阅读说明：本技术 一种生物遗态结构SbC电池负极材料及其制备方法 (Biological morph-genetic structure SbC battery negative electrode material and preparation method thereof ) 是由 王庆 闫绳学 周萌 高成林 罗绍华 刘延国 张亚辉 王志远 郝爱民 于 2019-09-12 设计创作，主要内容包括：本发明涉及一种生物遗态结构SbC电池负极材料及其制备方法,通过对分心木进行酸液浸泡,得到保留了原材料结构的生物遗态碳,再通过对生物遗态碳复合方法制备出SbC复合材料,本发明具有以下有益效果：1、与碳复合提高了Sb的电子导电性；2、较大的孔道将会为K+的移动提供更为快速的扩散通道,而不同孔道之间所存在的胞状薄壁结构则可缩短K+在SbC复合材料内的传输距离,从而提高其离子导电性；3、众多的微小孔道也可让材料的比表面积得到提高,随着其比表面积的提高,其电池的比容量也会随之增加；4、通过KOH活化亦可控调节生物遗态碳中的孔道结构,从而可以进一步研究不同结构与性能之间存在的关系。(The invention relates to a SbC battery cathode material with a biological morph-genetic structure and a preparation method thereof, which comprises the steps of soaking diaphragma juglandis in acid liquor to obtain biological morph-genetic carbon with a retained raw material structure, and preparing a SbC composite material by a biological morph-genetic carbon composite method, wherein the invention has the following beneficial effects: 1. the electronic conductivity of Sb is improved by compounding with carbon; 2. the larger pore channels can provide a faster diffusion channel for the movement of K +, and the cellular thin-wall structure existing among different pore channels can shorten the transmission distance of K + in the SbC composite material, thereby improving the ionic conductivity of the composite material; 3. the specific surface area of the material can be improved by a plurality of micro-porous channels, and the specific capacity of the battery can be increased along with the improvement of the specific surface area; 4. the pore structure in the biological morph-genetic carbon can be controllably adjusted through KOH activation, so that the relation between different structures and performances can be further researched.)

1. A preparation method of a biological morph-genetic structure SbC battery negative electrode material is characterized by comprising the following steps:

s1, selecting a core wood and mechanically stripping;

s2, cleaning the surface of the split core wood mechanically stripped in the step S1 with deionized water to remove impurities;

s3, putting the diaphragma juglandis processed in the step S2 into a drying oven for drying for 24 hours, and selecting a certain mass of dried diaphragma juglandis to be soaked in a hydrochloric acid solution with a certain concentration for 24 hours after drying;

s4, adding the diaphragma juglandis subjected to soaking in the step S3 and KOH into a cylindrical nickel boat according to a certain mass ratio, adding a proper amount of deionized water until the diaphragma juglandis completely soaked for 24 hours, covering with a preservative film and pricking;

s5, pouring out the KOH solution in the nickel boat, putting the nickel boat in a drying box at 60 ℃, and drying the air components for 48 hours;

s6, after being fully dried, the diaphragma juglandis is put into a nickel boat and put into a tube furnace, a certain temperature rise gradient is set, and the diaphragma juglandis is fired in argon atmosphere;

s7, after the firing is finished, naturally cooling the material to be below 80 ℃, closing the tube furnace and the argon bottle, cooling for 12 hours, and taking out the material;

s8, grinding the material cooled in the step S7 by using a mortar and enabling the material to pass through a 300-mesh sieve to obtain biological morph-genetic carbon;

s9, introducing 1g of sodium hypophosphite, 0.5g of biological morphgenetic carbon, 0.20g of sodium hydroxide and antimony trichloride into a reaction kettle and dissolving in ethanol;

s10, the reaction kettle cover is stirred for 2 hours by using a film. Then the reaction kettle is put into a large kettle and placed in a homogeneous reactor, the temperature is set to be 180 ℃, the rotating speed is 11, and the hydrothermal treatment is carried out for 12 hours;

s11, opening the reaction kettle after the reaction kettle is fully cooled, taking out the mixed liquid, and carrying out solid-liquid separation by using a high-speed centrifuge;

s12, taking out the solid, adding a large amount of deionized water, performing suction filtration by using a suction filtration instrument, and washing off NaCl in the solid phase;

s13, taking out the cleaned solid phase, putting the solid phase into a glass culture dish, and putting the glass culture dish into a drying oven to dry for 12 hours at the temperature of 60 ℃;

s14, placing the pure Sb, the citric acid and the deionized water dried in the step S13 in a glass cup, placing the glass cup on a magnetic stirrer, stirring the glass cup for 30min, and then placing the glass cup in a drying oven to dry the glass cup for 48 h;

and S15, placing the dried solid mixture in a nickel boat and placing the nickel boat in a tube furnace, setting a certain temperature rise gradient, and firing the mixture in an argon atmosphere to obtain the biological morph-genetic structure SbC battery cathode material.

