construct a multi-dimensional mixed carbon material system, which has a more stable conductive network, a richer pore structure and a larger specific surface area, so that more active substances can be supported and the utilization rate of sulfur in a long-cycle process can be improved, and the combination of a one-dimensional carbon material and a two-dimensional carbon material has good development potential.
Since the carbon material itself has no polarity and the carbon material itself has no catalytic activity, it is necessary to introduce certain metal compounds (e.g., metal oxides, metal sulfides, metal nitrides, etc.) into the sulfur host material of the lithium sulfur battery in order to effectively promote the kinetics of polysulfide conversion in the lithium sulfur battery reaction, and they are used as an adsorbent and a catalyst for polysulfide. The transition metal element has good catalytic activity due to its unique electronic structure, so the transition metal sulfide can be used as a catalyst for polysulfide in the sulfur host material of the lithium sulfur battery. VS 4 Is a linear transition metal sulfide with good conductivity, wherein adjacent V 4+ (S 2 2- ) 2 The chains are bonded by weak van der Waals force, so that the rapid charge transfer kinetics of the chains can be promoted, and the catalytic activity is good, and the specific layer type VS is also realized 2 Stronger adsorption capacity to polysulfide. At the same time, iron sulfide (e.g. FeS, feS) 2 Etc.) has an excellent adsorption function for polysulfides. Thus, turn VS 4 And iron sulfide (FeS) x ) Both are feasible to incorporate into the sulfur host material of a lithium sulfur battery as an adsorbent and catalyst for polysulfides.
At present, a single carbon material is used as a sulfur main body material of a lithium sulfur battery, but a mixed multi-dimensional carbon material structure formed by combining carbon materials with different dimensions is less applied to the sulfur main body material of the lithium sulfur battery, and a composite sulfide composed of two transition metal sulfides is not grown in situ on the mixed multi-dimensional carbon material structure to be used as the sulfur main body material of the lithium sulfur battery.
Disclosure of Invention
The invention aims to provide a preparation method of a carbon fiber and graphene mixed carbon material loaded with iron sulfide and vanadium tetrasulfide composite metal sulfide, which is used as a sulfur main body material of a lithium-sulfur battery, so that the problems of poor conductivity of sulfur in the lithium-sulfur battery and serious polysulfide loss in a long circulation process are solved, the long circulation performance of the lithium-sulfur battery is effectively improved, and the practical application of the lithium-sulfur battery is promoted.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a composite metal sulfide loaded mixed carbon material used as a sulfur main body material of a lithium-sulfur battery comprises the following steps:
1) Slowly adding concentrated sulfuric acid into concentrated nitric acid to obtain a strong acid mixed solution; adding carbon fiber into the strong acid mixed solution, and performing reflux reaction under the condition of oil bath to obtain carbon fiber CNFO subjected to acidification treatment;
2) Uniformly mixing the CNFO obtained in the step 1) with graphene oxide powder to obtain a mixed carbon material;
3) Na is mixed with 3 VO 4 Sequentially dissolving TAA (thioacetamide) and CTAB (cetyl trimethyl ammonium bromide) in deionized water, and fully stirring to obtain a clear solution A; adding the mixed carbon material prepared in the step 2) into the solution A, and uniformly stirring after ultrasonic dispersion to obtain a suspension B;
4) Carrying out hydrothermal reaction on the suspension B, and obtaining an intermediate after the reaction is finished;
5) Weighing a certain amount of FeSO 4 ·7H 2 Adding O into deionized water, and fully stirring and dissolving to obtain a uniform solution C;
6) Adding the intermediate prepared in the step 4) into a mixed solution of deionized water and absolute ethyl alcohol, and uniformly stirring after ultrasonic dispersion to form a suspension D;
7) Slowly adding the solution C into the suspension D under the condition of continuous stirring, and then fully stirring to obtain a suspension E; carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying to obtain a dry precursor;
8) Flatly paving the precursor obtained in the step 7) in a corundum square boat, placing the square boat in a tubular furnace, heating in argon atmosphere for reaction, cooling to room temperature in argon atmosphere after the reaction is finished, and obtaining the carbon fiber and graphene mixed carbon material loaded with iron sulfide and vanadium tetrasulfide composite metal sulfide as the sulfur main material of the lithium-sulfur battery, wherein the carbon fiber and graphene mixed carbon material is recorded as FeS x -VS 4 @(rGO+CNF)。
Preferably, in the step 1), 25mL to 37.5mL of concentrated nitric acid is added into every 12.5mL to 75mL of concentrated sulfuric acid, 250mg to 1000mg of carbon fiber is added into every 37.5mL to 112.5mL of strong acid mixed solution, the temperature of the reflux reaction is controlled to be 75 ℃ to 85 ℃, and the reaction time is controlled to be 2h to 4h.
