CN106328895B - A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method - Google Patents
A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method Download PDFInfo
- Publication number
- CN106328895B CN106328895B CN201610812049.6A CN201610812049A CN106328895B CN 106328895 B CN106328895 B CN 106328895B CN 201610812049 A CN201610812049 A CN 201610812049A CN 106328895 B CN106328895 B CN 106328895B
- Authority
- CN
- China
- Prior art keywords
- silkworm excrement
- stage porous
- spch
- porous charcoal
- sulphur
- 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.)
- Active
Links
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
-
- 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
- H01M10/0525—Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
-
- 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
- H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
- H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
-
- 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 discloses a kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive poles and preparation method thereof.First by silkworm excrement and ZnCl2Mixing is placed in high temperature process furnances, and silkworm excrement multi-stage porous charcoal SPCH is obtained by the reaction in heating under a shielding gas；Sulphur powder is subsequently poured into be allowed to not be in direct contact with SPCH；Vacuumize, seal after be put into drying box, temperature reaction obtains SPCH/S1Composite material；It places it in hypo solution and stands again, then hydrochloric acid solution is added dropwise and carries out the secondary load 2~5h of reaction of Salmon-Saxl of chemical deposition, after centrifugal filtration, SPCH/S composite materials are obtained in drying；It is coated with graphene oxide again and restores to obtain G-SPCH/S composite sulfur anodes by microwave radiation.The present invention loads sulphur using vacuum-steam method, chemical solution deposition, is remarkably improved sulphur adsorption and uniform dispersion on carrier, after graphene coated, and battery cycle life can be improved.
Description
Technical field
The invention belongs to materials chemistries and electrochemical technology field, and in particular to porous carbon material and its lithium-sulfur cell material
And preparation method thereof.
Background technology
The excessive exploitation and a large amount of consumption of fossil energy have caused increasingly serious global energy crisis and environmental problem, sternly
The living environment of the mankind and the sustainable development of social economy have been threatened again.Therefore, accelerate that especially cleaned to new energy can be again
The development and utilization of the raw energy is top priority and severe challenge of the human society in the facing of new century.It recycles available
Secondary cell is the excellent energy storage device of various regenerative resources (such as solar energy, wind energy, tide energy), is that the following cleaning can be again
The indispensable important composition of the raw energy, there is great social demand.
In recent years, lithium-sulfur cell is concerned as the lithium secondary battery of high-energy density of new generation.Its theory compares energy
Amount may be up to 2600Wh/kg, and 6-7 times is higher by than lithium ion battery energy density, can support a kart continuation of the journey 500-
800km or more, thus be concerned, and be considered as one of following most promising energy-storage battery system.
The performance of sulphur positive electrode is the key that determine lithium-sulfur cell quality height in lithium-sulfur cell.However, being limited to sulphur
And its it is produced among the electric conductivity that discharging product lithium sulfide is poor, and a series of more lithium sulfides formed in charge and discharge process
Object is soluble in the shortcomings of organic electrolyte, and that there are still sulphur anode utilization rates is relatively low (especially under high current density for lithium-sulfur cell
Charge and discharge) and the problems such as poor circulation, become the maximum bottleneck for hindering lithium-sulfur cell practical application.
Among if sulphur could are homogeneously dispersed in the form of small particle size to a kind of porous material with good conductivity, a side
Face can effectively improve the utilization rate of sulphur；On the other hand, it is acted on using the adsorption of conductive carrier and can effectively be inhibited again
The loss of sulphur and its discharging product (more lithium sulfides) on anode pole piece.Therefore, by sulphur with carbon material is compound can prepare height
Capacity and the excellent anode composite material of lithium sulfur battery of cycle performance.Silkworm excrement is the main waste of silkworm industry, is passed through in rural area
Chang Suiyi discarding lead to environmental pollution, from Electron microscope from known to its with natural three-dimensional drape structure and phosphorus content height,
High-ratio surface multiporous biological charcoal can be obtained through high temperature cabonization and activation.
Currently, people mostly use step melting diffusion method injects formation lithium sulphur anode composite wood in load sulfur materials by sulphur component
Material.There are following problems for the method：(1) sulphur is bad with the wellability of porous material hole wall in the molten state, it tends to be difficult to
Go deep into inside duct in especially micropore hole, and blocks duct；(2) sulphur component and porous material hole wall binding force are relatively low, dispersion
It is uneven.These two aspects largely affects the high rate performance of composite material entirety, while being easy to cause composite material
Middle utilization efficiency is not high, and the discharge capacity of battery reduces；In addition sulphur component is not easy to diffuse into micropore canals, reduces it and carries sulphur
The adsorption of material causes the polysulfide that reaction generates to be easier to be dissolved into organic electrolyte, accelerates lithium-sulfur cell
Capacity attenuation speed.
