Application of cation intercalation modified CuS @ CTAB electrode material in zinc ion battery
Technical Field
The invention belongs to the technical field of material synthesis and energy, and particularly relates to an application of a cation intercalation modified CuS @ CTAB electrode material in a zinc ion battery.
Background
Among them, lithium ion batteries have attracted attention due to their advantages of high operating voltage, high energy density, no memory effect, and environmental friendliness, and have become a research hotspot of great interest in the field of electrochemical energy conversion and storage, and are also considered to be the most promising power battery system for electric vehicles. However, it is undeniable that although the application range of the lithium ion battery is wider and wider, the organic electrolyte relied on by the lithium ion battery has serious safety hazards of toxicity and flammability. In recent years, lithium ion batteries have been subjected to safety accidents related to spontaneous combustion or explosion in smart phones, electric vehicles, and the like. With the development of the electric automobile industry, the primary factor to be considered in the operation process of the power battery in the electric automobile is how to ensure the safety of the battery. Therefore, safe and reliable aqueous zinc ion rechargeable batteries are receiving increasing attention.
Aqueous rechargeable batteries based on non-pyrophoric and high ionic conductivity aqueous electrolytes are safe and reliable electrochemical energy storage and conversion devices, and among numerous aqueous secondary batteries, zinc ion batteries are of particular interest. Because the zinc metal has higher theoretical specific capacity, such as the volume specific capacity of 5855mAh cm-3The specific mass capacity is 820mAh g-1Meanwhile, zinc metal has lower reduction potential (-0.76V) compared with a standard hydrogen electrode, and more importantly, zinc metal has low cost and abundant reserves and is very beneficial to the sustainable development in the future. However, zinc metal still faces a lot of serious problems in the aqueous electrolyte with mild chemical properties, such as corrosion of zinc metal and generation of hydrogen due to a series of side reactions of zinc metal in the aqueous electrolyte, and generation of uncontrollable zinc dendrite and thermal runaway and short circuit inside the battery due to long-term cyclic charge and discharge. Based on the challenges faced by the above-mentioned aqueous zinc-ion batteries, there have been many approaches aimed at suppressing or addressing to varying degrees a series of problems associated with zinc metal. Starting from electrolyte additives, e.g. polyacrylamide gel, nickel trifluoromethanesulfonate, ethylene glycol, benzyltrimethylammonium hydroxide, dodecyltrimethylammonium bromide, ethoxymethylAdditives such as ester, ether and the like can inhibit or delay side reactions of zinc metal and electrolyte from different layers, so that the growth of zinc dendrite is effectively inhibited; starting from the concentration of the electrolyte, the high-concentration electrolyte can reduce the corrosion degree of zinc metal caused by water due to low content of free water, and further reduce the risk of zinc dendrite growth, such as 20mol/L LiTFSI +1mol/L Zn (TFSI)2,30mol/L ZnCl2Etc., but this entails higher costs and an increase in the overall weight of the battery due to the larger amount of electrolyte required for the high concentration electrolyte. The interface modification angle of the contact between the zinc metal and the electrolyte is used, and the protective layer designed on the surface of the zinc metal can effectively reduce side reaction so as to improve the reversibility of the zinc metal, for example, a composite layer of polyamide and zinc trifluoromethanesulfonate is designed on the surface of the zinc metal, so that the direct contact between the zinc metal and the electrolyte can be isolated, and the uniform deposition of zinc ions can be regulated; coating materials such as organic metal frames, nano porous calcium carbonate, polyvinyl butyral, zinc oxide, zinc sulfide, carbon black, indium-based compounds and the like are designed on the surface of zinc metal and are proved to be capable of effectively delaying the growth of zinc dendrites, so that the electrochemical performance of the water system zinc ion battery is greatly improved.