Preferably, in the step 2), the mass ratio of the graphene oxide powder to the CNFO is 90mg to 100mg:100mg to 110mg.
Preferably, 165-185 mg of Na is added into every 20-25 mL of deionized water in the step 3) 3 VO 4 650-750 mg of TAA and 100-120 mg of CTAB, and 190-210 mg of the mixed carbon material is added into each 20-25 mL of the solution A.
Preferably, step 4), the hydrothermal reaction is specifically: adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 50-60%, placing into an electric constant-temperature air-blast drying oven, controlling the reaction temperature to be 155-165 ℃ and controlling the reaction time to be 22-26 h.
Preferably, in the step 5), 680mg to 720mg of FeSO is added into every 45mL to 55mL of deionized water 4 ·7H 2 O。
Preferably, in the step 6), 20mL to 30mL of anhydrous ethanol is added into every 20mL to 30mL of deionized water, and 100mg to 120mg of intermediate is added into every 40mL to 60mL of mixed solution.
Preferably, in step 7), the solution C is slowly added to the suspension D, and then stirred for 2 to 4 hours, and the temperature for drying the wet precursor is 80 ℃.
Preferably, in the step 8), the temperature rise reaction is carried out at a temperature rise rate of 3-5 ℃/min to 250-350 ℃, and the heat preservation treatment is carried out for 1-3 h.
The mixed carbon material loaded with the composite metal sulfide prepared by the invention can be used as a sulfur main body material of a lithium-sulfur battery.
Compared with the prior art, the invention has the beneficial effects that:
1) The sulfur main body material of the lithium-sulfur battery utilizes a mixed carbon material structure composed of one-dimensional carbon fibers and two-dimensional graphene, has a continuous conductive network with a more stable microstructure, and is beneficial to reducing the impedance of the battery; and the porous structure is richer, the specific surface area is larger, and the sulfur carrying capacity is stronger.
2) The sulfur main body material of the lithium-sulfur battery prepared by the invention comprises FeS x And VS 4 Complexes of two transition metal sulfides, feS x And VS 4 Each can act as an adsorbent and catalyst to effectively adsorb polysulfides and promote the kinetics of polysulfide conversion reactions, thereby minimizing loss of active species during long cycles; at the same time, feS x And VS 4 The formed composite sulfide also has a good synergistic effect, can more efficiently complete the adsorption and catalysis of polysulfide, and further improves the utilization rate of sulfur in the long-cycle process.
3) The FeS-based carbon material grows on the surface of a mixed carbon material structure composed of one-dimensional carbon fibers and two-dimensional graphene in situ x And VS 4 The composite metal sulfide successfully combines the advantages of the mixed carbon material structure with the advantages of the composite metal sulfide, thereby comprehensively solving the defects of the sulfur main body material of the lithium sulfur battery only containing a single carbon material or a single metal compound adsorption-catalyst in the prior art and effectively improving the long cycle performance of the lithium sulfur battery.