Invention content
The present invention carries that sulphur is uneven and adsorption capacity is weak for existing porous material and leads to composite material poor circulation etc.
Problem is provided a kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method thereof, is inhaled using gas phase steam
Sulphur component is supported on nano particle size in the duct of silkworm excrement multi-stage porous charcoal by the process of attached-chemical solution deposition, then by molten
Liquid method coats graphene oxide sheet, then graphene oxide sheet is reduced into graphene by microwave irradiation, obtains the long-life
Carbon sulphur composite positive pole.
The purpose of the present invention is achieved through the following technical solutions：
A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole, the porous carrier of the material have mesoporous (2~
50nm) and micropore (<2nm) two kinds of ducts, micropore to sulfur molecule have strong adsorption, and mesoporous be electronics, ion with
And the discharging product of sulphur and sulphur provides quick diffusion admittance；The BET specific surface area of obtained SPCH materials is in 1200m2/ g with
On, micropore average pore size existsThe average pore size of mesoporous existsAfter graphene film coats, material follows
Ring performance, which has, to be obviously improved.Obtained SPCH/S composite materials are up to 1000mAh/g or more in 1.0C discharge capacities, and
Specific discharge capacity at 1.0C after 200 circle of cycle is up to 800mAh/g or more, and capacity retention ratio is up to 90% or more.
The preparation method of the graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole of the present invention, includes the following steps,
(1) preparation of silkworm excrement multi-stage porous charcoal：By silkworm excrement and ZnCl2Powder mixes, and is placed in high temperature process furnances, leads to protection gas
After body purging, it is heated to 300-700 DEG C and carries out that silkworm excrement multi-stage porous charcoal is obtained by the reaction；It is denoted as SPCH；
(2) silkworm excrement multi-stage porous charcoal uploads sulphur：First silkworm excrement multi-stage porous carbon powder is put into quartz ampoule, then pours into sulphur powder into stone
Ying Guanzhong is not in direct contact with silkworm excrement multi-stage porous charcoal；Vacuumize, seal after be put into drying box, be warming up to 120~160 DEG C, then
Constant temperature takes out cooled to room temperature after keeping 8~20h, obtains SPCH/S1Composite material；
(3) secondary load sulphur：By SPCH/S1Composite material is placed in hypo solution and stands, then hydrochloric acid solution is added dropwise
The secondary load 2~5h of reaction of Salmon-Saxl of chemical deposition is carried out, after centrifugal filtration, it is multiple to obtain graphene coated silkworm excrement multi-stage porous charcoal sulphur in drying
Positive electrode is closed, SPCH/S composite materials are denoted as.
(4) graphene coated process：SPCH/S composite materials are placed in the aqueous solution of graphene oxide, SPCH/S and oxygen
The mass ratio of graphite alkene is in 5-19:1, stirring after a certain period of time, sample taking-up is placed in microwave reactor and is heated, microwave
Reaction temperature is controlled at 100-150 DEG C, reaction time 5-15min, and it is compound just to obtain graphene coated silkworm excrement multi-stage porous charcoal sulphur
Pole material G-SPCH/S.
As the further preferred of scheme, step (1) the high temperature carburizing reagent time is 0.5~5h, protectiveness gas
Nitrogen, the inert gases such as argon gas can be used in body；ZnCl2Mass ratio with silkworm excrement is (1~6):1.
As the further preferred of scheme, vacuum degree≤100Pa in control quartz ampoule in the step (2)., drying box adopts
With can temperature programmed control drying box, specific temperature control process：
(a) temperature-rise period：With the heating rate of 0.5~2.0 DEG C/min 120~160 DEG C are risen to from room temperature；
(b) thermostatic process：It is placed in 120~160 DEG C of 10~15h of holding；
(c) temperature-fall period：It is taken out out of drying box immediately after thermostatic process, cooled to room temperature.
As the further preferred of scheme, hypo solution and SPCH/S in the step (3)1The matter of composite material
Amount is than being 4~10:1, time of repose is 5~10h.
As the further preferred of scheme, the molar ratio of hydrochloric acid and sodium thiosulfate is 3~11 in the step (3)：1,
A concentration of 0.03~0.20mol/L of sodium thiosulfate can be used, concentration of hydrochloric acid is 3~10wt%.
As the further preferred of scheme, the reaction temperature of microwave is controlled at 100-150 DEG C in the step (4), reaction
Time is 5-15min.
