CN108807912B

CN108807912B - C @ SnOx(x=0,1,2)Preparation and application of @ C mesoporous nano hollow sphere structure

Info

Publication number: CN108807912B
Application number: CN201810609576.6A
Authority: CN
Inventors: 锁国权; 李丹; 杨艳玲; 王祎; 左玉; 侯小江; 冯雷; 王成威
Original assignee: Shaanxi University of Science and Technology
Current assignee: Shenzhen Wanzhida Technology Co ltd
Priority date: 2018-06-13
Filing date: 2018-06-13
Publication date: 2021-02-19
Anticipated expiration: 2038-06-13
Also published as: CN108807912A

Abstract

C @ SnO_x(x＝0,1,2)The preparation and application of the @ C mesoporous nano hollow sphere structure are characterized in that 3-aminophenol with certain mass is dissolved in deionized water to obtain a solution A; adding formaldehyde into the solution A to obtain a solution B; adding acetone into the solution B to obtain a solution or emulsion C to obtain a precursor nano hollow sphere; putting the precursor nano hollow sphere into deionized water to obtain a solution D; adding an organic substance to obtain a solution E; adding a certain mass of tin dichloride into the solution E to obtain a solution F; adding urea with certain mass into the solution F to obtain a solution G; transferring the solution G to a hydrothermal reaction kettle, carrying out hydrothermal reaction, cooling, centrifuging and drying to obtain a composite nano hollow sphere; carbonizing the obtained nano hollow sphere in a mixed gas of argon and hydrogen at a certain temperature to obtain C @ SnO_{x(x＝0，1，2)}The material used in the invention is cheap, and the preparation operation is simple.

Description

C @ SnOx(x=0,1,2)Preparation and application of @ C mesoporous nano hollow sphere structure

Technical Field

The invention relates to the technical field of power battery materials, in particular to C @ SnO_x(x＝0,1,2)Preparation and application of a @ C mesoporous nano hollow sphere structure.

Background

The problem of energy crisis and environmental pollution has always been an important issue affecting the sustainable development of economy. Therefore, the search for new energy becomes an urgent problem to be solved, and the secondary power battery enters the field of vision. In order to obtain high energy density, the metallic lithium positioned at the upper left of the periodic table becomes the first choice of the secondary battery at present, and the standard electrode potential (-3.04V) of the extreme negative of the metallic lithium means that the battery has high voltage output after the metallic lithium and the positive electrode form a full battery; lithium metal is the lightest metal, which in turn means a higher specific capacity. Energy is the specific capacity x voltage, so the lithium-related battery technology energy density is almost the highest among the current batteries. In addition, lithium ion batteries also have the advantage of being small in size. Therefore, the method rapidly promotes the revolutionary development of the fields such as smart phones, cameras, notebook computers and electric vehicles after the industrialization of the 90 s. However, the content of lithium only accounts for 0.017 percent of the total content of the crust, the lithium is insufficient with the increase of the used amount, the price of the lithium is higher and higher, and the contents of sodium and potassium in the same main group are respectively 2.09 percent and 2.36 percent, and the price is much lower than that of the lithium. In addition, lithium batteries appear to have encountered a "bottleneck" to date, have slow energy density increases, have slow cost reductions, and have encountered challenges in terms of fast charging, temperature range adaptation, larger scale deployment applications (electric vehicles, energy storage), and resource abundance. Therefore, people are always looking for a new secondary battery technology to make up for the defects of the lithium battery, and the potassium ion battery is paid attention to.

