CN112885994A - Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof - Google Patents

Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof Download PDF

Info

Publication number
CN112885994A
CN112885994A CN202110309258.XA CN202110309258A CN112885994A CN 112885994 A CN112885994 A CN 112885994A CN 202110309258 A CN202110309258 A CN 202110309258A CN 112885994 A CN112885994 A CN 112885994A
Authority
CN
China
Prior art keywords
lithium
preparation
sulfur battery
sulfur
positive electrode
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.)
Pending
Application number
CN202110309258.XA
Other languages
Chinese (zh)
Inventor
尹海宏
赵晨媛
周宇祥
施天宇
王志亮
宋长青
秦琳
邵海宝
邓洪海
张振娟
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nantong University
Original Assignee
Nantong University
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nantong University filed Critical Nantong University
Priority to CN202110309258.XA priority Critical patent/CN112885994A/en
Publication of CN112885994A publication Critical patent/CN112885994A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/362—Composites
    • H01M4/366—Composites as layered products
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/052—Li-accumulators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/60—Heating or cooling; Temperature control
    • H01M10/62—Heating or cooling; Temperature control specially adapted for specific applications
    • H01M10/625—Vehicles
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/48—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides
    • H01M4/52—Selection of substances as active materials, active masses, active liquids of inorganic oxides or hydroxides of nickel, cobalt or iron
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/581—Chalcogenides or intercalation compounds thereof
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/58—Selection of substances as active materials, active masses, active liquids of inorganic compounds other than oxides or hydroxides, e.g. sulfides, selenides, tellurides, halogenides or LiCoFy; of polyanionic structures, e.g. phosphates, silicates or borates
    • H01M4/583—Carbonaceous material, e.g. graphite-intercalation compounds or CFx
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/028—Positive electrodes
    • 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
    • Y02E60/10—Energy storage using batteries

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Nanotechnology (AREA)
  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Battery Electrode And Active Subsutance (AREA)

Abstract

The invention belongs to the technical field of preparation of lithium-sulfur battery cathode materials, and discloses a lithium-sulfur battery cathode material with a core-shell structure, and a preparation method and application thereof, wherein the preparation method comprises the following steps: injecting sodium hydrogen selenide solution with pH of 11-11.2Adding carbon nano tube into zinc nitrate hexahydrate solution to prepare ZnSe-CNTs by a water phase method; then preparing ZnSe-CNTs/S core with sulfur powder by a melting method; finally, depositing nickel hydroxide as a shell on the inner core to prepare ZnSe-CNTs/S @ Ni (OH)2. The cathode material is applied to the lithium-sulfur battery, can improve the cycle stability and the rate capability of the lithium-sulfur battery, simultaneously inhibits the shuttle effect problem in the lithium-sulfur battery, and improves the electrochemical performance of the lithium-sulfur battery.