The principle of the present invention：Keep gaseous sulfur Molecular Adsorption silkworm excrement multistage by vapor sorption mode under vacuum conditions first
On the most strong adsorption site of hole Carbon Materials, sulphur microcrystals is formed in the micropore canals of silkworm excrement multi-stage porous charcoal, obtains silkworm excrement multistage
Hole charcoal sulphur SPCH/S1Composite material.Recycle chemical solution deposition by SPCH/S1Composite material is placed in Na2S2O3In solution, delay
It is slow that hydrochloric acid solution is added dropwise, so that sulphur is slowly precipitated on the existing sulphur nucleus of silkworm excrement multi-stage porous charcoal, forms sulphur Load Balanced and absorption
The strong silkworm excrement multi-stage porous charcoal sulphur composite material of power, then outer layer is wrapped up in into deposited graphene, sulphur component outflow can be significantly inhibited, to be promoted
The high rate capability of composite material and long-acting cycle performance.
The graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole of the present invention recycles the electric discharge after 220 circles at 1.0C
Specific capacity is up to 850-890mAh/g, and capacity retention ratio is up to 90% or more, hence it is evident that is carried obtained by sulphur higher than directly melting diffusion
2~3 times of uncoated charcoal sulphur composite positive pole and conventional lithium-ion battery material specific capacity.
Compared with prior art, the present invention is advantageous in that：
(1) carrier used in the present invention is silkworm excrement multi-stage porous charcoal, belongs to waste utilization, is derived from a wealth of sources and of low cost,
Reaming one-step method is completed, and process is simple and environmentally friendly.
(2) structure for the fold having using silkworm excrement itself is carbon source, and the more of three-dimensional network intercommunication can be formed by reaming
Grade pore structure, micropore surface are conducive to improve the adsorption capacity to sulphur, and mesoporous then can provide conveying and lead to for lithium ion and electrolyte
Road reduces the diffusional resistance of lithium ion and electrolyte.
(3) active sulphur component can be equably carried in the duct of SPCH by the present invention using vapor diffusion, can be made
Sulphur component occupies most strong adsorption site and forms small S crystal seeds, then can be supported on more S by force by chemical solution deposition
Adsorption potential, this aspect can effectively improve the adhesive force of sulphur component and carrier and the contact area of sulphur component and conductive hole wall,
On the other hand it also can effectively avoid melting diffusion method that duct is brought to block linear, and then improve the utilization ratio of sulphur, while energy
Obtain the cycle performance of long-acting cycle.
(4) graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole of the invention, the graphene shell energy of outer layer
The excessive of sulphur component is effectively prevented, makes battery that there is higher high rate performance and excellent cycle performance, presents good work
Industry application prospect.
(5) preparation method of the invention is simple to operation, is suitble to large-scale industrial production.
Description of the drawings
Fig. 1 is the SEM of silkworm excrement；
Fig. 2 is the SEM figures of silkworm excrement multi-stage porous charcoal；
Fig. 3 is the SEM figures of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole embodiment 1；
Fig. 4 is the thermal gravimetric analysis curve figure of the embodiment of the present invention 1 and SPC/S composite materials；
After Fig. 5 embodiment of the present invention 1 activates 2 circles at 0.5C (840mA/g), the cycle under 1.0C (1680mA/g) multiplying power
Performance map.
Specific implementation mode
The present invention will be further described with reference to the accompanying drawings and examples, but the scope of protection of present invention is not
It is confined to the range of embodiment statement.
Embodiment 1
A kind of preparation method of graphene coated silkworm excrement multi-stage porous sulphur composite positive pole, includes the following steps,
(1) preparation of silkworm excrement multi-stage porous
In N2By 10.0g Faeces bombycis and 10.0g ZnCl in atmosphere2Powder is raised to 700 DEG C with the heating rate of 2 DEG C/min,
And room temperature is cooled to after holding 0.5h at 700 DEG C, silkworm excrement multi-stage porous charcoal is obtained, SPCH is denoted as.
(2) vacuum-steam method uploads sulphur in silkworm excrement multi-stage porous
First 0.3g SPCH powder is laid in Noah's ark, and Noah's ark is slowly pushed into the middle part of quartz ampoule.1g sulphur powders are fallen
Enter in quartz ampoule, is not in direct contact with carbonization SPCH；Vacuumize after (vacuum degree is in≤100Pa), sealing that put it into can program
In the drying box of temperature control, 120 DEG C are warming up to according to the heating rate with 0.5 DEG C/min, constant temperature takes out natural cooling after keeping 20h
To room temperature, SPCH/S is obtained1Composite material.
(3) chemical solution deposition is in SPCH/S1Secondary load sulphur on composite material
By 0.1g SPCM/S1Composite material, which is placed in the hypo solution of 100mL, stands 5h, sodium thiosulfate
Concentration is in 0.03mol/L；Then the hydrochloric acid solution 12mL that concentration 3wt% is slowly added dropwise fully reacts 2h；After centrifugal filtration, 80
It is dried for standby at DEG C, sample is labeled as SPCH/S composite materials.