4) FeS prepared by the invention x -VS 4 After the sulfur main body material of the @ lithium sulfur battery (rGO + CNF) bears sulfur by a melt diffusion method, a corresponding positive pole piece is prepared and a lithium sulfur full battery is assembled for testing, the charging and discharging performance is excellent, and the multiplying power of the battery is 0.2CThe first discharge specific capacity can reach 1164.6mAh/g; after 50 charge-discharge cycles, the discharge specific capacity is still maintained at 898.7mAh/g, and the long-cycle stability is excellent.
5) The preparation process is simple and has good universality.
Drawings
FIG. 1 is a FeS prepared according to example 1 of the present invention x -VS 4 The X-ray diffraction pattern of the @ material (rGO + CNF);
FIG. 2 is a FeS prepared according to example 1 of the present invention x -VS 4 Raman spectra for the @ material (rGO + CNF);
FIGS. 3A and 3B show FeS prepared in example 1 of the present invention x -VS 4 Scanning electron micrographs of the @ material (rGO + CNF) at different magnifications;
FIG. 4 is FeS prepared according to example 1 of the present invention x -VS 4 A graph of the change of specific discharge capacity along with cycle times is obtained by testing after the @ material bears sulfur;
FIG. 5 is FeS prepared according to example 2 of the present invention x -VS 4 The X-ray diffraction pattern of the @ material (rGO + CNF);
FIG. 6 is FeS prepared according to example 2 of the present invention x -VS 4 Raman spectra for the @ material (rGO + CNF);
FIG. 7 is FeS prepared according to example 2 of the present invention x -VS 4 Scanning electron microscopy of the @ material (rGO + CNF);
FIG. 8 is a FeS product prepared in example 3 of the present invention x -VS 4 The X-ray diffraction pattern of the @ material (rGO + CNF);
FIG. 9 is FeS prepared according to example 3 of the present invention x -VS 4 Raman spectra of @ material (rGO + CNF);
FIG. 10 is a FeS prepared according to example 3 of the present invention x -VS 4 Scanning electron microscopy of the @ material (rGO + CNF).
Detailed Description
Embodiments of the invention are described in further detail below:
the invention discloses a preparation method of a mixed carbon material loaded with composite metal sulfide as a sulfur main body material of a lithium-sulfur battery, which comprises the following steps:
1) Slowly adding 12.5-75 mL of concentrated sulfuric acid into 25-37.5 mL of concentrated nitric acid, adding carbon fiber into the strong acid mixed solution, adding 250-1000 mg of carbon fiber into each 37.5-112.5 mL of strong acid mixed solution, and performing reflux reaction for 2-4 h under the condition of oil bath at 75-85 ℃ to obtain the acidified carbon fiber (CNFO).
2) Uniformly mixing 100-110 mg of CNFO obtained in the step 1) with 90-100 mg of graphene oxide powder to obtain the mixed carbon material.
3) 165-185 mgNa 3 VO 4 650 mg-750 mg TAA and 100 mg-120 mg CTAB are dissolved in 20 mL-25 mL deionized water in sequence, and a clear solution A is obtained after full stirring; and then adding 190-210 mg of the mixed carbon material prepared in the step 2) into 20-25 mL of the solution A, and stirring uniformly after ultrasonic dispersion to obtain a suspension B.
4) And adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 50-60%, then putting the suspension B into an electric constant-temperature air-blast drying oven, carrying out hydrothermal reaction for 22-26 h at the reaction temperature of 155-165 ℃, and obtaining an intermediate after the reaction is finished.
5) Weighing 680-720 mg of FeSO 4 ·7H 2 Adding O into 45-55 mL of deionized water, and fully stirring and dissolving to obtain a uniform solution C.
6) Adding the intermediate prepared in the step 4) into a mixed solution of 20-30 mL of deionized water and 20-30 mL of absolute ethyl alcohol, adding 100-120 mg of the intermediate into every 40-60 mL of the mixed solution, performing ultrasonic dispersion, and uniformly stirring to form a suspension D.