Description

Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof
Technical Field
The invention belongs to the technical field of preparation of lithium-sulfur battery cathode materials, and particularly relates to a lithium-sulfur battery cathode material with a core-shell structure, and a preparation method and application thereof.
Background
The Lithium Sulfur Battery (LSB) has a high energy density (2600Wh kg) compared to the lithium battery-1) High theoretical specific capacity (1675mAh g)-1) Low cost, excellent environmental friendliness, etc., but its application is hindered by some key problems. 1) Elemental sulfur and lithium sulfide generated by discharge are insulators, and the insulators are used as electrode materials and have low utilization rate of active substances and poor conductivity; (2) in the charging and discharging process, the conversion of elemental sulfur and lithium sulfide can change the volume of the positive electrode, so that the capacity of the battery is attenuated, and even the structure of the battery is damaged; (3) the shuttling effect of polysulfides, when lithium polysulfide dissolves in an organic electrolyte, creates a concentration difference between the positive and negative electrodes of the battery resulting in shuttling of lithium polysulfide between the positive and negative electrodes. Low lithium sulfide (Li) with electronic insulation due to shuttle effect2S/Li2S2) The lithium deposits on the surface of the negative electrode, reduces the ion conduction capability and loses a large amount of active substances (sulfur), thereby reducing the capacity and the service life of the battery. Thus, the shuttle effect, the severe volume expansion, the conductivity and the cycle of the lithium-sulfur battery in the prior artThe poor stability and safety performance become technical problems to be solved urgently by technical personnel in the field.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a lithium-sulfur battery positive electrode material with a core-shell structure, and a preparation method and application thereof.
In view of the above, the invention provides a lithium-sulfur battery positive electrode material with a core-shell structure, wherein the lithium-sulfur battery positive electrode material is ZnSe-CNTs/S @ Ni (OH)2The lithium-sulfur battery positive electrode material comprises a zinc selenide quantum dot modified carbon nano tube/sulfur inner core and a layered nickel hydroxide shell wrapped outside the inner core in a non-compact mode, and the particle size of the zinc selenide quantum dot is 3-6 nm. The nickel hydroxide is a layered nanostructure, allowing rapid electron/ion transfer.
The invention also provides a preparation method of the lithium-sulfur battery positive electrode material with the core-shell structure, which comprises the following steps:
1) under magnetic stirring, dissolving zinc nitrate hexahydrate in deionized water, adding 3-mercaptopropionic acid (MPA), adjusting the pH to 11.0-11.2, injecting a sodium hydroselenide solution under the protection of inert gas, then adding carbon nanotubes, carrying out heating reflux reaction, centrifuging, washing and drying to obtain zinc selenide quantum dot modified carbon nanotubes (ZnSe-CNTs);
2) mixing the zinc selenide quantum dot modified carbon nanotube and sulfur powder, grinding for 20-30 minutes, and then reacting under the protection of inert gas to obtain zinc selenide quantum dot modified carbon nanotube/sulfur core (ZnSe-CNTs/S);
3) ultrasonically dispersing the zinc selenide quantum dot modified carbon nano tube/sulfur core in deionized water, adding nickel sulfate hexahydrate under stirring to be completely dissolved, then sequentially adding ammonia water and ammonium persulfate, stirring for 30 minutes at room temperature, centrifuging, washing and drying to obtain ZnSe-CNT/S @ Ni (OH)2A composite material.
Preferably, in step 1), the preparation method of the sodium hydrogen selenide solution comprises the following steps: and under the ice bath condition, dissolving selenium powder and sodium borohydride in deionized water, and reacting for 6-8 h to obtain a sodium hydroselenide solution.
Preferably, the molar ratio of the sodium borohydride to the selenium powder is 2: 1.