(4) graphene coated process：0.57g SPCH/S composite materials are placed in containing the water-soluble of 100mg graphene oxides
In liquid, after stirring certain 2h times, sample taking-up is placed in microwave reactor and is heated, the reaction temperature of microwave is controlled 100
DEG C, reaction time 15min obtains the SPCH/S composite sulfur positive electrodes of graphene coated.
Embodiment 2
A kind of preparation method of graphene coated silkworm excrement multi-stage porous sulphur composite positive pole, includes the following steps,
(1) preparation of silkworm excrement multi-stage porous
In N2By 10.0g Faeces bombycis and 30.0g ZnCl in atmosphere2Powder is raised to 700 DEG C with the heating rate of 5 DEG C/min,
And room temperature is cooled to after holding 1.0h at 700 DEG C, silkworm excrement multi-stage porous is obtained, SPCH is denoted as.
(2) vacuum-steam method uploads sulphur in silkworm excrement multi-stage porous
First 1.0g silkworm excrement multi-stage porous SPCH powder is laid in Noah's ark, and Noah's ark is slowly pushed into the middle part of quartz ampoule.
The sulphur powder of 2g is poured into quartz ampoule, is not in direct contact with silkworm excrement multi-stage porous charcoal SPCH；Vacuumize (vacuum degree is in≤100Pa),
140 DEG C can be warming up to, constant temperature in the drying box of temperature programmed control according to the heating rate with 1.0 DEG C/min by being put it into after sealing
Cooled to room temperature is taken out after keeping 10h, obtains SPCH/S1Composite material.
(3) chemical solution deposition is in SPCH/S1Secondary load sulphur on composite material
By 0.6g SPCH/S1Composite material, which is placed in the hypo solution of 200mL, stands 7h, sodium thiosulfate
Concentration is in 0.12mol/L；Then the hydrochloric acid solution 120mL that concentration 6wt% is slowly added dropwise fully reacts 4h；After centrifugal filtration,
It is dried for standby at 80 DEG C, sample is labeled as SPCH/S composite materials.
(4) graphene coated process：1.0g SPCH/S composite materials are placed in containing the water-soluble of 100mg graphene oxides
In liquid, after stirring certain 3h times, sample taking-up is placed in microwave reactor and is heated, the reaction temperature of microwave is controlled 110
DEG C, reaction time 12min obtains the SPCH/S composite sulfur positive electrodes of graphene coated.
Embodiment 3
A kind of preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole, includes the following steps,
(1) preparation of micropore silkworm excrement
In N2By 10.0g Faeces bombycis and 40.0g ZnCl in atmosphere2Powder is raised to 600 DEG C with the heating rate of 3 DEG C/min,
And room temperature is cooled to after holding 2.0h at 600 DEG C, silkworm excrement multi-stage porous charcoal is obtained, SPCH is denoted as.
(2) vacuum-steam method uploads sulphur in silkworm excrement multi-stage porous charcoal
First 2.0g silkworm excrement multi-stage porous charcoal SPCH powder is laid in Noah's ark, and Noah's ark is slowly pushed into quartz ampoule
Portion.A certain amount of sulphur powder is poured into quartz ampoule, is not in direct contact with silkworm excrement multi-stage porous charcoal SPCH；Vacuumize (vacuum degree≤
100Pa), 160 can be warming up in the drying box of temperature programmed control according to the heating rate with 2.0 DEG C/min by being put it into after sealing
DEG C, constant temperature takes out cooled to room temperature after keeping 8h, obtains SPCH/S1Composite material.
(3) chemical solution deposition is in SPCH/S1Secondary load sulphur on composite material
By 1.0g SPCH/S1Composite material, which is placed in the hypo solution of 300mL, stands 10h, sodium thiosulfate
Concentration is in 0.20M；Then the hydrochloric acid solution 240mL that concentration 10wt% is slowly added dropwise fully reacts 5h；After centrifugal filtration, at 80 DEG C
Under be dried for standby, sample be labeled as SPCH/S composite materials.
(4) graphene coated process：1.8g SPCH/S composite materials are placed in containing the water-soluble of 100mg graphene oxides
In liquid, after stirring certain 1h times, sample taking-up is placed in microwave reactor and is heated, the reaction temperature of microwave is controlled 150
DEG C, reaction time 5min obtains the SPCH/S composite sulfur positive electrodes of graphene coated.