7) Slowly adding the solution C into the suspension D under the condition of continuous stirring, and then fully stirring for 2-4 h to obtain fully mixed suspension E; and carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying the wet precursor at the temperature of 80 ℃ to obtain a dried precursor.
8) Spreading the precursor obtained in the step 7) on a steel frameIn the jade square boat, the square boat is placed in a tube furnace, the temperature is raised to 250-350 ℃ in the argon atmosphere at the speed of 3-5 ℃/min, the heat is preserved for 1-3 h, the square boat is cooled to room temperature in the argon atmosphere after the reaction is finished, and finally FeS is obtained x -VS 4 The host material of the @ lithium sulfur battery sulfur is rGO + CNF.
The present invention is described in further detail below with reference to specific examples:
example 1
1) 75mL of concentrated sulfuric acid was slowly added to 25mL of concentrated nitric acid, 1000mg of carbon fiber was added to the strong acid mixed solution, and then a reflux reaction was performed for 3 hours under an oil bath condition at 80 ℃ to obtain an acidified carbon fiber (CNFO).
2) Uniformly mixing 100mg of the CNFO obtained in step 1) with 100mg of graphene oxide powder to obtain a mixed carbon material.
3) Adding 175mgNa 3 VO 4 700mgTAA and 110mgCTAB are dissolved in 22.5mL deionized water in sequence, and a clear solution A is obtained after full stirring; and then adding 200mg of the mixed carbon material prepared in the step 2) into 22.5mL of the solution A, and uniformly stirring after ultrasonic dispersion to obtain a suspension B.
4) And adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 55%, then placing the hydrothermal reaction kettle into an electric constant-temperature air-blast drying oven, carrying out hydrothermal reaction for 24 hours at the reaction temperature of 160 ℃, and obtaining an intermediate after the reaction is finished.
5) 700mg of FeSO are weighed 4 ·7H 2 And adding O into 50mL of deionized water, and fully stirring and dissolving to obtain a uniform solution C.
6) Adding 110mg of the intermediate prepared in the step 4) into a mixed solution of 25mL of deionized water and 25mL of absolute ethyl alcohol, and uniformly stirring after ultrasonic dispersion to form a suspension D.
7) Slowly adding the solution C to the suspension D under continuous stirring, followed by stirring thoroughly for 3h to obtain a well-mixed suspension E; and carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying the wet precursor at the temperature of 80 ℃ to obtain a dried precursor.
8) In step 7)The obtained precursor is spread in a corundum ark, the ark is placed in a tube furnace and is heated to 300 ℃ at the speed of 4 ℃/min in the argon atmosphere, then the temperature is kept for 2h, and after the reaction is finished, the ark is cooled to room temperature in the argon atmosphere, and finally FeS is obtained x -VS 4 The host material of the lithium sulfur battery is @ (rGO + CNF).
To test the electrochemical performance of the sulfur host material of the lithium sulfur battery obtained in this example, a battery was assembled and subjected to electrochemical testing as follows: uniformly mixing the sulfur main body material of the lithium-sulfur battery synthesized in the embodiment with sulfur powder according to a mass ratio of 3:7, spreading the obtained mixture powder in a corundum ark, placing the ark in a forced air drying oven, heating to 155 ℃ in air atmosphere, then preserving heat for 12 hours, and cooling to room temperature after heat preservation is finished, thereby obtaining FeS loaded with sulfur prepared by a melt diffusion method x -VS 4 @ S (rGO + CNF) Sulfur host Material (i.e., S/FeS) x -VS 4 @ (rGO + CNF) cathode material); then the S/FeS is added x -VS 4 The effective mass ratio of the @ (rGO + CNF) anode material to the carbon nano tube, the sodium carboxymethyl cellulose (CMC) and the Styrene Butadiene Rubber (SBR) is 8:1.5:0.25:0.25 of the slurry is prepared and coated on the carbon-coated aluminum foil to prepare a positive pole piece; 1.0mol/LLITFSI and 0.1mol/L LiNO dissolved in 1,3-Dioxolane (DOL) and ethylene glycol dimethyl ether (DME) (the volume ratio is 1:1) 3 Is an electrolyte; a polypropylene (PP) single-layer film is used as a diaphragm, and the diaphragm is assembled into a CR2032 type button battery in an argon glove box. A LAND-CT-2001A test system is adopted to carry out multiplying power charge and discharge test at the multiplying power of 0.2C within the voltage range of 1.7-2.8V at the temperature of 25 ℃.
