CN110311111B - N-doped CNT in-situ coated Co nanoparticle composite material and preparation and application thereof - Google Patents

N-doped CNT in-situ coated Co nanoparticle composite material and preparation and application thereof Download PDF

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CN110311111B
CN110311111B CN201910583435.6A CN201910583435A CN110311111B CN 110311111 B CN110311111 B CN 110311111B CN 201910583435 A CN201910583435 A CN 201910583435A CN 110311111 B CN110311111 B CN 110311111B
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CN110311111A (en
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刘军
王卓森
梁明森
赵尉铭
朱敏
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South China University of Technology SCUT
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    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
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    • H—ELECTRICITY
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    • 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
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Abstract

The invention belongs to the field of nano composite materials, and discloses an N-doped CNT in-situ coated Co nano particle composite material and preparation and application thereof. Dissolving urea, boric acid, polyethylene glycol and cobalt nitrate in water, stirring and mixing uniformly, heating to completely volatilize the solvent, drying to obtain precursor powder, and then carrying out heat treatment to obtain the N-doped CNT in-situ coated Co nanoparticle composite material. According to the invention, N-doped CNT is obtained through in-situ thermal polymerization, and Co nanoparticles are loaded in the carbon nanotube through in-situ reduction action, so that the N-doped CNT in-situ coated Co nanoparticle composite material with controllable appearance, uniform size and good structural stability is prepared, and after S loading is carried out on the obtained composite material, excellent electrochemical performance including good cycle stability and higher reversible specific capacity is shown as a lithium-sulfur battery anode material due to excellent conductivity and electrochemical catalysis.

Description

N-doped CNT in-situ coated Co nanoparticle composite material and preparation and application thereof
Technical Field
The invention belongs to the field of nano composite materials, and particularly relates to an N-doped CNT in-situ coated Co nano particle composite material, and preparation and application thereof.
Background
With the development of society, lithium ion secondary batteries have become the first choice for power sources of various electronic products due to the advantages of higher working voltage, longer cycle life, cycle stability and the like. However, with the rapid development of portable electronic devices and new energy vehicles, the demand for chemical power sources having high energy density is rapidly increasing. The types of the anode and cathode materials of the commercial lithium ion battery are more, and if the anode and cathode active substances are lithium ion 'de-intercalation' materials, the mass ratio energy of the anode and cathode active substances is difficult to exceed 300 W.h/kg, so that a novel battery material with higher mass ratio energy is urgently needed to be developed to meet the requirements of future social and economic development. Currently, the development of new electrochemical energy storage systems is a major concern and a common technical challenge for researchers in all countries of the world. Therefore, the search for a new novel energy storage system with higher mass ratio energy is always a research hotspot in the field of energy storage.
The concept of lithium-sulphur batteries was first presented in the 60's of the 19 th century. Today, society has an ever increasing need for high-energy batteries. Lithium-sulfur batteries are also attracting attention because of their high mass energy density of 2600W · h/kg, and are also expected to find application as next-generation high energy density battery systems. In addition, the sulfur as the positive active material in the lithium-sulfur battery has the advantages of rich reserves, low cost, environmental friendliness and the like. The working principle of the lithium-sulfur battery is that energy is stored and released through reversible electrochemical reaction between metal lithium and elemental sulfur, and the theoretical energy density of the lithium-sulfur battery is 3-5 times that of the existing lithium-ion battery.
Although the lithium-sulfur battery has higher theoretical specific capacity and energy density, the lithium-sulfur battery still has many problems in some aspects as a novel battery, such as too fast capacity fading, low coulombic efficiency and the like, and the series of problems limit the further promotion of the lithium-sulfur battery to commercialization. The main reasons for this series of problems include: firstly, elemental sulfur itself and final product Li of reaction2S and Li2S2Poor electronic and ionic conductivity; ② due to sulfur simple substance and generated Li2S and Li2The density of S is greatly different, so that volume expansion (80%) to a certain degree can be caused, and larger internal stress is caused, so that the falling of active substances is caused, and the overall performance of the battery is influenced; and thirdly, in the charging and discharging process, the generated polysulfide intermediate product can generate shuttle effect, so that the problems of too fast capacity attenuation, short cycle life and the like are solved, and the utilization rate of the electrode active substance and the cycle life of the battery are reduced. Seriously hampering the commercialization process of lithium-sulfur batteries.