Embodiment 4
A kind of preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole, includes the following steps,
(1) preparation of silkworm excrement multi-stage porous charcoal SPCH
In N2By 10.0g Faeces bombycis and 50.0g ZnCl in atmosphere2Powder is raised to 500 DEG C with the heating rate of 6 DEG C/min,
And room temperature is cooled to after holding 3.0h at 500 DEG C, obtain silkworm excrement multi-stage porous charcoal SPCH.
(2) vacuum-steam method uploads sulphur in silkworm excrement multi-stage porous charcoal
First the ends 0.6g silkworm excrement multi-stage porous charcoal SPCH are laid in Noah's ark, and Noah's ark is slowly pushed into the middle part of quartz ampoule.
A certain amount of sulphur powder is poured into quartz ampoule, is not in direct contact with silkworm excrement multi-stage porous charcoal SPCH；Vacuumize (vacuum degree≤
100Pa), 130 can be warming up in the drying box of temperature programmed control according to the heating rate with 1.0 DEG C/min by being put it into after sealing
DEG C, constant temperature takes out cooled to room temperature after keeping 15h, obtains SPCH/S1Composite material.
(3) chemical solution deposition is in SPCH/S1Secondary load sulphur on composite material
By 0.3g SPCH/S1Composite material, which is placed in the hypo solution of 150mL, stands 6h, sodium thiosulfate
Concentration is in 0.07M；Then the hydrochloric acid solution 60mL that concentration 4wt% is slowly added dropwise fully reacts 3h；After centrifugal filtration, at 80 DEG C
It is dried for standby, sample is labeled as SPCH/S composite materials.
(4) graphene coated process：1.8g SPCH/S composite materials are placed in containing the water-soluble of 100mg graphene oxides
In liquid, after stirring certain 1h times, sample taking-up is placed in microwave reactor and is heated, the reaction temperature of microwave is controlled 130
DEG C, reaction time 10min obtains the SPCH/S composite sulfur positive electrodes of graphene coated.
Embodiment 5
A kind of preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole, includes the following steps,
(1) preparation of silkworm excrement multi-stage porous charcoal SPCH
In N2By 10.0g Faeces bombycis and 60.0g ZnCl in atmosphere2Powder is raised to 300 DEG C with the heating rate of 4 DEG C/min,
And room temperature is cooled to after holding 5.0h at 300 DEG C, obtain silkworm excrement multi-stage porous charcoal SPCH.
(2) vacuum-steam method uploads sulphur in silkworm excrement multi-stage porous charcoal SPCH
First 1.5g silkworm excrement multi-stage porous charcoal SPCH powder is laid in Noah's ark, and Noah's ark is slowly pushed into quartz ampoule
Portion.A certain amount of sulphur powder is poured into quartz ampoule, is not in direct contact with silkworm excrement multi-stage porous charcoal SPCH；Vacuumize (vacuum degree≤
100Pa), 150 can be warming up in the drying box of temperature programmed control according to the heating rate with 2.0 DEG C/min by being put it into after sealing
DEG C, constant temperature takes out cooled to room temperature after keeping 13h, obtains SPCH/S1Composite material.
(3) chemical solution deposition is in SPCH/S1Secondary load sulphur on composite material
By 0.8g SPCH/S1Composite material, which is placed in the hypo solution of 250mL, stands 9h, sodium thiosulfate
Concentration is in 0.18M；Then the hydrochloric acid solution 190mL that concentration 9wt% is slowly added dropwise fully reacts 4h；After centrifugal filtration, at 80 DEG C
Under be dried for standby, sample be labeled as SPCH/S composite materials.
(4) graphene coated process：1.9g SPCH/S composite materials are placed in containing the water-soluble of 100mg graphene oxides
In liquid, after stirring certain 3h times, sample taking-up is placed in microwave reactor and is heated, the reaction temperature of microwave is controlled 120
DEG C, reaction time 5min obtains the SPCH/S composite sulfur positive electrodes of graphene coated.
Material properties test：
(1) surface topography of G-SPCH/S composite materials
Embodiment 1, silkworm excrement multi-stage porous charcoal and silkworm excrement prepared by the present invention carries out electron-microscope scanning, obtains Fig. 1~Fig. 3's
SEM schemes.
Fig. 1 is the SEM photograph of Faeces bombycis, and Fig. 2 is the SEM photograph of silkworm excrement multi-stage porous charcoal SPCH, and Fig. 3 is produced by the present invention
The SEM photograph of embodiment 1.
It can be seen that compared with Faeces bombycis in comparison diagram 1 and Fig. 2, silkworm excrement multi-stage porous charcoal wrinkled surface fades away, and occurs
Very abundant duct and channel design, channel interior are also may be seen indistinctly more tiny duct, and multiple aperture hole is showed
Road net distribution pattern.This structure is advantageous to the load of S.The surfaces Fig. 3 are obviously covered with one layer of lamellar material, as stone
Generated structure after black alkene cladding.