FIG. 1 shows FeS prepared in this example x -VS 4 X-ray diffraction pattern of the @ material rGO + CNF. As can be seen from fig. 1, the diffraction peaks other than 2 θ =26.2 ° correspond to the carbon material in the sulfur host material, and all of the other diffraction peaks correspond to VS 4 Corresponding to the PDF standard card (87-0603), it shows that VS exists in the sulfur main body material of the lithium-sulfur battery prepared in the embodiment 4
FIG. 2 shows FeS prepared in this example x -VS 4 Raman spectra of the @ material (rGO + CNF). As can be seen from FIG. 2, the sulfur host material for the lithium sulfur battery prepared in this exampleNot only does there exist a VS 4 Also the presence of FeS x
FIGS. 3A and 3B show FeS prepared in this example x -VS 4 Scanning electron microscope images of the sulfur main material of the @ lithium sulfur battery (rGO + CNF) at different magnifications. As can be seen from fig. 3A and 3B, the mixed carbon structure material composed of carbon fibers and graphene has a continuous conductive network which is interwoven with each other, transition metal sulfides are grown in situ on the surface of the mixed carbon structure material, and the distribution is relatively uniform. From the above results, the sulfur host material of the lithium sulfur battery prepared in this example was FeS x -VS 4 @(rGO+CNF)。
FIG. 4 shows FeS prepared in this example x -VS 4 The graph of specific discharge capacity as a function of cycle number is obtained after carrying sulfur by a melting diffusion method for the material of @ (@ (rGO + CNF). As can be seen from FIG. 4, the FeS prepared in this example x -VS 4 After the material of @ (@ (rGO + CNF) bears sulfur, the charge and discharge performance of the corresponding full battery is excellent, the initial discharge specific capacity of the material under the multiplying power of 0.2C can reach 1164.6mAh/g, and after 50 charge and discharge cycles, the discharge specific capacity can still be kept at 898.7mAh/g. Thus, feS was found x -VS 4 The electrochemical performance of the @ (rGO + CNF) lithium sulfur battery sulfur main body material is good, and the @ lithium sulfur battery sulfur main body material has excellent long cycle stability.
Example 2
1) 12.5mL of concentrated sulfuric acid was slowly added to 37.5mL of concentrated nitric acid, and 250mg of carbon fiber was added to the strong acid mixed solution, followed by reflux reaction at 75 ℃ for 2 hours in an oil bath to obtain acidified carbon fiber (CNFO).
2) Uniformly mixing 110mg of the CNFO obtained in step 1) with 90mg of graphene oxide powder to obtain a mixed carbon material.
3) 165mgNa 3 VO 4 650mgTAA and 100mgCTAB are dissolved in 20mL deionized water in sequence, and a clear solution A is obtained after full stirring; then 190mg of the mixed carbon material prepared in step 2) was added to 20mL of the solution a, and the mixture was ultrasonically dispersed and stirred to obtain a suspension B.
4) And adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 50%, then placing the suspension B into an electric constant-temperature air-blast drying oven, carrying out hydrothermal reaction for 22h at the reaction temperature of 155 ℃, and obtaining an intermediate after the reaction is finished.
5) 680mg of FeSO are weighed 4 ·7H 2 And adding O into 45mL of deionized water, and fully stirring and dissolving to obtain a uniform solution C.
6) Adding 100mg of the intermediate prepared in the step 4) into a mixed solution of 20mL of deionized water and 20mL of absolute ethyl alcohol, and uniformly stirring after ultrasonic dispersion to form a suspension D.