Preferably, in the step 1), the molar ratio of the sodium hydrogen selenide in the sodium hydrogen selenide solution to the zinc nitrate hexahydrate is 1: 5.
Preferably, in the step 1), the using amount ratio of the zinc nitrate hexahydrate, the deionized water, the 3-mercaptopropionic acid and the carbon nano tubes is (1.19-2.97) g, 400ml and 700 mu L (0.15-0.3) g.
Preferably, in the step 1), the temperature of the heating reflux reaction is 80-100 ℃ and the time is 80-120 minutes.
Preferably, in the step 2), the mass ratio of the zinc selenide quantum dots modified carbon nano tubes to the sulfur powder is (6-7) to (4-3).
Preferably, in the step 3), the ultrasonic time is 10-15 minutes, and the dosage ratio of the nickel sulfate hexahydrate, the ammonia water and the ammonium persulfate is (1-2), (3-10) ml and (0.15-0.25) g.
The invention provides a lithium-sulfur battery, wherein the positive electrode of the lithium-sulfur battery is prepared from the positive electrode material of the lithium-sulfur battery or the preparation method of the lithium-sulfur battery.
Compared with the prior art, the method takes a ZnSe-CNTs network as a framework loaded with sulfur, and then Ni (OH) is carried out2And (4) coating to obtain the lithium-sulfur battery cathode material with the core-shell structure. Compared with the prior art, the anode material has the following technical effects:
(1) in the anode material, the carbon nano tube is used as a conductive framework for providing a rapid electron/ion transmission channel, the zinc selenide quantum dots modified on the carbon nano tube are polar materials, the particle size is small, the dispersibility is good, and more active sites can be provided by modifying the carbon nano tube.
(2) In the cathode material, on one hand, the porous network structure of the carbon nano tube can accommodate volume expansion caused by the transformation of sulfur into lithium sulfide, and on the other hand, a certain space is formed between the nickel hydroxide serving as a protective layer and the inner core coated by the nickel hydroxide to relieve the volume expansion, so that the structural integrity of the cathode material is ensured.
(3) Ni (OH) of the Positive electrode Material of the present invention2On one hand, the nanosheet shell can physically limit active substance sulfur from penetrating out of the shell to be dissolved in electrolyte, so that the problem of reduction of battery capacity caused by reduction of active substances is solved; on the other hand, Ni (OH) as a shell2The chemical adsorption effect is generated on polysulfide, the shuttle effect is reduced, and the problem of reduction of battery capacity caused by reduction of active substances deposited on the surface of a negative electrode after the polysulfide shuttles to the negative electrode is solved.
(4) The specific capacity of the cathode material used for the cathode of the lithium-sulfur battery at 0.2C is up to 1123mAh g-1And 621mAh g at 2C-1. Meanwhile, the composite material has good cycle performance, and the capacity retention rate is 80.7% after 150 cycles of 0.5C.
Drawings
Fig. 1 is a Transmission Electron Microscope (TEM) image of a zinc selenide quantum dot modified carbon nanotube obtained in the preparation process of embodiment 1 of the present invention;
FIG. 2 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2Scanning Electron Microscope (SEM) images of (a);
FIG. 3 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2High Resolution Transmission Electron Microscopy (HRTEM) images of;
FIG. 4 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2A schematic structural diagram;
FIG. 5 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2Transmission Electron Microscope (TEM) image of
FIG. 6 is a graph of the specific capacity and cycling performance of the lithium sulfur batteries of example 1 and comparative examples 1 and 2 provided by the present invention over a 150 cycle period at 0.5C;
fig. 7 is a graph of specific capacity and rate performance of the lithium-sulfur batteries of example 1 and comparative examples 1 and 2 provided by the present invention.
Detailed Description