The inherent characteristic defect of the elemental sulfur is a terrorist who is the main problem of the lithium-sulfur battery, so the modification research on the anode material is used for solving the problem of the lithium-sulfur battery and is a main way for improving the battery performance.
In recent years, sulfur-carbon composite materials, and nano metal particle-sulfur composite materials and the like have received much attention from researchers. However, the single sulfur-carbon composite and the nanometal compound-sulfur composite have disadvantages of poor polysulfide-limiting performance and poor electrical conductivity. Therefore, if the advantages of the two materials can be combined to obtain the hybrid material of the nano metal particles and the carbon, the performance of the lithium-sulfur battery can be expected to be further improved.
Disclosure of Invention
Aiming at the defects and shortcomings of the prior art, the invention mainly aims to provide a preparation method of an N-doped CNT in-situ coated Co nanoparticle composite material. The method comprises the steps of adjusting the content of the coated Co nanoparticles, obtaining a precursor through high-molecular polymerization and in-situ reduction, and then carrying out heat treatment to obtain the N-doped CNT in-situ coated Co nanoparticle composite material.
Another object of the present invention is to provide an N-doped CNT in-situ coated Co nanoparticle composite prepared by the above method.
The invention further aims to provide an application of the N-doped CNT in-situ coated Co nanoparticle composite material as a lithium-sulfur battery positive electrode material.
The purpose of the invention is realized by the following technical scheme:
a preparation method of an N-doped CNT in-situ coated Co nanoparticle composite material comprises the following preparation steps:
(1) dissolving urea, boric acid, polyethylene glycol (PEG) and cobalt nitrate in water, stirring and mixing uniformly, heating to completely volatilize the solvent, and drying to obtain precursor powder;
(2) and (2) carrying out heat treatment on the precursor powder obtained in the step (1) to obtain the N-doped CNT in-situ coated Co nanoparticle composite material.
Preferably, the mass ratio of the polyethylene glycol to the cobalt nitrate in the step (1) is 0.5 (0.2-0.6); more preferably 0.5: 0.4.
Preferably, the drying temperature in the step (1) is 60-80 ℃.
Preferably, the heat treatment in the step (2) is carried out in an argon atmosphere, the heat treatment temperature is 700-900 ℃, and the time is 4-6 hours.
An N-doped CNT in-situ coated Co nanoparticle composite material is prepared by the method.
Furthermore, the diameter of the N-doped CNT in-situ coated Co nanoparticle composite material is 1-1.5 mu m.
The application of the N-doped CNT in-situ coated Co nanoparticle composite material as a lithium-sulfur battery anode material comprises the following application processes: and uniformly mixing the N-doped CNT in-situ coated Co nanoparticle composite material with elemental sulfur, heating and preserving heat for reaction, further carrying out heat treatment on the reaction product, and removing redundant S to obtain the lithium-sulfur battery anode material.
Preferably, the mass ratio of the N-doped CNT in-situ coated Co nanoparticle composite material to elemental sulfur is 1 (3-4).
Preferably, the temperature of the heating and heat preservation reaction is 155-200 ℃, and the time is 12-16 h.
Preferably, the heat treatment is heating to 200-250 ℃ at a heating rate of 1-3 ℃/min for 0.5-2 h under an argon atmosphere.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the preparation method of the invention generates the N-doped carbon nano tube in situ through high-temperature polymerization.
(2) According to the preparation method, Co nanoparticles are loaded in the carbon nano tubes through in-situ thermal reduction to obtain the Co @ CNT.
(3) After the N-doped Co @ CNT composite material is subjected to S loading, the excellent double-layer absorption and catalysis effects enable the N-doped Co @ CNT composite material to be used as a lithium-sulfur battery anode material to show excellent electrochemical properties, including excellent cycling stability and higher reversible specific capacity.