(2) silkworm excrement multi-stage porous charcoal, SPC/S1And the pore structure parameter of SPC/S composite materials
Using the ASAP-2020 specific surface pore-size distribution instrument of Micro companies of U.S. production to silkworm excrement multi-stage porous SPC, SPC/
S1And the pore structure of SPC/S composite materials is characterized, the results are shown in Table 1.
The pore structure parameter of 1 silkworm excrement multi-stage porous charcoal of table, SPCM/S and G-SPCM/S
As can be seen from Table 1, silkworm excrement multi-stage porous charcoal SPCH has higher specific surface area, and Langmuir and BET compare table
Area is respectively 955 and 1202m2/ g, total pore volume 0.42cm3/g.This explanation is after high-temperature activation reacts, Faeces bombycis duct
Interior oxygen-containing group and some tar components are removed, while activator ZnCl2Have it is strong take hydrogen by force and take oxygen function by force, by silkworm
The multi-stage porous pore passage structure of micropore and mesoporous is etched on husky internal channel.The material is that a kind of having multi-stage porous (in/micropore) carbon
Material, wherein micropore can form stronger adsorption to sulphur and polysulfide, help to improve following for sulphur composite material
Ring stability；Hollow sections then can provide transfer passage for lithium ion and electrolyte, reduce the expansion of lithium ion and electrolyte
Resistance is dissipated, the high rate performance of battery is improved.
Significantly declined by the specific surface area of SPCH/S after steaming process and further chemical solution deposition load sulphur,
The only surplus 199m of Langmuir specific surface areas2/g；Its Kong Rong also significantly declines, only the 26% of the holes SPCH appearance；In addition, micropore hole
Hold and micropore specific area significantly declines, this surface sulphur component is from the exit orifice of silkworm excrement multi-stage porous charcoal (outside connection particle
The macropore on surface is mesoporous) it is diffused among endoporus.
(3) thermogravimetric curve of G-SPCH/S composite materials
It is multiple to the SPC/S prepared by the present invention using the STA449C pattern synthesis thermal analyzer of German NETZSCH companies production
Condensation material carries out heat stability testing, and test condition is：Nitrogen protection, heating rate be 10 DEG C/min, temperature elevating range be 100~
420℃.Test results are shown in figure 3.
From fig. 4, it can be seen that weightlessness takes place at 265 DEG C in embodiment 1 prepared by the present invention, to weight at 362 DEG C
It no longer changes, weightlessness terminates, and weight-loss ratio is about 62.0%.Weight-loss ratio corresponds to the sulfur content of composite material, i.e., this is multiple
The sulfur content of condensation material is about 62.0%.Contrast material SCPH/S, the temperature that sulphur overflows after graphene coated are increased.
It can be seen that preparation method of the present invention is conducive to obtain the composite positive pole of high sulfur content, while the evaporation temperature of S
Degree is higher to illustrate that the adsorption of S and silkworm excrement multi-stage porous charcoal are stronger.
(4) chemical property of G-SPCH/S composite materials
After Fig. 5 shows that one G-SPCH/S composite materials of the embodiment of the present invention activate 4 circles at 0.2C (334mA/g),
Cycle performance figure under 1.0C (1680mA/g) multiplying power.As shown, after material recycles 200 circles at 1.0C, discharge specific volume
Amount is still up to 837mAh/g, and capacity retention ratio is up to 90.5%.This explanation, G-SPCH/S composite materials are in the condition tested
Higher coulombic efficiency is all had, this also illustrates that the combination of S and carrier silkworm excrement multi-stage porous charcoal is more close, while silkworm excrement multi-stage porous
Charcoal also shows more excellent electric conductivity.
Show that electric discharge of the G-SPCH/S composite materials under different multiplying obtained by five kinds of embodiments of the present invention is held in table 2
Amount.As seen from the table, in scope of experiment according to the present invention obtained G-SPCH/S composite materials high rate performance compared with
It is excellent.Specific discharge capacity of the battery under 3.0 and 6.0C is up to 821-873 and 665-725mAh/g respectively；It can be seen that material
The cyclo-stationary for expecting the material in tested multiplying power change procedure has higher specific discharge capacity under high magnification.This with
The big channel of sulfur-donor silkworm excrement multi-stage porous charcoal is related to the quickly conduction of lithium ion with electronics, and the outer graphene wrapped up in is promoted in addition
The electric conductivity of positive electrode entirety, and then improve the high rate performance of material.