7) Slowly adding the solution C to the suspension D under continuous stirring, followed by stirring thoroughly for 2h to obtain a well-mixed suspension E; and carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying the wet precursor at the temperature of 80 ℃ to obtain a dried precursor.
8) Flatly paving the precursor obtained in the step 7) in a corundum square boat, putting the square boat in a tube furnace, heating to 250 ℃ at the speed of 3 ℃/min in an argon atmosphere, then preserving heat for 1h, cooling to room temperature in the argon atmosphere after the reaction is finished, and finally obtaining FeS x -VS 4 The host material of the lithium sulfur battery is @ (rGO + CNF).
FIG. 5 shows FeS prepared in this example x -VS 4 X-ray diffraction pattern of the @ material (rGO + CNF). As can be seen from fig. 5, the diffraction peaks other than 2 θ =26.2 ° correspond to the carbon material in the sulfur host material, and all of the other diffraction peaks correspond to VS 4 The corresponding PDF standard card (87-0603) shows that the sulfur main body material of the lithium-sulfur battery prepared in the embodiment contains VS 4
FIG. 6 shows FeS prepared in this example x -VS 4 Raman spectra of the @ material (rGO + CNF). As can be seen from fig. 6, iron sulfide (FeS) is also present in the sulfur host material of the lithium sulfur battery prepared in this example x )。
FIG. 7 shows FeS prepared in this example x -VS 4 Scanning electron microscopy of the @ material (rGO + CNF). As can be seen from FIG. 7, the mixed carbon structure material composed of carbon fiber and graphene has a stable continuous conductive network on the surface thereofTransition metal sulfide with uniform distribution is grown in the position. From the above results, the sulfur host material of the lithium sulfur battery prepared in this example is FeS x -VS 4 @(rGO+CNF)。
Example 3
1) 50mL of concentrated sulfuric acid was slowly added to 25mL of concentrated nitric acid, and 750mg of carbon fiber was added to the strong acid mixed solution, followed by a reflux reaction at 85 ℃ for 4 hours in an oil bath to obtain an acidified carbon fiber (CNFO).
2) 105mg of the CNFO obtained in step 1) was uniformly mixed with 95mg of graphene oxide powder to obtain a mixed carbon material.
3) 185mgNa 3 VO 4 750mgTAA and 120mgCTAB are dissolved in 25mL deionized water in sequence, and a clear solution A is obtained after full stirring; and then adding 210mg of the mixed carbon material prepared in the step 2) into 25mL of the solution A, performing ultrasonic dispersion, and uniformly stirring to obtain a suspension B.
4) And adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 60%, then putting the suspension B into an electric constant-temperature air-blowing drying box, carrying out hydrothermal reaction for 26 hours at the reaction temperature of 165 ℃, and obtaining an intermediate after the reaction is finished.
5) 720mg of FeSO are weighed out 4 ·7H 2 And adding O into 55mL of deionized water, and fully stirring and dissolving to obtain a uniform solution C.
6) 120mg of the intermediate prepared in step 4) was added to a mixed solution of 30mL of deionized water and 30mL of anhydrous ethanol, and stirred for a certain period of time after ultrasonic dispersion to form a suspension D.
7) Slowly adding solution C to suspension D with constant stirring, followed by stirring well for 4h to obtain well-mixed suspension E; carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying the wet precursor at the temperature of 80 ℃ to obtain a dried precursor;
8) Flatly paving the precursor obtained in the step 7) in a corundum square boat, putting the square boat in a tube furnace, heating to 350 ℃ at the speed of 5 ℃/min in an argon atmosphere, then preserving heat for 3h, cooling to room temperature in the argon atmosphere after the reaction is finished, and finally obtaining the corundum square boatTo FeS x -VS 4 The host material of the @ lithium sulfur battery sulfur is rGO + CNF.