In order to facilitate an understanding of the invention, the principles and features of the invention are described in full detail below with reference to the accompanying drawings and the preferred embodiments, which are provided for illustration only and are not limiting on the scope of the invention.
All of the starting materials of the present invention, without particular limitation as to their source, may be purchased commercially or prepared according to conventional methods well known to those skilled in the art.
In order to further illustrate the present invention, the following will describe in detail the preparation method and application of the lithium sulfur battery cathode material with core-shell structure provided by the present invention with reference to the examples.
Example 1
Firstly, 10mL of deionized water is added into a mixture of 0.31g of sodium borohydride and 0.32g of selenium powder, the reaction is cooled for 6 hours in an ice bath at 0 ℃, and colorless supernatant is sodium hydrogen selenide solution (NaHSe). The reaction vessel was covered with a rubber stopper with a needle during the reaction to release the pressure in the generated hydrogen.
And (II) dissolving 1.19g of zinc nitrate hexahydrate in 400ml of deionized water under magnetic stirring, adding 700 mu L of MPA, adding 10M of sodium hydroxide solution to adjust the pH of the mixed solution to 11.0, taking 1.2ml of the NaHSe solution obtained in the step (I) by using a syringe under the nitrogen atmosphere, injecting the solution into the solution, adding 0.15g of multi-walled carbon nano-tubes, and stirring for 30 minutes. The above mixture solution was then transferred to a three-necked flask and refluxed at 80 ℃ for 80 minutes to obtain ZnSe-CNTs.
And thirdly, centrifuging, washing and drying the 0.2g of zinc selenide quantum dot modified carbon nano tube material obtained in the step two, mixing with 0.3g of sulfur powder, grinding for 20 minutes, then putting the ground powder into a reaction kettle in a glove box under the argon atmosphere, and finally placing the reaction kettle in a blowing drying box at 160 ℃ for reaction for 14 hours to obtain the ZnSe-CNTs/S composite material.
(IV) ultrasonically dispersing 0.45g of ZnSe-CNTs/S kernel in the step (III) in 30ml of deionized water for 10 minutes, then adding 1.05g of nickel sulfate hexahydrate and stirring for 3 minutes, adding 3ml of ammonia water and 0.15g of ammonium persulfate, stirring for 30 minutes at room temperature, centrifuging and washing to obtain ZnSe-CNT/S @ Ni (OH)2And (3) a positive electrode material. And finally, drying the materials in a vacuum oven at the temperature of 60-75 ℃ for 12 hours.
Fig. 1 is a Transmission Electron Microscope (TEM) image of the carbon nanotube modified by the zinc selenide quantum dots obtained in the preparation process of the embodiment, and it can be seen from fig. 1 that a plurality of ZnSe quantum dots are modified on the outer surface of the carbon nanotube, and the size of the ZnSe quantum dots is about 3-6 nm. FIG. 2 shows ZnSe-CNTs/S @ Ni (OH)2SEM image of (A). As can be seen from FIG. 2, the nano-flaky nickel hydroxide is non-tightly coated outside the ZnSe-CNTs/S tubular core structure to form a core-shell structure. FIG. 3 shows ZnSe-CNTs/S @ Ni (OH)2The lattice spacing of the three substances is clearly visible in a high-resolution transmission electron microscope (HRTEM). FIG. 4 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2The structural schematic diagram shows that the material has a core-shell structure, and a ZnSe-CNTs/S core is wrapped in Ni (OH)2Inside the shell, zinc selenide quantum dots are well modified on the surface of the carbon nano tube. FIG. 5 shows ZnSe-CNTs/S @ Ni (OH) obtained in example 1 of the present invention2In a Transmission Electron Microscope (TEM) image of (A), Ni (OH) can be observed2The layered nano-sheets are not tightly wrapped on the surface of the ZnSe-CNTs/S inner core.
(V) preparation of slurry: 0.45g of ZnSe-CNTs/S @ Ni (OH)20.13g of conductive carbon black and 0.065g of binder LA133 are mixed, ground and mixed in an agate mortar to prepare slurry, the slurry is uniformly coated on an aluminum foil by adopting a blade coating method, and the aluminum foil is dried for 12 hours at 60 ℃ to obtain the positive plate.