The research on the potassium ion battery is still in the early stage and is a hot spot of the research, and related reports are increased year by year. The radius of potassium ion (0.98) is larger than that of lithium ion (0.69), so that the potential barrier which needs to be overcome by potassium ion diffusion in the process of charging and discharging is larger, and the diffusion rate is greatly reduced. And the distance between graphite layers of the commercialized cathode material is too small, so that potassium ions are not suitably extracted, and therefore a suitable battery cathode potassium storage material needs to be found. Tin dioxide is an important lithium ion battery cathode material and has higher theoretical capacity (783Amh g)^-1) More than 2 times of the theoretical capacity of the commercial carbon cathode material, and has high conductivity (about 21.1 omega cm) and higher electron mobility (about 100-200 cm) compared with other oxide semiconductor materials²·V^-1·S^-1) But the volume expansion of the electrolyte can reach 3 times of the original volume expansion in the charging and discharging process, and the electrolyte is easy to be powdered or agglomerated, so that the circulation of the potassium ion battery is realizedThe performance is relatively poor. Therefore, the carbon coating is carried out on the surface of the porous carbon material, and the space provided by the carbon spheres is utilized to relieve SnO_{X(X＝0，1，2)}The volume expansion of the composite material improves the conductivity of the composite material, is beneficial to the rapid embedding and removing of potassium ions, improves the cycling stability of the battery and prolongs the service life of the battery. The method has great potential application value in the cathode material of the power potassium ion battery. Meanwhile, the material has the advantages of no toxicity, no pollution, high safety performance, wide raw materials and the like. Mesoporous nano hollow sphere structure SnO_{X(X＝0，1，2)}Has quantum size effect, large specific surface area, high surface activity and mesoporous nano hollow sphere structure SnO_{X(X＝0，1，2)}The material has a wide application prospect in various fields such as energy conversion and energy storage equipment, and therefore becomes a hot point of research.

C@SnO_{x(x＝0，1，2)}The @ C potassium ion battery negative electrode active material, the preparation method and related research work thereof are not reported at present.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention aims to provide C @ SnO_x(x＝0,1,2)The preparation and application of the @ C mesoporous nano hollow sphere structure are characterized in that a template solvothermal method is selected to prepare the mesoporous nano hollow sphere structure, and the reaction temperature and time are adjusted to obtain the cheap potassium ion battery cathode material.

In order to achieve the purpose, the invention adopts the technical scheme that:

c @ SnO_x(x＝0,1,2)The preparation method of the @ C mesoporous nano hollow sphere structure comprises the following steps:

1) dissolving a certain mass of 3-aminophenol in deionized water to obtain a solution A;

2) adding formaldehyde into the solution A under magnetic stirring to obtain a solution B;

3) adding acetone into the solution B under magnetic stirring to obtain a solution or emulsion C;

4) stirring the solution or the emulsion C for a certain time, centrifuging and drying at a certain temperature to obtain a precursor nano hollow sphere;

5) placing the precursor nano hollow ball in 30ml of deionized water, and carrying out ultrasonic treatment for a certain time to obtain a solution D;

6) adding an organic matter into the solution D under magnetic stirring to obtain a solution E;

7) adding tin dichloride with certain mass into the solution E under magnetic stirring to obtain a solution F;

8) under the magnetic stirring, adding urea with certain mass into the solution F to obtain solution G;

9) transferring the solution G to a hydrothermal reaction kettle for hydrothermal reaction, cooling after the reaction is finished, centrifuging and drying at a certain temperature to obtain a composite nano hollow sphere;

10) carbonizing the obtained nano hollow sphere in a mixed gas of argon and hydrogen at a certain temperature to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous nanometer hollow sphere of @ C.

In the step 2), the mass ratio of the 3-aminophenol to the formaldehyde is 1-10: 4-9.

In the step 3), the mass ratio of the 3-aminophenol to the acetone is 1-10: 3-16.

In the step 4), the stirring time is 6-24h, the rotation speed and the time of centrifugation are 8000 rpm/min-10000 rpm/min and 10min respectively, and the drying temperature is 60 ℃ and 8 h.

In the step 5), the ultrasonic treatment time is 10-60 min.

In the step 6), the organic substances are glucose, dopamine, sodium citrate, beta-cyclodextrin and the like, wherein the mass ratio of the 3-aminophenol to the organic substances is as follows: 1-10: 10-90.

In the step 7), the mass ratio of the 3-aminophenol to the tin dichloride is as follows: 1-10: 6.