Actually, besides zinc metal, an embedded type negative electrode and a conversion type negative electrode also exist in the water system zinc ion battery, wherein the dependence of the conversion type negative electrode on the crystal structure of an electrode material is low, high energy density can be released in the conversion process, and the zinc ion is generally embedded firstly in the conversion process, so that the direct deposition and stripping of the zinc ion on the surface of the electrode material are avoided, and the growth of zinc dendrite can be effectively inhibited, so that the conversion type negative electrode is beneficial to improving the energy density and the safety of the water system zinc ion battery, and has great research and practical values.
Disclosure of Invention
In order to overcome the defects in the prior artThe invention aims to provide an application of a cation intercalation modified CuS @ CTAB electrode material in a zinc ion battery; the preparation method of the CuS @ CTAB electrode material does not need solid-phase grinding, simplifies the preparation process, reduces the production cost, adopts a hydrothermal method to synthesize the material in one step, greatly shortens the reaction time, improves the product uniformity and avoids the generation of impurity phases; the CuS @ CTAB electrode material has increased interlayer spacing and a stable layer structure, and can stably perform repeated Zn2+The embedding and the further transformation process effectively avoid repeated Zn2+The formation of zinc dendrites due to deposition and exfoliation is an electrode material suitable for a zinc ion battery having high safety and a long life, and is useful for a zinc ion battery having high safety and a long life. .
The purpose of the invention is realized by the following technical scheme:
the application of the cation intercalation modified CuS @ CTAB electrode material in a zinc ion battery is characterized in that the zinc ion battery is a zinc ion secondary battery of water system electrolyte; the cation intercalation modified CuS @ CTAB electrode material is prepared according to the following preparation method: dissolving 1.8-2.0 mmol of copper nitrate trihydrate, 4-4.5 mmol of thiourea and 0.45-0.8 mmol of cetyltrimethylammonium bromide (CTAB) in a mixed solution of 28-30 mL of deionized water and 8-10 mL of ethylene glycol, carrying out hydrothermal reaction at 100-110 ℃ for 18-20 h, and carrying out cleaning and drying treatment to obtain the copper nitrate/ethylene glycol composite material.
The hydrothermal reaction is carried out in a 50-100 mL hydrothermal kettle; the cleaning is to wash away residual solution by deionized water and absolute ethyl alcohol; and the drying is carried out at 60-80 ℃ in vacuum.
The CuS @ CTAB electrode material can be used as a negative electrode material and assembled into a battery together with essential components such as a positive electrode, a diaphragm, an aqueous electrolyte and the like. Other components are not particularly limited as long as the negative electrode active material CuS @ CTAB and the corresponding negative electrode are provided, and the same components as those of a conventionally known aqueous electrolyte secondary battery can be used.
In the present invention, any positive electrode material generally used for zinc ion batteries can be used. As the positive electrode active material of the positive electrode, a compound capable of reversibly absorbing-releasing (intercalating and deintercalating) zinc ions can be used, and a metal oxide having stable properties is preferably used; porous materials with large specific surface area capable of reversibly adsorbing and desorbing anions can also be used, and activated porous carbon is preferably used.
For example, a conductive additive such as carbon black or acetylene black, or a binder such as polyvinylidene fluoride or polyethylene oxide is appropriately added to the above positive electrode active material to prepare a positive electrode material mixture, and the positive electrode material mixture is applied to a belt-shaped molded body having a current collecting material such as a steel mesh as a core material. However, the method for manufacturing the positive electrode is not limited to the above example.
In the aqueous electrolyte secondary battery of the present invention, the separator for separating the positive electrode from the negative electrode is not particularly limited, and various separators used in conventionally known aqueous electrolyte secondary batteries can be used. The diaphragm is used for separating the positive and negative active materials of the battery, so that any electron current between the positive and negative electrodes is prevented from directly passing through, and the short circuit of the battery is avoided; the resistance to flow of ions through the membrane is as low as possible, and porous polymeric membranes are most often used. For example, a fine porous separator formed of a polyolefin resin such as polyethylene or polypropylene, or a polyester resin such as polybutylene terephthalate is preferable. These fine porous separators (fine porous films) may be used in combination. The polymer microporous membrane is a film obtained by modifying the surface of the material, such as a composite ceramic diaphragm formed by coating ceramic powder (aluminum oxide, silicon oxide and the like) on polyolefin, can also be used. The thickness of the separator is not particularly limited, but is preferably 5 to 30mm in view of both safety and high capacity of the battery. The air permeability (s/100mL) of the separator is not particularly limited, but is preferably 10 to 1000(s/100mL), more preferably 50 to 800(s/100mL), and still more preferably 90 to 700(s/100 mL).