(VI) manufacturing an electrode plate: the positive sheet was cut into circular pole pieces with a diameter of 16 mm.
(VII) manufacturing of the lithium-sulfur battery: the round pole piece is used as the anode, Celgard 2500 is used as the diaphragm, the commercial lithium metal piece is used as the cathode, and 0.1M LiNO is added3+1M electrolyte of DOL/DME (volume ratio 1:1) of LiTFSI and oxygen content in water lower than 0.1ppmAnd (3) completing the assembly of the 2032 type button cell in a glove box filled with argon, standing for 12h, and then testing the electrochemical performance.
Example 2
Firstly, 10mL of deionized water is added into a mixture of 0.465g of sodium borohydride and 0.48g of selenium powder, the reaction is cooled for 8 hours in an ice bath at 0 ℃, and the supernatant is a sodium hydrogen selenide solution (NaHSe). The reaction vessel was covered with a rubber stopper with a needle during the reaction to release the pressure in the generated hydrogen.
And (II) dissolving 2.97g of zinc nitrate hexahydrate in 400ml of deionized water under magnetic stirring, adding 700 mu L of MPA, adding 8M sodium hydroxide solution to adjust the pH of the solution to 11.2, injecting 2.4ml of the NaHSe solution obtained in the step (I) into the solution by using a syringe under the nitrogen atmosphere, adding 0.2g of multi-walled carbon nano-tube, and stirring for 30 minutes. The above mixture solution was then transferred to a three-necked flask and refluxed at 100 ℃ for 120 minutes to obtain a ZnSe-CNTs material.
And thirdly, centrifuging, washing and drying the 0.2g of zinc selenide quantum dot modified carbon nano tube material obtained in the step two, mixing with 0.3g of sulfur powder, grinding for 20 minutes, then putting the ground powder into a reaction kettle in a glove box under the argon atmosphere, and finally placing the reaction kettle in a forced air drying box at 155 ℃ for reaction for 12 hours to obtain the ZnSe-CNTs/S composite material.
(IV) ultrasonically dispersing 0.45g of ZnSe-CNTs/S kernel in the step (III) in 30ml of deionized water for 15 minutes, then adding 2g of nickel sulfate hexahydrate and stirring for 3 minutes, adding 10ml of ammonia water and 0.25g of ammonium persulfate, stirring for 30 minutes at room temperature, centrifuging and washing to obtain ZnSe-CNT/S @ Ni (OH)2And (3) a positive electrode material. And finally, drying the materials in a vacuum oven at the temperature of 60-75 ℃ for 12 hours.
Comparative example 1
Preparation of carbon nanotube/sulfur composite (CNTs/S): grinding 0.2g of multi-walled Carbon Nanotubes (CNT) and 0.3g of sublimed sulfur in an agate mortar for 30min, then putting the ground powder into a reaction kettle in a glove box under the atmosphere of inert gas, and finally putting the reaction kettle into a blowing drying box at 160 ℃ for reaction for 14 h.
(II) preparation of slurry: mixing 0.45g of CNTs/S, 0.13g of conductive carbon black and 0.065g of LA133 as a binder, grinding and mixing in an agate mortar to prepare slurry, uniformly coating the slurry on an aluminum foil by adopting a blade coating method, and drying at 60 ℃ for 12 hours to obtain the positive plate.
(III) manufacturing an electrode plate: the dried positive electrode sheet was cut into circular pole pieces with a diameter of 16 mm.
(IV) preparation of lithium-sulfur battery: the round pole piece is used as the anode, Celgard 2500 is used as the diaphragm, the commercial lithium metal piece is used as the cathode, and 0.1M LiNO is added3And assembling a 2032 type button cell in an argon-filled glove box with the water oxygen content lower than 0.1ppm by using electrolyte of DOL/DME (volume ratio of 1:1) of +1M LiTFSI, and standing for 12h to test the electrochemical performance.
Comparative example 2
Firstly, 10mL of deionized water is added into a mixture of 0.465g of sodium borohydride and 0.48g of selenium powder, the reaction is cooled for 8 hours in an ice bath at 0 ℃, and the supernatant is a sodium hydrogen selenide solution (NaHSe). The reaction vessel was covered with a rubber stopper with a needle during the reaction to release the pressure in the generated hydrogen.