Drawings
FIG. 1 is an SEM image of the Co @ CNT (4h) powder obtained in example 1;
FIG. 2 is an SEM image of the Co @ CNT (5h) powder obtained in example 2;
FIG. 3 is an SEM image of the Co @ CNT (6h) powder obtained in example 3;
FIG. 4 is an SEM image of the Co @ CNT (5h-1) powder obtained in example 4;
FIG. 5 is an SEM image of the Co @ CNT (5h-2) powder obtained in example 5;
FIG. 6 is an SEM image of the Co @ CNT (5h-3) powder obtained in example 6;
FIG. 7 is an XRD pattern of Co @ CNT (5h-2) prepared in example 5 compared to a standard control;
FIG. 8 is a TG plot of the Co @ CNT (5h-2) cathode material prepared in example 7;
FIG. 9 is a graph of the cycling performance at 0.1C for the Co @ CNT (5h-2) prepared in example 7, the Co @ CNT (5h-1) prepared in example 8, and the Co @ CNT (5h-3) cathode material prepared in example 9;
FIG. 10 is a charge-discharge diagram of the Co @ CNT (5h-2) cathode material prepared in example 7 at 0.1C.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited thereto.
Example 1
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.4 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(4) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the collected precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the argon atmosphere, and preserving the heat for 4 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (4 h).
SEM image of the resulting Co @ CNT (4h) powder referring to fig. 1, it can be seen that the material is filled with a large number of platelets and some of them have become tubes with a diameter of 200 nm.
Example 2
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.4 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(4) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the collected precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the argon atmosphere, and preserving the heat for 5 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (5 hours).
The SEM image of the obtained Co @ CNT (5h) powder is shown in FIG. 2, and it can be seen that no sheet is formed in the product, and all the precursors are changed into carbon nanotubes with the length of about 1-1.5 μm.
Example 3
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.4 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(4) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the collected precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the argon atmosphere, and preserving the heat for 6 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (6 h).
SEM image of the resulting Co @ CNT (6h) powder referring to fig. 3, the precursor has been converted into carbon nanotubes, but its surface is covered with a large number of nanoparticles.
Example 4
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.2 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(5) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the atmosphere of argon, and preserving heat for 5 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (5 h-1).
SEM image of the obtained Co @ CNT (5h-1) powder is shown in FIG. 4, and the precursor is changed into carbon nano-tubes with uniform appearance.
Example 5
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.4 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(5) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the collected precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the atmosphere of argon, and preserving the heat for 5 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (5 h-2).
The SEM image of the obtained Co @ CNT (5h-2) powder is shown in FIG. 5, and the obtained carbon nanotube has a smooth surface, uniform appearance and no flaky objects, so that the carbon nanotube with the best appearance can be obtained under the conditions and the mixture ratio.
The XRD pattern of the Co @ CNT (5h-2) powder obtained in the example and the standard control is shown in FIG. 7, and the peak value of the Co @ CNT (5h-2) obtained by preparation is consistent with that of standard card JCPDF # 01-089-.
Example 6
(1) 5 grams of urea was dissolved in 150mL of deionized water and stirred at room temperature for 10 minutes;
(2) adding 0.5 mg of PEG into the solution in the step (1), and keeping magnetic stirring at room temperature;
(3) 0.6 mg of Co (NO)3)2·6H2Adding O into the solution in the step (2), and keeping magnetic stirring at room temperature;
(5) adding 0.3 mg of boric acid into the solution (3), and continuing stirring for 30 minutes;
(5) finally, heating the mixed solution in the step (4) in an oil bath kettle for 12 hours to completely volatilize the solvent;
(6) collecting the pink precipitate obtained in the step (5), putting the collected precursor powder into an oven, and drying for 8h at 80 ℃;
(7) putting the pink powder in the step (6) into a porcelain boat, heating to 900 ℃ in a tube furnace under the atmosphere of argon, and preserving heat for 5 hours to obtain the N-doped CNT in-situ coated Co nanoparticle composite material Co @ CNT (5 h-3).
Referring to fig. 6, the SEM image of the obtained Co @ CNT (5h-3) powder shows that the precursor has been turned into carbon nanotubes, but a large amount of cobalt nitrate is added, and many particulate matters are precipitated outside the carbon nanotubes.