In the aqueous electrolyte secondary battery provided by the present invention, an aqueous solvent (deionized water) is used as the aqueous electrolyte solvent. As the electrolyte salt used in the aqueous electrolytic solution, zinc perchlorate, zinc sulfate, zinc salt of a fluorine-containing compound, zinc acetate and other zinc salts are preferable, and zinc sulfate hydrate is more preferable. The concentration of the zinc salt electrolyte in the aqueous electrolyte solution is preferably 0.3mol/L or more, more preferably 0.7 to 4mol/L, and still more preferably 3mol/L or less. When the concentration of the zinc salt in the electrolyte is too low, the ionic conductivity is too low, and when it is too high, there is a fear that the electrolyte salt cannot be dissolved completely and is precipitated.
In addition, various additives that can improve the performance of the battery using the aqueous electrolyte solution may be added to the aqueous electrolyte solution, and are not particularly limited. For example, an aqueous electrolyte solution containing polyacrylamide gel, nickel trifluoromethanesulfonate, ethylene glycol, benzyltrimethylammonium hydroxide, dodecyltrimethylammonium bromide, ethoxymethyl ester, or diethyl ether may be used to suppress a decrease in charge-discharge cycle characteristics of a battery using the aqueous electrolyte solution; the tendency of zinc dendrite growth may be suppressed by using a double electrolyte salt electrolyte solution containing a lithium salt, and among them, lithium bistrifluoromethanesulfonylimide (LiTFSI) is preferably used.
The method for producing an aqueous electrolyte secondary battery according to the present invention is, for example, a method in which the positive electrode and the negative electrode are stacked with the separator interposed therebetween to form an electrode laminate, the electrode laminate is wound to form an electrode wound body, the electrode wound body is packed in a package, the positive electrode and the negative electrode are connected to positive and negative electrode terminals of the package via lead members (lead tabs), the aqueous electrolyte is injected into the package, and the package is sealed.
As the package of the battery, a package of a square shape, a cylindrical shape, or the like made of a metal, a laminate package formed by laminating films of a metal (aluminum or the like), or the like can be used. The method for producing the aqueous electrolyte secondary battery and the structure of the battery are not particularly limited, and it is preferable to provide an opening formation step for charging after the positive electrode, the negative electrode, the separator and the aqueous electrolyte are provided in the package and before the battery is completely sealed. Gas generated at the initial stage of charging or water remaining in the battery can be removed to the outside of the battery. The method for removing the gas in the battery after the above-described opening chemical conversion step is not particularly limited, and any of natural removal and vacuum removal may be employed. Alternatively, the battery may be appropriately molded by pressing or the like before the battery is completely sealed.
The aqueous electrolyte secondary battery provided by the present invention has high capacity, high safety and good battery characteristics, and can be widely used not only as a secondary battery for a driving power source of portable information equipment such as a mobile phone and a notebook computer, but also as a power source of various devices such as an electric vehicle and a hybrid electric vehicle, by utilizing such characteristics.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the CuS @ CTAB electrode material disclosed by the invention is simple in preparation process, wide in raw material source and capable of being prepared in a large scale.
(2) The CuS @ CTAB electrode material prepared by the invention has increased interlayer spacing and can effectively promote Zn2+The intercalation and the further conversion process, and simultaneously, the existence of interlayer cations can stabilize the layer structure of CuS and effectively adsorb polysulfide in the reaction process, so that the electrochemical performance and the cycling stability of the CuS @ CTAB electrode material are obviously improved.