And (II) dissolving 2.97g of zinc nitrate hexahydrate in 400ml of deionized water under magnetic stirring, adding 700 mu L of MPA, adding 8M sodium hydroxide solution to adjust the pH of the solution to 11.2, injecting 2.4ml of the NaHSe solution obtained in the step (I) into the solution by using a syringe under the nitrogen atmosphere, adding 0.2g of multi-walled carbon nano-tube, and stirring for 30 minutes. And transferring the mixture solution into a three-neck flask, and refluxing at 100 ℃ for 120 minutes to obtain a zinc selenide quantum dot modified carbon nanotube material (ZnSe-CNTs).
And thirdly, centrifuging, washing and drying the material of the zinc selenide quantum dot modified CNT (0.2 g) obtained in the step (II), mixing the material with sulfur powder of 0.3g, grinding for 20-30 minutes, then putting the ground powder into a reaction kettle in a glove box under the argon atmosphere, and finally placing the reaction kettle in a blast drying box at 160 ℃ for reaction for 14 hours to obtain the zinc selenide quantum dot modified carbon nanotube/sulfur composite material (ZnSe-CNTs/S).
(IV) preparation of slurry: mixing 0.45g of ZnSe-CNTs/S, 0.13g of conductive carbon black and 0.065g of LA133 as a binder, grinding and mixing in an agate mortar to prepare slurry, uniformly coating the slurry on an aluminum foil by adopting a blade coating method, and drying at 60 ℃ for 12 hours to obtain the positive plate.
(V) manufacturing an electrode plate: the dried positive electrode sheet was cut into circular pole pieces with a diameter of 16 mm.
(VI) preparation of lithium-sulfur battery: the round pole piece is used as the anode, Celgard 2500 is used as the diaphragm, the commercial lithium metal piece is used as the cathode, and 0.1M LiNO is added3And assembling a 2032 type button cell in an argon-filled glove box with the water oxygen content lower than 0.1ppm by using electrolyte of DOL/DME (volume ratio of 1:1) of +1M LiTFSI, and standing for 12h to test the electrochemical performance.
Test example
The lithium sulfur batteries obtained in example 1 and comparative examples 1 and 2 were subjected to constant current charging and discharging, cycle performance testing and rate performance testing by using a charging and discharging instrument of xinwei limited company, shenzhen, wherein the testing temperature is 26 ℃ at ambient temperature, the cut-off range of the charging and discharging voltage is 1.7-2.8V, and the testing results are shown in fig. 6 and 7.
Fig. 6 is a graph of specific capacity and cycle performance of the lithium-sulfur battery of example 1 and comparative examples 1 and 2 provided by the present invention over 150 cycle periods at 0.5C. ZnSe-CNTs/S @ Ni (OH) provided in example 12The specific discharge capacity of the lithium-sulfur battery assembled as the positive electrode material is 942mAh g from the first circle-1The specific discharge capacity of the alloy is 760mAh g after 150 circles-1The capacity retention rate is 80.7%, the coulombic efficiency is about 99%, the cycling stability is very good, as can be seen from figure 6, the specific capacity of the comparative examples 1 and 2 is obviously lower than that of ZnSe-CNTs/S @ Ni (OH)2A lithium sulfur battery as a positive electrode. Fig. 7 is a graph of specific capacity and rate performance of the lithium-sulfur batteries of example 1 and comparative examples 1 and 2 provided by the present invention. As can be seen from FIG. 7, ZnSe-CNTs/S @ Ni (OH) provided in example 12The rate performance of the lithium-sulfur battery assembled as the cathode material is between 0.2C and 2C, and the specific discharge capacities of the lithium-sulfur battery at 0.2C, 0.5C, 1C and 2C are 1123, 901, 722 and 622mAh g respectively-1. When the current density rose back to 2C, the corresponding capacity recovered to 953mAhg-1. The lithium-sulfur batteries using the materials of comparative examples 1 and 2 as electrodes have the advantages of rapid capacity attenuation, poor discharge specific capacity and stability, serious shuttle effect and extremely low utilization rate of active substances. ZnSe-CNTs/S @ Ni (OH)2The lithium-sulfur battery taking the material as the electrode has excellent rate performance, high stability, excellent electrochemical performance, and better initial specific capacity, cycle performance and rate performance.
The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.