Example 7
The preparation method of the Co @ CNT (5h-2) positive electrode material specifically comprises the following steps:
(1) uniformly mixing the Co @ CNT (5h-2) obtained in the example 5 and a sulfur simple substance according to the mass ratio of 1:4, and then putting the mixture into a reaction kettle for heat preservation at 155 ℃ for 12 hours to obtain Co @ CNT (5h-2) -S;
(2) and (2) respectively putting the Co @ CNT (5h-2) -S obtained in the step (1) into a tube furnace, heating to 200 ℃ per minute at a heating rate of 1 ℃ in an argon atmosphere, and keeping the temperature for 0.5 hour to remove S simple substances adsorbed on the surface, thereby obtaining the Co @ CNT (5h-2) -S positive electrode material.
Thermogravimetric analysis was performed on the prepared Co @ CNT (5h-2) -S positive electrode material, and the analysis result is shown in fig. 8, and it can be seen from fig. 8 that the mass ratio of S in the material is 76%.
The prepared Co @ CNT (5h-2) -S positive electrode material, a conductive agent (Super-P) and a binder (sodium alginate) are uniformly mixed according to the mass ratio of 7:2:1, and then the mixture is coated on an aluminum foil to be manufactured into an electrode slice, and the electrode slice is dried in a vacuum drying oven for 12 hours.
The electrode plate is used in an argon atmosphere glove box, and a button cell is assembled by using metal lithium as a counter electrode for testing. The test conditions were: the charge-discharge current density is 0.1C (1C is 1675mA/g), and the charge-discharge cut-off voltage is 1.7-2.8V. The tested cycle number-specific capacity performance curveAs shown in FIG. 9, it can be seen from FIG. 9 that the first reversible capacity of the battery was 1440mA h g-1Capacity fade of 1080mA hr g after 100 weeks of cycling-1The attenuation rate was 0.25%.
Example 8
The preparation method of the Co @ CNT (5h-1) -S positive electrode material specifically comprises the following steps:
(1) uniformly mixing the Co @ CNT (5h-1) obtained in the example 4 and sulfur elementary substance according to the mass ratio of 1:4, and then putting the mixture into a reaction kettle to react for 12 hours at 155 ℃ to obtain Co @ CNT (5h-1) -S;
(2) and (2) respectively putting the Co @ CNT (5h-1) -S obtained in the step (1) into a tube furnace, heating to 200 ℃ per minute at a heating rate of 1 ℃ in an argon atmosphere, and keeping the temperature for 0.5 hour to remove S simple substances adsorbed on the surface, thereby obtaining the Co @ CNT (5h-1) -S positive electrode material.
The obtained Co @ CNT (5h-1) -S positive electrode material, a conductive agent (Super-P) and a binder (sodium alginate) are uniformly mixed according to the mass ratio of 7:2:1, and then the mixture is coated on an aluminum foil to be made into an electrode slice, and the electrode slice is dried in a vacuum drying oven for 12 hours.
The electrode plate is used in an argon atmosphere glove box, and a button cell is assembled by using metal lithium as a counter electrode for testing. The test conditions were: the charge-discharge current density is 0.1C (1C: 1675mA/g), and the charge-discharge cut-off voltage is 1.7-2.8V. The cycle performance chart obtained by the test is shown in FIG. 9, and as can be seen from FIG. 9, the first reversible capacity of the battery is 1360mA h g-1The discharge capacity after 100 cycles was maintained at 780mA hr g-1The reversibility and cycling stability of the cell were inferior to that of Co @ CNT (5h-2) -S.
Example 9
The preparation method of the Co @ CNT (5h-3) -S cathode material comprises the following steps:
(1) uniformly mixing the Co @ CNT (5h-3) obtained in the example 6 and sulfur elementary substance according to the mass ratio of 1:4, and then putting the mixture into a reaction kettle to react for 12 hours at 155 ℃ to obtain Co @ CNT (5h-3) -S;
(2) and (2) respectively putting the Co @ CNT (5h-3) -S obtained in the step (1) into a tube furnace, heating to 200 ℃ per minute at a heating rate of 1 ℃ in an argon atmosphere, and keeping the temperature for 0.5 hour to remove S simple substances adsorbed on the surface, thereby obtaining the Co @ CNT (5h-3) -S positive electrode material.
The obtained Co @ CNT (5h-3) -S positive electrode material, a conductive agent (Super-P) and a binder (sodium alginate) are uniformly mixed according to the mass ratio of 7:2:1, and then the mixture is coated on an aluminum foil to be made into an electrode slice, and the electrode slice is dried in a vacuum drying oven for 12 hours.
The electrode plate is used in an argon atmosphere glove box, and a button cell is assembled by using metal lithium as a counter electrode for testing. The test conditions were: the charge-discharge current density is 0.1C (1C is 1675mA/g), and the charge-discharge cut-off voltage is 1.7-2.8V. The cycle performance graph obtained by the test is shown in FIG. 9, and as can be seen from FIG. 9, the first reversible capacity of the battery is 1200mA h g-1The discharge capacity after 100 cycles was kept at 490mA h g-1The reversibility and cycling stability of the cell were inferior to those of Co @ CNT (5h-2) -S and Co @ CNT (5h-1) -S.
From the above, when the heating temperature is 900 ℃, the holding time is 5h, and the relative amount of cobalt nitrate is 2, the obtained material Co @ CNT (5h-2) has the best electrochemical performance. The charge-discharge curve of the material is shown in fig. 10, and it can be seen from the graph that two obvious discharge platforms are shown at 2.3v and 2.1v in the discharge process. A distinct charging plateau was exhibited at 2.35v during the charging process. These platforms are typical lithium-sulfur battery charging and discharging platforms.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such modifications are intended to be included in the scope of the present invention.

Claims (9)

1. A preparation method of an N-doped CNT in-situ coated Co nanoparticle composite material is characterized by comprising the following preparation steps:
(1) dissolving urea, boric acid, polyethylene glycol and cobalt nitrate in water, stirring and mixing uniformly, heating to completely volatilize the solvent, and drying to obtain precursor powder;
(2) carrying out heat treatment on the precursor powder obtained in the step (1) to obtain an N-doped CNT in-situ coated Co nanoparticle composite material;
in the step (1), the mass ratio of the polyethylene glycol to the cobalt nitrate is 0.5: (0.2-0.6).
2. The method of claim 1, wherein the N-doped CNT in-situ coated Co nanoparticle composite material comprises: the mass ratio of the polyethylene glycol to the cobalt nitrate is 0.5: 0.4.
3. The method of claim 1, wherein the N-doped CNT in-situ coated Co nanoparticle composite material comprises: the drying temperature in the step (1) is 60-80 ℃.
4. The method of claim 1, wherein the N-doped CNT in-situ coated Co nanoparticle composite material comprises: the heat treatment in the step (2) is carried out in an argon atmosphere, the heat treatment temperature is 700-900 ℃, and the time is 4-6 hours.
5. An N-doped CNT in-situ coated Co nanoparticle composite material is characterized in that: prepared by the method of any one of claims 1 to 4.
6. The N-doped CNT in-situ coated Co nanoparticle composite material of claim 5, wherein: the diameter of the N-doped CNT in-situ coated Co nanoparticle composite material is 1-1.5 mu m.
7. The use of the N-doped CNT in-situ coated Co nanoparticle composite as claimed in claim 5 or 6 as a lithium-sulphur battery positive electrode material, characterized in that the application process is: and uniformly mixing the N-doped CNT in-situ coated Co nanoparticle composite material with elemental sulfur, heating and preserving heat for reaction, further carrying out heat treatment on the reaction product, and removing redundant S to obtain the lithium-sulfur battery anode material.
8. The use of the N-doped CNT in-situ coated Co nanoparticle composite as claimed in claim 7 as a lithium-sulfur battery positive electrode material, characterized in that: the mass ratio of the N-doped CNT in-situ coated Co nanoparticle composite material to elemental sulfur is 1 (3-4).
9. The use of the N-doped CNT in-situ coated Co nanoparticle composite as claimed in claim 7 as a lithium-sulfur battery positive electrode material, characterized in that: the temperature of the heating and heat preservation reaction is 155-200 ℃, and the time is 12-16 h; the heat treatment is to heat the mixture to 200-250 ℃ at a heating rate of 1-3 ℃/min and keep the temperature for 0.5-2 h under the argon atmosphere.
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