In the step 8), the mass ratio of the 3-aminophenol to the urea is as follows: 1-10: 6.

In the step 9), the hydrothermal reaction conditions are 180-200 ℃ and 18-24 h; the centrifugation condition is 8000 rmp/min-10000 rmp/min, 10min, the drying condition is 60 ℃, 24 h.

In the step 10), the carbonization temperature is 450-650 ℃, and the ratio of argon to hydrogen is 1: 2-2: 1.

C@SnO_x(x＝0,1,2)The application of the @ C mesoporous nano hollow sphere structure in the preparation of a potassium ion battery comprises the following steps;

1) respectively weighing the following components in percentage by mass: 9-Y:1: Y (Y is more than or equal to 1 and less than or equal to 2) @ C SnO_{x(x＝0，1，2)}The preparation method comprises the steps of preparing polyvinylidene fluoride into a solution, adding the polyvinylidene fluoride into N-methyl pyrrolidone to prepare a solution with the mass fraction of 4%, stirring for 12 hours to obtain a light yellow liquid, namely preparing the polyvinylidene fluoride solution, and then mixing the polyvinylidene fluoride solution with carbon black and C @ SnO_{x(x＝0，1，2)}Mixing the @ C composite material in an agate mortar, grinding for 1-3 h, and then uniformly coating the mixture on a copper foil current collector; drying at 60 deg.C for 6h, cutting into 8mm round pieces with a mold, vacuum drying at 60 deg.C for 12h, and placing into a glove box to prepare for battery loading;

2) in a high-purity argon environment, metal potassium is used as a counter electrode, and an electrolyte is a 1M solution of Ethylene Carbonate (EC) and dicarboxylic acid carbonate (DMC) of potassium hexafluorophosphate (the volume ratio of EC to DMC is 1: 1) the polypropylene microporous membrane is a battery diaphragm and assembled into a button battery; and finally, testing the constant-current charge-discharge capacity and the cycle performance of the button cell.

The invention has the beneficial effects that:

the C @ SnO is prepared by the steps_{x(x＝0，1，2)}The @ C mesoporous nanosphere has the advantages of low-cost raw materials, simple preparation and convenient operation. The purity of the material is relatively high, the particle size of the mesoporous spheres is uniform, and the industrialization is easy to realize. Simultaneously, adding C @ SnO_{x(x＝0，1，2)}The @ C mesoporous nano hollow sphere as a negative electrode material of potassium ions shows excellent electrochemical performance, overcomes the problem of powdering caused by volume expansion of tin oxide during charging and discharging, has high specific capacity, and is favorable for developing potassium ion batteries.

The raw materials are cheap, the preparation operation is simple, the obtained material has high purity, the particle size of the mesoporous spheres is uniform, the mesoporous distribution is uniform, and the industrialization is easy to realize; the lithium iron phosphate anode material used as the anode material of the potassium ion battery shows excellent electrochemical performance.

Drawings

FIG. 1 is an SEM image of a precursor phenolic resin sphere of the present invention.

FIG. 2 is an SEM image of the present invention.

FIG. 3 is a charge-discharge cycle chart of the potassium ion battery negative electrode material of the present invention.

Detailed Description

The present invention will be described in further detail with reference to examples.

Example 1

C @ SnO_{x(x＝0，1，2)}The preparation method and the application of the @ C mesoporous nano hollow sphere structure comprise the following steps:

1) dissolving 0.01g of 3-aminophenol in 30mL of deionized water to obtain a solution A;

2) adding 0.05ml of formaldehyde into the solution A under magnetic stirring to obtain a solution B;

3) adding 5ml of acetone into the solution B under magnetic stirring to obtain a solution or emulsion C;

4) stirring the solution C for 6h at 8000rpm/min, centrifuging for 10min, and drying in a 60 ℃ oven for 8h to obtain precursor nanospheres;

5) putting the precursor nanospheres into 30ml of deionized water, and carrying out ultrasonic treatment for 60min to obtain a solution D;