FIG. 8 shows FeS prepared in this example x -VS 4 X-ray diffraction pattern of the @ material (rGO + CNF). As can be seen from fig. 8, the diffraction peaks other than 2 θ =26.2 ° correspond to the carbon material in the sulfur host material, and all of the diffraction peaks are associated with VS 4 Corresponding to the standard PDF card (87-0603), it is shown that the sulfur main body material of the lithium-sulfur battery prepared in the embodiment also contains VS 4
FIG. 9 shows FeS prepared in this example x -VS 4 Raman spectra of the @ material (rGO + CNF). As can be seen from FIG. 9, the sulfur host material for the lithium-sulfur battery prepared in this example contains VS 4 While also containing FeS x
FIG. 10 shows FeS prepared in this example x -VS 4 Scanning electron microscopy of the @ material (rGO + CNF). As can be seen from fig. 10, the mixed carbon structure material composed of carbon fiber and graphene has a stable continuous conductive network, on the surface of which transition metal sulfide is grown in situ and distributed uniformly. From the above results, it can be seen that the sulfur host material for the lithium-sulfur battery prepared in this example is also FeS x -VS 4 @(rGO+CNF)。
The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (6)

1. A preparation method of a composite metal sulfide-loaded mixed carbon material used as a sulfur main body material of a lithium-sulfur battery is characterized by comprising the following steps:
1) Slowly adding concentrated sulfuric acid into concentrated nitric acid to obtain a strong acid mixed solution; adding carbon fibers into the strong acid mixed solution, and performing reflux reaction under the condition of an oil bath to obtain carbon fiber CNFO subjected to acidification treatment; wherein 25mL to 37.5mL of concentrated nitric acid is added into 12.5mL to 75mL of concentrated sulfuric acid, 250mg to 1000mg of carbon fiber is added into 37.5mL to 112.5mL of strong acid mixed solution, the temperature of the reflux reaction is controlled to be 75 ℃ to 85 ℃, and the reaction time is controlled to be 2h to 4h;
2) Uniformly mixing the CNFO obtained in the step 1) with graphene oxide powder to obtain a mixed carbon material, wherein the mass ratio of the graphene oxide powder to the CNFO is 90-100 mg:100mg to 110mg;
3) Mixing Na 3 VO 4 Sequentially dissolving TAA and CTAB in deionized water, and fully stirring to obtain a clear solution A; adding the mixed carbon material prepared in the step 2) into the solution A, and uniformly stirring after ultrasonic dispersion to obtain a suspension B; wherein, 165mg to 185mg of Na is added into each 20mL to 25mL of deionized water 3 VO 4 650-750 mg of TAA and 100-120 mg of CTAB, and 190-210 mg of mixed carbon material is added into every 20-25 mL of solution A;
4) Carrying out hydrothermal reaction on the suspension B, and obtaining an intermediate after the reaction is finished;
5) Weighing a certain amount of FeSO 4 ·7H 2 Adding O into deionized water, and fully stirring and dissolving to obtain a uniform solution C; wherein, every 45mL to 55mL of deionized water is added with 680mg to 720mg of FeSO 4 ·7H 2 O;
6) Adding the intermediate prepared in the step 4) into a mixed solution of deionized water and absolute ethyl alcohol, and uniformly stirring after ultrasonic dispersion to form a suspension D;
7) Slowly adding the solution C into the suspension D under the condition of continuous stirring, and then fully stirring to obtain a suspension E; carrying out suction filtration on the suspension E to obtain a wet precursor on filter paper, and then drying to obtain a dry precursor;
8) Flatly paving the precursor obtained in the step 7) in a corundum ark, placing the ark in a tubular furnace, heating in an argon atmosphere for reaction, and cooling to room temperature in the argon atmosphere after the reaction is finished to obtain a carbon fiber and graphene mixed carbon material loaded with iron sulfide and vanadium tetrasulfide composite metal sulfide as a sulfur main material of a lithium-sulfur battery, and marking the carbon fiber and graphene mixed carbon material as FeS x -VS 4 @(rGO+CNF)。
2. The method for preparing a mixed carbon material loaded with a complex metal sulfide as a sulfur host material for a lithium sulfur battery according to claim 1, wherein: step 4), the hydrothermal reaction is specifically as follows: and adding the suspension B into a hydrothermal reaction kettle, sealing, controlling the filling ratio to be 50-60%, placing into an electric constant-temperature air blowing drying box, controlling the reaction temperature to be 155-165 ℃ and controlling the reaction time to be 22-26 h.