Claims (10)

1. The lithium-sulfur battery positive electrode material with the core-shell structure is characterized in that the positive electrode material is ZnSe-CNT/S @ Ni (OH)2The anode material comprises a zinc selenide quantum dot modified carbon nano tube/sulfur inner core and a nickel hydroxide shell wrapped outside the inner core in a non-compact manner, wherein the particle size of the zinc selenide quantum dot is 3-6 nm; the nickel hydroxide is in a layered nano structure.
2. A preparation method of a lithium-sulfur battery positive electrode material with a core-shell structure is characterized by comprising the following steps:
1) under magnetic stirring, dissolving zinc nitrate hexahydrate in deionized water, adding 3-mercaptopropionic acid, adjusting the pH to 11.0-11.2, injecting a sodium hydroselenide solution under the protection of inert gas, then adding a carbon nano tube, carrying out heating reflux reaction, centrifuging, washing and drying to obtain a zinc selenide quantum dot modified carbon nano tube;
2) mixing the zinc selenide quantum dot modified carbon nanotube and sulfur powder, grinding for 20-30 minutes, and reacting under the protection of inert gas to obtain a zinc selenide quantum dot modified carbon nanotube/sulfur core;
3) ultrasonically dispersing the zinc selenide quantum dot modified carbon nano tube/sulfur kernel in deionized water, and adding sulfuric acid hexahydrate under the stirring conditionStirring nickel until nickel is completely dissolved, then sequentially adding ammonia water and ammonium persulfate, stirring for 30 minutes at room temperature, centrifuging, washing and drying to obtain ZnSe-CNT/S @ Ni (OH)2A composite material.
3. The method for preparing a sodium hydroselenide solution according to claim 2, wherein the method for preparing a sodium hydroselenide solution in step 1) comprises: and under the ice bath condition, dissolving selenium powder and sodium borohydride in deionized water, and reacting for 6-8 h to obtain a sodium hydroselenide solution.
4. The preparation method according to claim 3, wherein the molar ratio of the sodium borohydride to the selenium powder is 2: 1.
5. The production method according to claim 2, wherein in step 1), the molar ratio of sodium hydroselenide in the sodium hydroselenide solution to the zinc nitrate hexahydrate is 1: 5.
6. The preparation method of claim 2, wherein in the step 1), the ratio of the zinc nitrate hexahydrate, the deionized water, the 3-mercaptopropionic acid and the carbon nanotubes is (1.19-2.97) g to 400ml to 700 μ L (0.15-0.3) g.
7. The preparation method according to claim 2, wherein in the step 1), the temperature of the heating reflux reaction is 80 to 100 ℃ and the time is 80 to 120 minutes.
8. The preparation method of claim 2, wherein in the step 2), the mass ratio of the zinc selenide quantum dots modified carbon nanotubes to the sulfur powder is (6-7) to (4-3).
9. The preparation method according to claim 2, wherein in the step 3), the ultrasonic treatment time is 10-15 minutes, and the using amount ratio of the nickel sulfate hexahydrate, the ammonia water and the ammonium persulfate is (1-2) g, (3-10) ml and (0.15-0.25) g.
10. A lithium-sulfur battery, wherein the positive electrode is the lithium-sulfur battery positive electrode material according to claim 1 or the lithium-sulfur battery positive electrode material prepared by the preparation method according to any one of claims 2 to 9.
CN202110309258.XA 2021-03-23 2021-03-23 Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof Pending CN112885994A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110309258.XA CN112885994A (en) 2021-03-23 2021-03-23 Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110309258.XA CN112885994A (en) 2021-03-23 2021-03-23 Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof

Publications (1)

Publication Number Publication Date
CN112885994A true CN112885994A (en) 2021-06-01

Family

ID=76041926

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110309258.XA Pending CN112885994A (en) 2021-03-23 2021-03-23 Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof

Country Status (1)

Country Link
CN (1) CN112885994A (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101220275A (en) * 2008-01-24 2008-07-16 上海交通大学 Hydrothermal production method for water-soluble ZnCdSe quantum dot
CN105118972A (en) * 2015-07-06 2015-12-02 浙江大学 Metal hydroxide coated carbon and sulfur lithium-sulfur battery positive electrode material, and preparation method and application thereof
CN109273703A (en) * 2018-12-10 2019-01-25 山东大学 A kind of lithium-sulphur cell positive electrode graphene/sulphur/nickel hydroxide self-supporting composite material and preparation method
US20190326587A1 (en) * 2018-04-18 2019-10-24 Nanotek Instruments, Inc. Selenium Loaded Mesoporous Carbon Cathode for Alkali Metal-Selenium Secondary Battery

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101220275A (en) * 2008-01-24 2008-07-16 上海交通大学 Hydrothermal production method for water-soluble ZnCdSe quantum dot
CN105118972A (en) * 2015-07-06 2015-12-02 浙江大学 Metal hydroxide coated carbon and sulfur lithium-sulfur battery positive electrode material, and preparation method and application thereof
US20190326587A1 (en) * 2018-04-18 2019-10-24 Nanotek Instruments, Inc. Selenium Loaded Mesoporous Carbon Cathode for Alkali Metal-Selenium Secondary Battery
CN109273703A (en) * 2018-12-10 2019-01-25 山东大学 A kind of lithium-sulphur cell positive electrode graphene/sulphur/nickel hydroxide self-supporting composite material and preparation method

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
DAWEI YANG等: ""ZnSe/N-Doped Carbon Nanoreactor with Multiple Adsorption Sites for Stable Lithium–Sulfur Batteries"", 《ACS NANO》, vol. 14, no. 11, pages 15492 - 15504 *
JIAN JIANG等: ""Encapsulation of sulfur with thin-layered nickel-based hydroxides for long-cyclic lithium–sulfur cells"", 《NATURE COMMUNICATIONS》, vol. 6, pages 1 - 9 *

Similar Documents

Publication Publication Date Title
CN107425185B (en) Preparation method of carbon nanotube-loaded molybdenum carbide material and application of carbon nanotube-loaded molybdenum carbide material in lithium-sulfur battery positive electrode material
CN111180714B (en) Carbon/molybdenum dioxide/silicon/carbon composite material, battery cathode comprising same and lithium ion battery
CN111313000B (en) Lithium-sulfur battery positive electrode material and preparation method and application thereof
CN102208608A (en) Preparation method of carbon-sulfur composite material for lithium ion battery carbon cathode material
CN111613789B (en) Nano carbon/metal sulfide composite porous material and preparation method and application thereof
CN110790322B (en) Core-shell nickel ferrite and preparation method thereof, nickel ferrite @ C material and preparation method and application thereof
CN103000864A (en) Sulfur composite cathode material and preparation method thereof
CN114447305B (en) Multi-carbon-based quick-charge anode composite material and preparation method thereof
CN111668453A (en) Flexible self-supporting positive electrode material and preparation method and application thereof
CN105428618A (en) Preparation method for shell-core type carbon-coated metal sulfide nano-composite particles and application of particles
CN112038591A (en) Magnesium-sulfur battery, transition metal sulfide/sulfur composite positive electrode material and composite method
CN107863504A (en) A kind of preparation method of core shell structure Si-C composite material
CN110224126B (en) Iron-nickel sulfide nano material and preparation method and application thereof
CN114520320B (en) Lithium oxide composite positive electrode material based on alkali metal reduction method
CN109950503B (en) CoMoOxPreparation method of/carbon/sulfur composite nano material, lithium ion battery cathode and lithium ion half battery
CN110752359B (en) Preparation method of sulfur-three-dimensional hollow graphene-carbon nanotube composite lithium-sulfur battery positive electrode material
CN110649237A (en) Iron oxide @ carbon nanocomposite and preparation method and application thereof
CN113130879B (en) Preparation method of high-adsorption catalytic performance cathode material of lithium-sulfur battery
CN111446454B (en) Application of electronic compound as lithium air battery anode catalyst material
CN112885994A (en) Lithium-sulfur battery positive electrode material with core-shell structure and preparation method and application thereof
CN115513468B (en) Preparation method of CNTs/OMC ordered microporous carbon nanospheres and application method of CNTs/OMC ordered microporous carbon nanospheres in lithium-sulfur battery
CN115241421A (en) Lithium-sulfur battery positive electrode material with xanthium-shaped structure and preparation method and application thereof
CN117393742B (en) Negative graphene-based material of lithium ion battery and preparation method thereof
CN113793914B (en) Reduced graphene oxide coated CNTs/SnO with hollow structure 2 Composite film and preparation method and application thereof
CN115566257A (en) One-dimensional carbon material modified sulfide solid electrolyte and preparation method and application thereof

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