Discharge capacity of the G-SPCH/S composite materials under different multiplying obtained by 2 five kinds of embodiments of table
Claims (9)
1. a kind of preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole, it is characterised in that：Including as follows
Step,
(1) preparation of silkworm excrement multi-stage porous charcoal：By silkworm excrement and ZnCl2Powder mixes, and is placed in high temperature process furnances, logical protective gas is blown
After sweeping, silkworm excrement multi-stage porous charcoal SPCH is obtained by the reaction in heating；
(2) silkworm excrement multi-stage porous charcoal uploads sulphur：First silkworm excrement multi-stage porous charcoal is put into quartz ampoule, then pours into sulphur powder into quartz ampoule,
It is not in direct contact with silkworm excrement multi-stage porous charcoal；Vacuumize, seal after be put into drying box, be warming up to 120~160 DEG C, then constant temperature protect
Cooled to room temperature is taken out after holding 8~20 h, obtains SPCH/S1Composite material；
(3) secondary load sulphur：By SPCH/S1Composite material is placed in hypo solution and stands, then hydrochloric acid solution is added dropwise
It learns and deposits secondary 2~5 h of load reaction of Salmon-Saxl, after centrifugal filtration, then dry to obtain silkworm excrement multi-stage porous composite sulfur positive electrode SPCH/S；
(4) graphene coated process：Silkworm excrement multi-stage porous composite sulfur positive electrode SPCH/S is placed in the aqueous solution of graphene oxide
In, the mass ratio of silkworm excrement multi-stage porous composite sulfur positive electrode SPCH/S and graphene oxide is in 5-19:1, after being stirred, set
Reaction is heated in microwave reactor, obtains graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole G-SPCH/S；The material
Material is up to 1000 mAh/g or more in 1.0 C discharge capacities, and the specific discharge capacity at 1.0 C after 200 circle of cycle is up to
800mAh/g or more, capacity retention ratio are up to 90% or more.
2. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：Heating reaction temperature is 300-700 DEG C in the step (1), and the time is 0.5 ~ 5 hour.
3. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：ZnCl in the step (1)2Mass ratio with silkworm excrement is 1~6:1.
4. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：The step（2）The Pa of vacuum degree in middle quartz ampoule≤100.
5. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：The step（2）Middle drying box using can temperature programmed control drying box, specific temperature control process：
(a) temperature-rise period：With the heating rate of 0.5~2.0 DEG C/min 120~160 DEG C are risen to from room temperature；
(b) thermostatic process：It is placed in 120~160 DEG C of 10~15 h of holding；
(c) temperature-fall period：It is taken out out of drying box immediately after thermostatic process, cooled to room temperature.
6. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：Hypo solution and SPCH/S in the step (3)1The mass ratio of composite material is 4 ~ 10: 1.
7. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1 or 6,
It is characterized in that：The molar ratio of hydrochloric acid and sodium thiosulfate is 3~11 in the step (3)：1.
8. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：A concentration of 0.03~0.20mol/L of sodium thiosulfate in the step (3)；Concentration of hydrochloric acid is in the step (3)
3~10 wt%.
9. the preparation method of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole according to claim 1, special
Sign is：At 100-150 DEG C, the reaction time is 5-15 min for the reaction temperature control of microwave in the step (4).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610812049.6A CN106328895B (en) | 2016-09-09 | 2016-09-09 | A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610812049.6A CN106328895B (en) | 2016-09-09 | 2016-09-09 | A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN106328895A CN106328895A (en) | 2017-01-11 |
| CN106328895B true CN106328895B (en) | 2018-10-30 |
Family
ID=57787583
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610812049.6A Active CN106328895B (en) | 2016-09-09 | 2016-09-09 | A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN106328895B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018170241A1 (en) * | 2017-03-15 | 2018-09-20 | Graphene Technologies, Inc. | Composites including unimpregnated cellular carbon nanostructures |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102751494A (en) * | 2012-07-09 | 2012-10-24 | 广州市香港科大***研究院 | Preparation method of novel porous skeleton MIL-101(Cr)@S/graphene composite material for cathode of lithium sulfur battery |
| CN103094535A (en) * | 2013-01-21 | 2013-05-08 | 北京化工大学 | Sulfur/carbon porous nano composite material and preparation method and application thereof |
| CN103531759A (en) * | 2013-09-23 | 2014-01-22 | 广州市香港科大***研究院 | Two-step adsorption preparation method of high magnification sulphur/mesoporous and microporous carbon HAC (honeycomb activated carbon) lithium sulphur battery anode composite material |