(3) The CuS @ CTAB electrode material prepared by the invention has higher specific capacity than pure CuS, and in a half-battery system assembled with zinc foil, 0.2A g-1Under the condition of (1), the pure CuS only has 20-50 mAh g-1The specific capacity of (1), and the CuS @ CTAB has a capacity of 300-380 mAh g-1The specific capacity of the copper-based alloy is obviously superior to that of pure CuS.
(4) The battery with the CuS @ CTAB electrode material prepared by the invention does not generate zinc dendrites on the surface of the negative electrode in the charge-discharge cycle process, and can prevent the internal short circuit phenomenon caused by the zinc dendrites; compared with the traditional lithium ion battery assembled by adopting the negative active material of low-potential metal lithium or graphite, the battery adopting the CuS @ CTAB electrode material is safer; according to the invention, a hydrothermal method is used for rapidly synthesizing the CuS @ CTAB electrode material in one step, the ball milling and tabletting operation steps of the traditional solid phase method are omitted, and the reaction time is greatly shortened.
Drawings
FIG. 1 is an XRD pattern of a CuS electrode material prepared in example 1;
FIG. 2 is an SEM photograph of a CuS electrode material prepared in example 1;
FIG. 3 is the electrochemical cycling performance of a CuS// Zn button half cell assembled with the CuS electrode material prepared in example 1;
FIG. 4 is an XRD pattern of the CuS @ CTAB electrode material prepared in example 2;
FIG. 5 is an SEM photograph of the CuS @ CTAB electrode material prepared in example 2;
FIG. 6 is the electrochemical cycling performance of a CuS @ CTAB// Zn button half cell assembled with the CuS @ CTAB electrode material prepared in example 2;
FIG. 7 is a graph of CuS @ CTAB// Zn assembled from the CuS @ CTAB electrode material prepared in example 2xMnO2Electrochemical cycling performance of the button full cell;
FIG. 8 is a graph of CuS @ CTAB// Zn assembled from the CuS @ CTAB electrode material prepared in example 2xCoFe(CN)6Electrochemical cycling performance of the button full cell;
FIG. 9 is the electrochemical cycling performance of a CuS @ CTAB// Zn button half cell assembled with the CuS @ CTAB electrode material prepared in example 3;
FIG. 10 is a graph of CuS @ CTAB// Zn assembled from the CuS @ CTAB electrode material prepared in example 3xMnO2Electrochemical cycling performance of the button full cell;
FIG. 11 is a graph of CuS @ CTAB// Zn assembled from the CuS @ CTAB electrode material prepared in example 3xCoFe(CN)6Electrochemical cycling performance of button full cell.
Detailed Description
The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto.
Example 1
1. Preparation: dissolving 1.8-2.0 mmol of copper nitrate trihydrate and 4-4.5 mmol of thiourea in 28-30 mL of mixed solution of deionized water and 8-10 mL of ethylene glycol, carrying out hydrothermal treatment at 100-110 ℃ for 18-20 h, washing off residual solution by using the deionized water and absolute ethyl alcohol, and then carrying out vacuum drying at 60-80 ℃ to obtain the CuS electrode material.
2. The performance of the CuS electrode material obtained in this example was characterized: the crystal structure of the material was analyzed by XRD diffractometer (using Rigaku MiniFlex600 diffractometer); the particle size and morphology of the material was analyzed by scanning electron microscopy (SU-8010, Hitachi). FIG. 1 is an XRD pattern of a CuS electrode material prepared in example 1; as can be seen from FIG. 1, the CuS has a diffraction signal peak of a layered structure at 10 to 12 degrees. Fig. 2 is an SEM photograph of the CuS electrode material prepared in example 1. As can be seen from FIG. 2, the surface morphology of the CuS electrode material is dense microspheres.