2. The method for preparing the negative electrode material of the biological morph-genetic structure SbC battery according to claim 1, wherein the method comprises the following steps: the mass of the diaphragma juglandis is 25g after the drying in the step S3 is finished.

3. The method for preparing the negative electrode material of the biological morph-genetic structure SbC battery according to claim 1, wherein the method comprises the following steps: the concentration of the hydrochloric acid in the step S3 is 1 mol/L.

4. The method for preparing the negative electrode material of the biological morph-genetic structure SbC battery according to claim 1, wherein the method comprises the following steps: in the step S4, the mass ratio of the central wood to the KOH is 1: 1.

5. the method for preparing the negative electrode material of the biological morph-genetic structure SbC battery according to claim 1, wherein the method comprises the following steps: the temperature rise gradient in the step S6 is 60min for 20-200 ℃, the temperature is slowly raised at 200-400 ℃ according to 2 ℃/min, 200min for 400-800 ℃, and the temperature is preserved for 120min at 800 ℃.

6. The method for preparing the negative electrode material of the biological morph-genetic structure SbC battery according to claim 1, wherein the method comprises the following steps: the temperature rise gradient in the step S15 is 60min at 20-200 ℃, 90min at 200-650 ℃, and then the temperature is kept for 4h at 650 ℃.

7. A biological morph-genetic structure SbC battery negative electrode material is characterized in that: the biological morph-genetic structure SbC battery negative electrode material is prepared by the preparation method of the biological morph-genetic structure SbC battery negative electrode material.

Technical Field

The invention belongs to the field of energy materials, and particularly relates to a SbC battery cathode material with a biological genetic structure and a preparation method thereof.

Background

At present, since researchers are still in the beginning stage of research on potassium ion batteries and mainly focus on the research on positive electrode materials, and the types of materials studied have many similar directions to Li + batteries, and the research on negative electrode materials of potassium ion batteries is also necessary, metal negative electrode materials are adopted herein: sb and a core wood (carbon source) are doped through hydrothermal treatment, so that the obtained composite carbon has high specific capacity of a metal material and stable cycle performance of a carbon-based negative electrode.

As described above, antimony is a K + battery alloy cathode with great potential, but with respect to the problems of low antimony ion and electronic conductivity, and easy occurrence of volume expansion, the existing research is actually to perform nanocrystallization treatment on Sb, for example, Sb is prepared into structures such as nanoscale rods and nanoscale tubes, so that the ion transmission path is shortened, the specific surface area of the material is increased, and the ion conductivity is further improved. Meanwhile, Sb and carbon are combined into a composite material, such as SbC composite material and the like, so that the electronic conductivity and the electronic acceptance of the active material are improved. However, there are many deficiencies in the research so far:

① nanometer Sb particles are easy to agglomerate, so the agglomeration problem is reduced by using a carbon-coated composite method, ② has great difficulty and uncertainty due to the complex process for constructing a special structure, and a simple method needs to be found to construct a structure suitable for K + migration so as to realize controllable adjustment.

The biological morphgenetic material has a structure with multi-level distribution, the pore size distribution of the biological morphgenetic material is from nano-scale to micron-scale and is not the same, and the pore size of the biological morphgenetic material can be further increased by a KOH activation mode. The special hierarchical porous structure of the core-division wood is exactly in line with the ideal structure of the battery electrode material, and because the core-division wood has a plurality of pore passages with different sizes, different pore passages can provide different effects for the battery, electrolyte can be buffered in larger pores, the pore passages can also be used as the passages for the rapid transmission of ions, and a plurality of micro-pore passages can provide larger specific surface area for the carbon source.

① is compounded with carbon to improve the electronic conductivity of Sb, larger pore channels provide faster diffusion channels for the movement of K +, cellular thin-wall structures among different pore channels can shorten the transmission distance of K + in SbC composite material to improve the ionic conductivity, the specific surface area of the material can be improved by a plurality of micro pore channels, the specific capacity of a battery can be increased along with the improvement of the specific surface area, and the pore channel structure in the biological morphotropic carbon can be controllably adjusted through KOH activation, so that the relation among different structures and performances can be further researched.

Disclosure of Invention

Aiming at the technical defects, the invention provides a SbC battery cathode material with a biological morph-genetic structure and a preparation method thereof, the invention adopts a biological morph-genetic material such as diaphragma juglandis, is natural, environment-friendly, cheap and easy to obtain, and adopts the following technical scheme.

In order to achieve the purpose, the invention provides the following technical scheme:

a preparation method of a biological morph-genetic structure SbC battery negative electrode material comprises the following steps:

s1, selecting a core wood and mechanically stripping;

s2, cleaning the surface of the split core wood mechanically stripped in the step S1 with deionized water to remove impurities;

s3, putting the diaphragma juglandis processed in the step S2 into a drying oven for drying for 24 hours, and selecting a certain mass of dried diaphragma juglandis to be soaked in a hydrochloric acid solution with a certain concentration for 24 hours after drying;

s4, adding the diaphragma juglandis subjected to soaking in the step S3 and KOH into a cylindrical nickel boat according to a certain mass ratio, adding a proper amount of deionized water until the diaphragma juglandis completely soaked for 24 hours, covering with a preservative film and pricking;

s5, pouring out the KOH solution in the nickel boat, putting the nickel boat in a drying box at 60 ℃, and drying the air components for 48 hours;

s6, after being fully dried, the diaphragma juglandis is put into a nickel boat and put into a tube furnace, a certain temperature rise gradient is set, and the diaphragma juglandis is fired in argon atmosphere;

s7, after the firing is finished, naturally cooling the material to be below 80 ℃, closing the tube furnace and the argon bottle, cooling for 12 hours, and taking out the material;

s8, grinding the material cooled in the step S7 by using a mortar and enabling the material to pass through a 300-mesh sieve to obtain biological morph-genetic carbon;

s9, introducing 1g of sodium hypophosphite, 0.5g of biological morphgenetic carbon, 0.20g of sodium hydroxide and antimony trichloride into a reaction kettle and dissolving in ethanol;

s10, the reaction kettle cover is stirred for 2 hours by using a film. Then the reaction kettle is put into a large kettle and placed in a homogeneous reactor, the temperature is set to be 180 ℃, the rotating speed is 11, and the hydrothermal treatment is carried out for 12 hours;

s11, opening the reaction kettle after the reaction kettle is fully cooled, taking out the mixed liquid, and carrying out solid-liquid separation by using a high-speed centrifuge;

s12, taking out the solid, adding a large amount of deionized water, performing suction filtration by using a suction filtration instrument, and washing off NaCl in the solid phase;

s13, taking out the cleaned solid phase, putting the solid phase into a glass culture dish, and putting the glass culture dish into a drying oven to dry for 12 hours at the temperature of 60 ℃;

s14, placing the pure Sb, the citric acid and the deionized water dried in the step S13 in a glass cup, placing the glass cup on a magnetic stirrer, stirring the glass cup for 30min, and then placing the glass cup in a drying oven to dry the glass cup for 48 h;

and S15, placing the dried solid mixture in a nickel boat and placing the nickel boat in a tube furnace, setting a certain temperature rise gradient, and firing the mixture in an argon atmosphere to obtain the biological morph-genetic structure SbC battery cathode material.

Preferably, the mass of the split core wood after the completion of the drying in the step S3 is 25 g.

Preferably, the concentration of hydrochloric acid in the step S3 is 1 mol/L.

Preferably, in step S4, the mass ratio of cedar to KOH is 1: 1.

preferably, the temperature rise gradient in the step S6 is 60min for 20-200 ℃, the temperature is slowly raised to 200-400 ℃ according to 2 ℃/min, 200min for 400-800 ℃, and the temperature is preserved for 120min at 800 ℃.

Preferably, the temperature rise gradient in the step S15 is 60min at 20-200 ℃, 90min at 200-650 ℃, and then the temperature is kept at 650 ℃ for 4 h.

Compared with the prior art, the invention has the following beneficial effects:

1. the electronic conductivity of Sb is improved by compounding with carbon;

2. the larger pore channels can provide a faster diffusion channel for the movement of K +, and the cellular thin-wall structure existing among different pore channels can shorten the transmission distance of K + in the SbC composite material, thereby improving the ionic conductivity of the composite material;

3. the specific surface area of the material can be improved by the plurality of micro-pores, and the specific capacity of the battery can be increased along with the improvement of the specific surface area;

4. the pore structure in the biological morph-genetic carbon can be controllably adjusted through KOH activation, so that the relation between different structures and performances can be further researched.

Drawings

FIGS. 1-4 are SEM, XRD, rate performance curves and impedance performance curves of electrode materials prepared by the direct compounding method.

FIGS. 5-8 are SEM, XRD, rate performance curves and impedance performance curves of electrode materials prepared by KOH activation recombination.

FIGS. 9-12 are SEM, XRD, rate performance curves and impedance performance curves of electrode materials prepared by carbon coating.

Detailed Description

The technical solutions in the embodiments of the present invention are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.