6) adding 0.3g of glucose under magnetic stirring to obtain a solution E;

7) 0.564g of tin dichloride was added under magnetic stirring to give a solution F;

8) adding 0.6G of urea under magnetic stirring to obtain a solution G;

9) and transferring the solution G to a hydrothermal reaction kettle, and carrying out hydrothermal reaction for 18h at 180 ℃. Cooling after the reaction is finished, centrifuging at 8000rpm/min for 10min, and drying at 60 ℃ for 24h to obtain the composite hollow nanospheres;

10) and (3) enabling the obtained composite hollow nanospheres to have a flow rate ratio of argon to hydrogen at 450 ℃: carbonizing under the condition of 1:2 to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous hollow nanosphere of @ C.

Example 2

C @ SnO_{x(x＝0，1，2)}A preparation method and application of a @ C mesoporous hollow nanosphere structure comprise the following steps:

1) dissolving 0.05g of 3-aminophenol in 30mL of deionized water to obtain a solution A;

3) adding 10ml of acetone into the solution B under magnetic stirring to obtain a solution or emulsion C;

4) stirring the solution C for 6h at 8000rpm/min, centrifuging for 10min, and drying in an oven at 60 ℃ for 8h to obtain precursor hollow nanospheres;

5) putting the precursor hollow nanospheres into 30ml of deionized water, and carrying out ultrasonic treatment for 60min to obtain a solution D;

6) adding 0.6g of glucose under magnetic stirring to obtain a solution E;

8) adding 0.6G of urea under magnetic stirring to obtain a solution G;

10) and (3) enabling the obtained composite hollow nanospheres to have a flow rate ratio of argon to hydrogen of 500 ℃: carbonizing under the condition of 1:2 to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous hollow nanosphere of @ C.

Example 3

2) adding 0.1ml of formaldehyde into the solution A under magnetic stirring to obtain a solution B;

3) adding 15ml of acetone into the solution B under magnetic stirring to obtain a solution or emulsion C;

6) adding 0.6g of glucose under magnetic stirring to obtain a solution E;

8) adding 0.6G of urea under magnetic stirring to obtain a solution G;

10) and (3) enabling the obtained composite hollow nanospheres to have a flow rate ratio of argon to hydrogen at 550 ℃: carbonizing under the condition of 1:2 to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous hollow nanosphere of @ C.

Example 4

3) under the magnetic stirring, adding 20ml of acetone into the solution B to obtain a solution or emulsion C;

6) adding 0.9g of glucose under magnetic stirring to obtain a solution E;

8) adding 0.6G of urea under magnetic stirring to obtain a solution G;

10) and (3) enabling the obtained composite hollow nanospheres to have a flow rate ratio of argon to hydrogen at 600 ℃: carbonizing under the condition of 1:1 to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous hollow nanosphere of @ C.

Example 5

1) dissolving 0.1g of 3-aminophenol in 30mL of deionized water to obtain a solution A;

6) adding 0.9g of glucose under magnetic stirring to obtain a solution E;

8) adding 0.6G of urea under magnetic stirring to obtain a solution G;

10) and (3) enabling the obtained composite hollow nanospheres to have a flow rate ratio of argon to hydrogen at 650 ℃: carbonizing under the condition of 1:1 to obtain C @ SnO_{x(x＝0，1，2)}The mesoporous hollow nanosphere of @ C.

As shown in FIG. 1, the precursor was obtained by mixing 3-aminophenol and formaldehyde, stirring for 12 hours, centrifuging, and drying. The shape of the particles is a precursor of smooth carbon spheres with the surface, the radius of the spheres is about 400nm, and the spheres are uniform.

As shown in FIG. 2, the C @ SnO is obtained by adding tin chloride and glucose and then carbonizing at high temperature_{x(x＝0，1，2)}The mesoporous carbon ball of @ C has many small holes on the surface of the ball, and is formed by introducing hydrogen to etch the ball in the carbonization process. The holes etched on the surface of the sphere are uniform and consistent in size. The radius of the mesoporous sphere is about 500nm.

As shown in FIG. 3, is C @ SnO_{x(x＝0，1，2)}@ C constant current charge-discharge cycle curves at 1 st, 2 nd, 5 th, 10 th times with current density of 50mA/g and voltage of 0.01-2.6V. It is seen from fig. 3 that the first discharge capacity reaches 372.8mAh/g, the charge capacity is 121.1mAh/g, the coulombic efficiency is 32.48%, and the reason for the low first specific capacity may be that an SEI film is formed during charging and discharging, and part of potassium ions in the electrolyte are consumed. The coulombic efficiencies in the 2 nd, 5 th and 10 th times were 36.36%, 44.34% and 48.01%, respectively, and the coulombic efficiencies gradually increased, indicating that C @ SnO_{x(x＝0，1，2)}The @ C material has good cycle performance, and volume expansion of Sn and SnO2A in the charge-discharge process is relieved by carbon coating, so that the cycle life of the material is prolonged.

Claims

1. C @ SnO_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized by comprising the following steps of:

10) carbonizing the obtained nano hollow sphere in a mixed gas of argon and hydrogen at a certain temperature to obtain C @ SnO_xA mesoporous nano hollow sphere of @ C;

where x =0, 1, 2.

2. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 2), the mass ratio of 3-aminophenol to formaldehyde is 1-10: 4-9.

3. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 3), the mass ratio of 3-aminophenol to acetone is 1-10: 3-16.

4. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 4), the stirring time is 6-24 hours, the rotating speed and the time of centrifugation are 8000-10000 rpm/min and 10 minutes respectively, and the drying temperature is 60 ℃ and 8 hours.

5. A C @ SnO according to claim 1_xPreparation of @ C mesoporous nano hollow sphere structureThe method is characterized in that in the step 5), the ultrasonic treatment time is 10-60 min.

6. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 6), the organic matter is glucose, dopamine, sodium citrate or beta-cyclodextrin, wherein the mass ratio of the 3-aminophenol to the organic matter is as follows: 1-10: 10-90.

7. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 7), the mass ratio of 3-aminophenol to tin dichloride is as follows: 1-10: 6;

8. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 9), the hydrothermal reaction condition is 180-200 ℃ and 18-24 h; the centrifugation condition is 8000 rmp/min-10000 rmp/min, 10min, the drying condition is 60 ℃, 24 h.

9. A C @ SnO according to claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure is characterized in that in the step 10), the carbonization temperature is 450-650 ℃, and the ratio of argon to hydrogen is 1: 2-2: 1.

10. c @ SnO as set forth in claim 1_xThe preparation method of the @ C mesoporous nano hollow sphere structure applied to the potassium ion battery is characterized by comprising the following steps of;

1) respectively weighing the following components in percentage by mass: c @ SnO 9-Y:1: Y_x@ C composite material, carbon black and polyvinylidene fluoride, wherein polyvinylidene fluoride is prepared into solution, the polyvinylidene fluoride is added into N-methyl pyrrolidone to prepare solution with the mass fraction of 4%, and the solution is stirred for 12 percenth, preparing a polyvinylidene fluoride solution from the yellowish liquid, and then mixing the polyvinylidene fluoride solution with carbon black and C @ SnO_xMixing the @ C composite material in an agate mortar, grinding for 1-3 h, and then uniformly coating the mixture on a copper foil current collector; drying at 60 deg.C for 6h, cutting into 8mm round pieces with a mold, vacuum drying at 60 deg.C for 12h, and placing into a glove box to prepare for battery loading;

said x =0, 1, 2;

y is more than or equal to 1 and less than or equal to 2;

2) in the environment of high-purity argon, taking metal potassium as a counter electrode, taking an electrolyte as a solution of ethylene carbonate and dicarboxylic acid of 1M potassium hexafluorophosphate, taking a polypropylene microporous membrane as a battery diaphragm, and assembling into a button battery; and finally, testing the constant-current charge-discharge capacity and the cycle performance of the button cell.