Application example 1
ZnSO in air4The battery is a 2032 button half-cell assembled by taking Whatman glass fiber as a diaphragm, a positive electrode active substance of the battery as a CuS electrode material, CuS as a positive electrode of the battery and Zn foil as a negative electrode of the battery, and the battery structure is CuS// Zn. Discharging and charging conditions: discharged to 0.3V at the same current density and then recharged to 0.9V, the current density being selected to be 0.2A g-1And testing the battery. Fig. 3 is the electrochemical cycling performance of a CuS// Zn button half cell assembled for the CuS electrode material prepared in example 1. As can be seen from FIG. 3, the obtained pure CuS has only 20-40 mAh g-1The specific capacity of (A).
Example 2
1. Preparation: dissolving 1.8-2.0 mmol of copper nitrate trihydrate, 4-4.5 mmol of thiourea and 0.45-0.8 mmol of hexadecyl trimethyl ammonium bromide (CTAB) in a mixed solution of 28-30 mL of deionized water and 8-10 mL of ethylene glycol, carrying out hydrothermal treatment for 18-20 h at 100-110 ℃, washing residual solution by using the deionized water and absolute ethyl alcohol, and then carrying out vacuum drying at 60-80 ℃ to obtain the cation intercalation modified CuS @ CTAB electrode material.
2. The cation intercalation modified CuS @ CTAB electrode material obtained in the embodiment is subjected to performance characterization: the crystal structure of the material was analyzed by XRD diffractometer (using Rigaku MiniFlex600 diffractometer); the particle size and morphology of the material was analyzed by scanning electron microscopy (SU-8010, Hitachi). FIG. 4 is an XRD pattern of the CuS @ CTAB electrode material prepared in this example 2; as can be seen from FIG. 4, the enhanced diffraction signal peak of the layered structure is found at 7-10 degrees in CuS @ CTAB. FIG. 5 is an SEM photograph of the CuS @ CTAB electrode material prepared in this example 2. As can be seen from fig. 5, the surface morphology of the CuS @ CTAB electrode material is flower-shaped microspheres formed by stacking nanosheets, the morphology has a form of an interconnected three-dimensional network structure, and the CuS @ CTAB electrode material can be used as an electrode material to increase the contact area of an electrode and an electrolyte and provide abundant porous tunnels for ion transport.
Application example 2
ZnSO in air4The electrolyte is adopted, Whatman glass fiber is used as a diaphragm, an active substance used by the positive electrode of the battery is the CuS @ CTAB electrode material prepared in the embodiment 2, the CuS @ CTAB is the positive electrode of the battery, a Zn foil is used as the negative electrode of the battery to assemble a 2032 button-type half-battery, and the battery structure is CuS @ CTAB// Zn. Discharging and charging conditions: discharged to 0.3V at the same current density and then recharged to 0.9V, the current density being selected to be 0.2A g-1And testing the battery. FIG. 6 is the electrochemical cycling performance of a CuS @ CTAB// Zn coin half cell assembled with the CuS @ CTAB electrode material prepared in example 2. As can be seen from FIG. 6, the obtained CuS @ CTAB has a g of 300-380 mAh-1The specific capacity of the copper-based alloy is obviously superior to that of CuS in application example 1.
Application example 3
The difference from application example 2 is that: the active material used by the battery anode is ZnxMnO2。
MnO of2Uniformly mixing the conductive carbon black and the binder according to the mass ratio of 7:2:1, adding a proper amount of N-methyl pyrrolidone to prepare slurry, and coating the slurry on a steel mesh to prepare the electrode. The test electrode was dried in a vacuum oven at 80 ℃ for 12h and air dried with ZnSO4As an electrolyte, MnSO4As electrolyte additive, Whatman glass fiber as diaphragm, Zn foil as negative electrode of battery, MnO2Assembling 2032 button type half cell for the positive electrode of the cell, wherein the cell structure is MnO2v/Zn and pre-insertion of Zn2+To obtain ZnxMnO2And (3) a positive electrode material.
ZnSO in air4As an electrolyte, MnSO4As electrolyte additive, Whatman glass fiber is used as a diaphragm, and the active substance used for the positive electrode of the battery is Zn obtained in the wayxMnO2The cathode material, CuS @ CTAB prepared in the embodiment 2 is used as the cathode of the battery to assemble a 2032 button type full battery, and the battery structure is CuS @ CTAB// ZnxMnO2. Discharging and charging conditions: to be provided withThe same current density was charged to 1.5V and discharged to 0.4V, with a current density of 2A g being selected-1And testing the battery. FIG. 7 is a graph of CuS @ CTAB// Zn assembled for the CuS @ CTAB electrode material prepared in example 2xMnO2Electrochemical cycling performance of button full cell. As can be seen from FIG. 7, the obtained CuS @ CTAB// ZnxMnO2Button type full cell is 2A g-1The specific capacity retention rate is up to more than 94.0 percent after 8000 cycles of charging and discharging under the current density.
Application example 4
The difference from application example 2 is that: the active material used for the positive electrode of the battery is ZnxCoFe(CN)6。
Mixing KCoFe (CN)6Uniformly mixing the conductive carbon black and the binder according to the mass ratio of 7:2:1, adding a proper amount of N-methyl pyrrolidone to prepare slurry, and coating the slurry on a steel mesh to prepare the electrode. The test electrode was dried in a vacuum oven at 80 ℃ for 12h in air with Zn (CF)3SO3)2Whatman glass fiber as a diaphragm, Zn foil as a battery cathode, KCoFe (CN) as an electrolyte6The positive electrode of the cell is assembled into a 2032 button type half cell, and the cell structure is KCoFe (CN)6v/Zn and pre-insertion of Zn2+To obtain ZnxCoFe(CN)6And (3) a positive electrode material.
Zn (CF) in air3SO3)2As electrolyte, Whatman glass fiber is used as a diaphragm, and the active material used by the positive electrode of the battery is ZnxCoFe(CN)6The cathode material, CuS @ CTAB prepared in the embodiment 2 is used as the cathode of the battery to assemble a 2032 button type full battery, and the battery structure is CuS @ CTAB// ZnxCoFe(CN)6. Discharging and charging conditions: charging to 1.8V at the same current density, and discharging to 0.6V at the current density of 2A g-1And testing the battery. FIG. 8 is a graph of CuS @ CTAB// Zn assembled for the CuS @ CTAB electrode material prepared in example 2xCoFe(CN)6Electrochemical cycling performance of button full cell. As can be seen from FIG. 8, the obtained CuS @ CTAB// ZnxCoFe(CN)6Button type full cell is 2A g-1Charging and discharging at current densityThe specific capacity retention rate after 6000 weeks of the ring is up to more than 76.1%.
Example 3
Preparation:
dissolving 1.8-2.0 mmol of copper nitrate trihydrate, 4-4.5 mmol of thiourea and 1.2-2.0 mmol of hexadecyl trimethyl ammonium bromide (CTAB) in a mixed solution of 28-30 mL of deionized water and 8-10 mL of ethylene glycol, carrying out hydrothermal treatment for 18-20 h at 100-110 ℃, washing residual solution by using the deionized water and absolute ethyl alcohol, and then carrying out vacuum drying at 60-80 ℃ to obtain CuS @ CTAB.
Application example 5
ZnSO in air4The electrolyte is a 2032 button half cell assembled by using Whatman glass fiber as a diaphragm, using an active substance used by a positive electrode of the cell as CuS @ CTAB obtained in example 3, using the CuS @ CTAB as the positive electrode of the cell and using Zn foil as the negative electrode of the cell, and the cell structure is CuS @ CTAB// Zn. Discharging and charging conditions: discharged to 0.3V at the same current density and then recharged to 0.9V, the current density being selected to be 0.2A g-1And testing the battery. FIG. 9 is the electrochemical cycling performance of a CuS @ CTAB// Zn coin half cell assembled with the CuS @ CTAB electrode material prepared in example 3. As can be seen from fig. 9, the obtained CuS @ CTAB has a significant specific capacity attenuation, which is significantly inferior to that of the application example 2.