| CN105826523A (en) * | 2016-03-17 | 2016-08-03 | 北京理工大学 | Lithium-sulfur battery positive pole material and preparation method thereof |
-
2016
- 2016-09-09 CN CN201610812049.6A patent/CN106328895B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102751494A (en) * | 2012-07-09 | 2012-10-24 | 广州市香港科大***研究院 | Preparation method of novel porous skeleton MIL-101(Cr)@S/graphene composite material for cathode of lithium sulfur battery |
| CN103094535A (en) * | 2013-01-21 | 2013-05-08 | 北京化工大学 | Sulfur/carbon porous nano composite material and preparation method and application thereof |
| CN103531759A (en) * | 2013-09-23 | 2014-01-22 | 广州市香港科大***研究院 | Two-step adsorption preparation method of high magnification sulphur/mesoporous and microporous carbon HAC (honeycomb activated carbon) lithium sulphur battery anode composite material |
| CN105826523A (en) * | 2016-03-17 | 2016-08-03 | 北京理工大学 | Lithium-sulfur battery positive pole material and preparation method thereof |
Non-Patent Citations (2)
| Title |
|---|
| "Graphene-coated mesoporous carbon/sulfur cathode with enhanced cycling stability";X.Y.Zhao等;《Electrochimica Acta》;20131006;第113卷;第256-262页 * |
| "Silkworms’ feces-based activated carbons as cheap adsorbents for removal of cadmium and methylene blue from aqueous solutions";Gamal M.S. ElShafei等;《Chemical Engineering Research and Design》;20140331;第92卷;第461-470页 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN106328895A (en) | 2017-01-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Du et al. | Porous nanostructured ZnCo2O4 derived from MOF-74: High-performance anode materials for lithium ion batteries | |
| CN112490446B (en) | Preparation method of Co-CNT @ CF three-dimensional self-supporting lithium-sulfur battery positive electrode material | |
| CN107221654B (en) | Three-dimensional porous nest-shaped silicon-carbon composite negative electrode material and preparation method thereof | |
| CN105932234A (en) | Doped porous carbon spheres used for negative electrode material of sodium ion battery and preparation method for doped porous carbon spheres | |
| CN108649190A (en) | Vertical graphene with three-dimensional porous array structure/titanium niobium oxygen/sulphur carbon composite and its preparation method and application | |
| CN103531759B (en) | Two step absorption preparation methods of high magnification sulphur/middle microporous carbon HAC anode composite material of lithium sulfur battery | |
| CN103390752B (en) | Graphene-based matrix material, its preparation method and the application in lithium-sulfur cell thereof | |
| CN107919461A (en) | The preparation method of a kind of porous carbon cathode material of N doping and application | |
| CN107959005A (en) | A kind of composite material of transient metal sulfide and graphene and preparation method and application | |
| Chen et al. | Cobalt embedded in porous carbon fiber membranes for high-performance lithium-sulfur batteries | |
| CN108023062A (en) | A kind of lithium sulfur battery anode material | |
| CN107464938B (en) | Molybdenum carbide/carbon composite material with core-shell structure, preparation method thereof and application thereof in lithium air battery | |
| Liang et al. | Facilitation of lithium polysulfides adsorption by nitrogen doped carbon nanofibers with 3D interconnected pore structures for high-stable lithium-sulfur batteries | |
| CN109473643B (en) | CoSe2Preparation method and application of graphene composite material | |
| CN108258209A (en) | A kind of carbide/carbon nano tube/graphene carries sulphur composite material and preparation method and application | |
| CN105428618A (en) | Preparation method for shell-core type carbon-coated metal sulfide nano-composite particles and application of particles | |
| CN101521273B (en) | In-situ synthesis method for preparing tin-carbon/core-shell nano-particle fully filled carbon nano-tube composite anode material | |
| CN114388814B (en) | Preparation method of Co0.85Se nanoparticle@3D carbon network composite material and application of composite material in lithium-sulfur battery | |
| CN104779379A (en) | Novel sulfur and carbon composite material for lithium secondary battery, and preparation method thereof | |
| CN106554004A (en) | A kind of porous carbon materials prepared based on aromatic compound monomer and its production and use | |
| Zhang et al. | Shaddock wadding created activated carbon as high sulfur content encapsulator for lithium-sulfur batteries | |
| CN109671907A (en) | Lithium-sulfur cell anode composite piece, preparation method and application | |
| Cai et al. | Highly-ordered arrangement of Co (OH) F filaments: Planting flower-like Co (OH) F in conductive membrane substrate accelerating Li+ transfer and redox reaction in Li–S batteries | |
| CN106328895B (en) | A kind of graphene coated silkworm excrement multi-stage porous charcoal sulphur composite positive pole and preparation method | |
| CN106299287B (en) | A kind of carbonization silkworm excrement/MILs composite sulfur positive electrodes and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |