CN110510595A - A kind of preparation method of the N/S codope porous carbon for lithium-sulfur cell - Google Patents

A kind of preparation method of the N/S codope porous carbon for lithium-sulfur cell Download PDF

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CN110510595A
CN110510595A CN201910634778.0A CN201910634778A CN110510595A CN 110510595 A CN110510595 A CN 110510595A CN 201910634778 A CN201910634778 A CN 201910634778A CN 110510595 A CN110510595 A CN 110510595A
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porous carbon
lithium
preparation
sulfur cell
powder
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CN110510595B (en
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刘兴泉
刘金涛
陈俊松
冉淇文
郝帅
李蕾
李�浩
胡友作
肖雨
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University of Electronic Science and Technology of China
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
    • 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
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • 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

Abstract

The invention belongs to inorganic non-metallic technical field of function materials, a kind of preparation method of N/S codope porous carbon for lithium-sulfur cell is specifically provided, carbon matrix precursor is used as using natural biomass materials (especially ginkgo nut pulp), it is from a wealth of sources, low in cost；Using mild nanometer calcium carbonate as carbonization template, it can remove, have fewer environmental impacts in the acid solution of low concentration；Also, entirely preparation is simple, is conducive to industrialized production.The Heteroatom doping porous carbon degree of graphitization with higher that the present invention synthesizes, uniform pore-size distribution, higher specific surface area；Applied to lithium sulfur battery anode material, excellent specific capacity and cyclical stability and high rate performance are presented, can effectively overcome that existing lithium-sulfur cell sulphur positive conductive is poor, in charge and discharge process the defects of the dissolution of the significant volume expansion of active material, serious shuttle effect and polysulfide.

Description

A kind of preparation method of the N/S codope porous carbon for lithium-sulfur cell
Technical field
The invention belongs to inorganic non-metallic technical field of function materials, are related to the preparation of porous carbon lithium sulfur battery anode material Method, N/S codope porous carbon derived from specifically a kind of natural biomass for positive pole material for high-performance lithium-sulfur battery and Preparation method.
Background technique
Lithium-sulfur cell possesses higher theoretical specific capacity (1675mAh g-1) and theoretical energy density (2600Wh kg-1), Its specific capacity and energy density are the three to four-fold or so of current lithium ion battery, are able to satisfy the mankind to growing high-energy The demand of density energy storage device；In addition, sulphur anode has resourceful, low consumption, advantages of environment protection.Therefore, lithium sulphur electricity Pond is considered to be the one of alternative of the most energy storage device of application prospect.However, more in the insulating properties of sulphur anode, charge and discharge process The dissolution in the electrolytic solution of the shuttle effect of sulfide intermediate, polysulfide and the volume expansion of sulphur lead to the work of sulphur anode Property material utilization reduce, eventually lead to battery cycle performance be deteriorated, to constrain the further commercialization of lithium-sulfur cell.
In order to solve the above technical bottleneck, it is commercialized the lithium-sulfur cell with high-energy density early, many researchers The optimization and design of many sulphur anode structures are carried out, wherein maximally efficient method is that design has high specific surface area Porous carbon nominative structure loads more active sulfurs, improves the electric conductivity of sulphur anode and the utilization rate of active material, physical absorption Polysulfide inhibits the volume expansion of sulphur in charge and discharge process.However, polysulfide is the substance of chemical polarity, and porous carbon It is the substance of non-chemical polarity, the adsorption energy of the two is very low, and causing the shuttle effect of polysulfide to improve is not it is obvious that final Cause cycle performance of battery that could not be greatly improved.Therefore, advanced design has chemically compatible porous carbon nominative Structure is the key that improve lithium-sulfur cell electrical property.Heterogeneous doping hetero atom (such as O, N, B, S, P) enters porous carbon structure not It is only capable of creating electric conductivity of more defects to improve porous carbon, and more polar active sites can be created and carry out the more sulphur of chemisorption Compound, to more effectively inhibit the shuttle effect of polysulfide.Biological material is a kind of ideal porous carbon matrix precursor, It is from a wealth of sources, resourceful, and in biological material be rich in all polyfunctional groups, in carbonisation functional group can crack to be formed it is miscellaneous Atom enters carbon structure, and being formed has the heterogeneous heteroatomic porous carbon structure of doping, is the ideal nominative material of sulphur anode.Cause This, biomass carbon material is the hot spot of current research.
Currently, the method for preparing biomass porous carbon material is mainly template and activation carbonizatin method, applied template Mainly there is SiO2、FeCl3、ZnCl2Deng or two or three of combination therein, main activating substance be KOH etc..It answers above The template or activator used, which usually require strong acid (such as HF), to be removed, and activator is highly basic, in carbonisation inevitably Certain damage can be caused to equipment, and strong acid used can cause certain pollution to environment, preparation process is complicated, it is difficult to realize Industrialization.
Summary of the invention
The purpose of the present invention is to provide a kind of preparation method of N/S codope porous carbon for lithium-sulfur cell, preparations The N/S Heteroatom doping porous carbon materials of high-specific surface area, high graphitization degree are obtained, is applied to lithium sulfur battery anode material, shows Excellent specific capacity and cyclical stability and high rate performance, can effectively overcome existing lithium-sulfur cell sulphur positive conductive In difference, charge and discharge process the defects of the dissolution of the significant volume expansion of active material, serious shuttle effect and polysulfide.
To achieve the above object, the technical solution adopted by the present invention are as follows:
A kind of preparation method of the N/S codope porous carbon for lithium-sulfur cell, which comprises the steps of:
Step 1: natural biomass materials are dry, and grind into powder is spare；
Step 2: nanometer calcium carbonate and natural biomass materials powder are weighed respectively according to mass ratio (1~3): 1, after mixing Grinding uniformly, obtains mix powder；
Step 3: mix powder is placed in tube furnace, is carbonized under an argon atmosphere, carburizing temperature 650-950 DEG C, heating rate be 2-5 DEG C/min, soaking time 5-10h；It is cooled to room temperature taking-up, and is regrind, carbonization is obtained and produces Object；
Step 4: it is 6-12h to be reacted, to remove residue in 1~2mol/L hydrochloric acid solution that carbonized product, which is added to concentration, Template and reaction be precipitated calcium；Then it is centrifuged, sediment is cleaned, is dried to obtain porous carbon materials.
Further, in the step 1, natural biomass materials use ginkgo nut pulp.
Further, in the step 2, the particle size of nanometer calcium carbonate is 20~100 nanometers.
Further, in the step 4, cleaning process are as follows: sediment is washed for several times using deionized water, until cleaning Liquid pH value is neutrality；Drying process are as follows: put the precipitate in vacuum oven, at a temperature of 60~90 DEG C be dried in vacuo 6~ 12h。
The beneficial effects of the present invention are:
The present invention provides a kind of preparation method of N/S codope porous carbon for lithium-sulfur cell, using natural biomass Material (especially ginkgo nut pulp) is used as carbon matrix precursor, from a wealth of sources, low in cost；Using mild nanometer calcium carbonate as carbon Change template, can remove, have fewer environmental impacts in the acid solution of low concentration；Also, entire preparation process is simply easy Row, is conducive to industrialized production.The Heteroatom doping porous carbon degree of graphitization with higher that the present invention synthesizes, it is uniform Pore-size distribution, higher specific surface area；The porous carbon is applied to lithium sulfur battery anode material, presents excellent specific capacity With cyclical stability and high rate performance.
Detailed description of the invention
Fig. 1 is the synthetic route chart for the N/S codope porous carbon that the present invention is prepared in embodiment 1.
Fig. 2 is the transmission electron microscope for the N/S codope porous carbon that the present invention is prepared in embodiment 1 and the element of scanning transmission Map ping figure.
Fig. 3 is the first charge-discharge for the porous carbon supported sulphur lithium-sulfur cell of N/S codope that the present invention is prepared in embodiment 1 It can curve (0.1C multiplying power, 25 DEG C).
Fig. 4 is the cycle performance curve of the porous carbon supported sulphur lithium-sulfur cell of N/S codope of 1 preparation in embodiment of the invention (0.1C multiplying power, 25 DEG C).
Fig. 5 is the high rate performance curve of the porous carbon supported sulphur lithium-sulfur cell of N/S codope of 1 preparation in embodiment of the invention (1.5-3.0V, 25 DEG C).
Specific embodiment
In order to better illustrate the summary of the invention of this patent, the present invention is done into one with attached drawing combined with specific embodiments below The detailed description of step.
Embodiment 1
Step 1: it after mature ginkgo nut (natural biomass materials) is collected, is washed with deionized water, removes the peel and decladding, Obtain the pulp of ginkgo nut；Then pulp is freeze-dried, dry pulp is obtained and to be ground into yellow powder standby With；
Step 2: the pulp powder of 1g and the nanometer calcium carbonate of 2g are weighed respectively in mortar, are ground uniformly (about 10min), Obtain mix powder；
Step 3: the above mixture being put into ceramic boat, puts into tube furnace and is carbonized under an argon atmosphere, from room Temperature is warming up to 800 DEG C, and heating rate is 2 DEG C/min, and soaking time 6h is cooled to room temperature taking-up, and regrinds；
Step 4: the powder after grinding being slowly added in the hydrochloric acid solution of 1mol/L, 12h is stirred, is then centrifuged Separation, is washed with deionized 3~4 times, until the pH value of solution is about neutrality 7；Then it puts into vacuum oven, 60 DEG C true The dry 12h of sky, obtains porous carbon materials；
Step 5: by porous carbon and a certain amount of sublimed sulfur ground and mixed (sulfur content is about 80%), and this mixture being put Into in stainless steel closed container, 155 DEG C of reaction 12h obtain sulphur positive electrode, by sulphur positive electrode and Super P and gather inclined fluorine Appropriate N methyl pyrrolidone (NMP) solvent is added after mixing in mass ratio for 8:1:1 for ethylene (PVDF) and ground and mixed uniformly applies Be distributed on an aluminium foil, and be dried, shear, being prepared into working electrode, (face carrying capacity is about 2.5mg/cm2), with lithium metal foil To electrode and reference electrode, to be assembled into button lithium-sulfur cell in glove box, electrochemical property test (voltage is carried out after standing Window: 1.5-3.0V, 0.1C multiplying power).
Test result as shown in Fig. 2~Fig. 5, as Fig. 2 be N/S codope porous carbon prepared by the present invention transmission electron microscope and The element M apping of scanning transmission schemes.As Fig. 3 be the porous carbon supported sulphur lithium-sulfur cell of N/S codope prepared by the present invention for the first time Charge-discharge performance curve (0.1C multiplying power, 25 DEG C).If Fig. 4 is the porous carbon supported sulphur lithium-sulfur cell of N/S codope prepared by the present invention Cycle performance curve (0.1C multiplying power, 25 DEG C).If Fig. 5 is the porous carbon supported sulphur lithium-sulfur cell of N/S codope prepared by the present invention High rate performance curve (1.5-3.0V, 25 DEG C).
Embodiment 2
Step 1: it after mature ginkgo nut (natural biomass materials) is collected, is washed with deionized water, removes the peel and decladding, Obtain the pulp of ginkgo nut；Then pulp is freeze-dried, dry pulp is obtained and to be ground into yellow powder standby With；
Step 2: the pulp powder of 1g and the nanometer calcium carbonate of 3g are weighed respectively in mortar, are ground uniformly (about 10min), Obtain mix powder；
Step 3: the above mixture being put into ceramic boat, puts into tube furnace and is carbonized under an argon atmosphere, from room Temperature is warming up to 850 DEG C, and heating rate is 3 DEG C/min, and soaking time 6h is cooled to room temperature taking-up, and regrinds；
Step 4: the powder after grinding being slowly added in the hydrochloric acid solution of 1mol/L, 12h is stirred, is then centrifuged Separation, is washed with deionized 3~4 times, until the pH value of solution is about neutrality 7；Then it puts into vacuum oven, 80 DEG C true The dry 12h of sky, obtains porous carbon materials；
Step 5: by porous carbon and a certain amount of sublimed sulfur ground and mixed (sulfur content is about 80%), and this mixture being put Into in stainless steel closed container, 155 DEG C of reaction 12h obtain sulphur positive electrode, by sulphur positive electrode and Super P and gather inclined fluorine Appropriate N methyl pyrrolidone (NMP) solvent is added after mixing in mass ratio for 8:1:1 for ethylene (PVDF) and ground and mixed uniformly applies Be distributed on an aluminium foil, and be dried, shear, being prepared into working electrode, (face carrying capacity is about 2.5mg/cm2), with lithium metal foil To electrode and reference electrode, to be assembled into button lithium-sulfur cell in glove box, electrochemical property test (voltage is carried out after standing Window: 1.5-3.0V, 0.1C multiplying power).
Test result shows: the lithium-sulfur cell still has preferable chemical property.
The above description is merely a specific embodiment, any feature disclosed in this specification, except non-specifically Narration, can be replaced by other alternative features that are equivalent or have similar purpose；Disclosed all features or all sides Method or in the process the step of, other than mutually exclusive feature and/or step, can be combined in any way.

Claims (4)

1. a kind of preparation method of the N/S codope porous carbon for lithium-sulfur cell, which comprises the steps of:
Step 1: natural biomass materials are dry, and grind into powder is spare；
Step 2: according to mass ratio (1~3): 1 weighs nanometer calcium carbonate and natural biomass materials powder respectively, grinds after mixing Uniformly, mix powder is obtained；
Step 3: mix powder is placed in tube furnace, is carbonized under an argon atmosphere, carburizing temperature be 650~950 DEG C, Heating rate is 2~5 DEG C/min, and soaking time is 5~10h；It is cooled to room temperature taking-up, and is regrind, carbonized product is obtained；
Step 4: it is to react 6~12h in 1~2mol/L hydrochloric acid solution that carbonized product, which is added to concentration,；Then centrifugation point is carried out From being cleaned to sediment, be dried to obtain porous carbon materials.
2. preparation method according to claim 1, which is characterized in that in the step 1, natural biomass materials use ginkgo Fruit pulp.
3. preparation method according to claim 1, which is characterized in that in the step 2, the particle size of nanometer calcium carbonate is 20~100 nanometers.
4. preparation method according to claim 1, which is characterized in that in the step 4, cleaning process are as follows: use deionization Water washs for several times sediment, until cleaning solution pH value is neutrality；Drying process are as follows: it puts the precipitate in vacuum oven, 6~12h is dried in vacuo at a temperature of 60~90 DEG C.
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CN114671425A (en) * 2022-01-07 2022-06-28 齐鲁工业大学 Iodine-doped biomass-derived porous carbon composite material and preparation method thereof
CN115353090A (en) * 2022-08-11 2022-11-18 华南理工大学 Novel biomass hard carbon sodium ion battery material and preparation method thereof

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CN114671425A (en) * 2022-01-07 2022-06-28 齐鲁工业大学 Iodine-doped biomass-derived porous carbon composite material and preparation method thereof
CN115353090A (en) * 2022-08-11 2022-11-18 华南理工大学 Novel biomass hard carbon sodium ion battery material and preparation method thereof

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