Application example 6
The differences from application example 5 are: the active material used by the battery anode is ZnxMnO2。
MnO of2Uniformly mixing the conductive carbon black and the binder according to the mass ratio of 7:2:1, adding a proper amount of N-methyl pyrrolidone to prepare slurry, and coating the slurry on a steel mesh to prepare the electrode. The test electrode was dried in a vacuum oven at 80 ℃ for 12h and air dried with ZnSO4As an electrolyte, MnSO4As electrolyte additive, Whatman glass fiber as diaphragm, Zn foil as negative electrode of battery, MnO2Assembling 2032 button type half cell for the positive electrode of the cell, wherein the cell structure is MnO2v/Zn and pre-insertion of Zn2+To obtain ZnxMnO2And (3) a positive electrode material.
ZnSO in air4For electrolysis ofMaterial, MnSO4As electrolyte additive, Whatman glass fiber is used as a diaphragm, and the active substance used for the positive electrode of the battery is Zn obtained in the wayxMnO2The cathode material, CuS @ CTAB prepared in the example 3 is assembled into a 2032 button type full cell by taking the cathode of the cell as the cathode, and the cell structure is CuS @ CTAB// ZnxMnO2. Discharging and charging conditions: charging to 1.5V at the same current density, and discharging to 0.4V at the current density of 2A g-1And testing the battery. FIG. 10 is a graph of CuS @ CTAB// Zn assembled for the CuS @ CTAB electrode material prepared in example 3xMnO2Electrochemical cycling performance of button full cell. As can be seen from FIG. 10, the resulting CuS @ CTAB// ZnxMnO2Button type full cell is 2A g-1The specific capacity begins to obviously attenuate after 40 cycles of charging and discharging under the current density, and is obviously inferior to CuS @ CTAB// Zn in application example 3xMnO2Electrochemical cycling performance of button full cell.
Application example 7
The differences from application example 5 are: the active material used for the positive electrode of the battery is ZnxCoFe(CN)6。
Mixing KCoFe (CN)6Uniformly mixing the conductive carbon black and the binder according to the mass ratio of 7:2:1, adding a proper amount of N-methyl pyrrolidone to prepare slurry, and coating the slurry on a steel mesh to prepare the electrode. The test electrode was dried in a vacuum oven at 80 ℃ for 12h in air with Zn (CF)3SO3)2Whatman glass fiber as a diaphragm, Zn foil as a battery cathode, KCoFe (CN) as an electrolyte6The positive electrode of the cell is assembled into a 2032 button type half cell, and the cell structure is KCoFe (CN)6v/Zn and pre-insertion of Zn2+To obtain ZnxCoFe(CN)6And (3) a positive electrode material.
Zn (CF) in air3SO3)2Whatman glass fiber is used as a diaphragm as an electrolyte, and the active material used for the positive electrode of the battery is Zn obtained in the wayxCoFe(CN)6The cathode material, CuS @ CTAB prepared in the example 3 is assembled into a 2032 button type full cell by taking the cathode of the cell as the cathode, and the cell structure is CuS @ CTAB// ZnxCoFe(CN)6. Discharging and charging conditions: charging to 1.8V at the same current density, and discharging to 0.6V at the current density of 2A g-1And testing the battery. FIG. 11 is a graph of CuS @ CTAB// Zn assembled for the CuS @ CTAB electrode material prepared in example 3xCoFe(CN)6Electrochemical cycling performance of button full cell. As can be seen from FIG. 11, the resulting CuS @ CTAB// ZnxCoFe(CN)6Button type full cell is 2A g-1The specific capacity begins to obviously attenuate after 10 weeks of cycle of charging and discharging under the current density, and is obviously inferior to CuS @ CTAB// Zn in application example 4xCoFe(CN)6Electrochemical cycling performance of button full cell.
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 changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.