3. The method for producing a composite metal sulfide-loaded mixed carbon material as a sulfur host material for a lithium sulfur battery according to claim 1, wherein: in the step 6), 20mL to 30mL of absolute ethyl alcohol is added into every 20mL to 30mL of deionized water, and 100mg to 120mg of intermediate is added into every 40mL to 60mL of mixed solution.
4. The method for producing a composite metal sulfide-loaded mixed carbon material as a sulfur host material for a lithium sulfur battery according to claim 1, wherein: in the step 7), the solution C is slowly added into the suspension D, then the stirring time is in the range of 2-4 h, and the temperature for drying the wet precursor is 80 ℃.
5. The method for producing a composite metal sulfide-loaded mixed carbon material as a sulfur host material for a lithium sulfur battery according to claim 1, wherein: in the step 8), the temperature rise reaction is carried out at the temperature rise rate of 3-5 ℃/min to 250-350 ℃, and the heat preservation treatment is carried out for 1-3 h.
6. A mixed carbon material carrying a composite metal sulfide, which is obtained by the production method according to any one of claims 1 to 5.
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140117189A (en) * 2013-03-26 2014-10-07 국립대학법인 울산과학기술대학교 산학협력단 Synthesis method of hybrid consisting of vanadium sulfide and reduced graphite oxide and lithium ion battery comprising the hybrid
CN109585828A (en) * 2018-11-29 2019-04-05 济南大学 RGO/VS is prepared in situ in one-step method4/ S compound is as lithium sulfur battery anode material
CN109888223A (en) * 2019-02-26 2019-06-14 陕西科技大学 A kind of preparation method and application of four vanadic sulfides@redox graphene composite granule
CN112490438A (en) * 2020-11-27 2021-03-12 青岛科技大学 Magnesium ion battery positive electrode material Mo-VS4N-GNTs and uses thereof
CN113130863A (en) * 2021-03-22 2021-07-16 郑州大学 VS (virtual switch)4/rGO composite material, preparation method thereof and application in zinc ion battery

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20140117189A (en) * 2013-03-26 2014-10-07 국립대학법인 울산과학기술대학교 산학협력단 Synthesis method of hybrid consisting of vanadium sulfide and reduced graphite oxide and lithium ion battery comprising the hybrid
CN109585828A (en) * 2018-11-29 2019-04-05 济南大学 RGO/VS is prepared in situ in one-step method4/ S compound is as lithium sulfur battery anode material
CN109888223A (en) * 2019-02-26 2019-06-14 陕西科技大学 A kind of preparation method and application of four vanadic sulfides@redox graphene composite granule
CN112490438A (en) * 2020-11-27 2021-03-12 青岛科技大学 Magnesium ion battery positive electrode material Mo-VS4N-GNTs and uses thereof
CN113130863A (en) * 2021-03-22 2021-07-16 郑州大学 VS (virtual switch)4/rGO composite material, preparation method thereof and application in zinc ion battery

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
"石墨烯改性锂硫电池正极材料的制备及其电化学性能研究";卢松涛;《中国优秀博硕士学位论文全文数据库(博士)工程科技Ⅱ辑》;20141215;第57页 *
"纳米 Fe@C和 FeSx改性对VS4/RGO储锂性能的影响与机理分析";王梨梨;《中国优秀博硕士学位论文全文数据库(硕士)工程科技Ⅱ辑》;20190615;第23-24页 *

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