KR20180008986A - Preparation method of carbon material using microalgae - Google Patents

Abstract

The present invention provides a method of producing a carbon material, which comprises the steps of: (step 1) removing at least a part of lipids from microalgae; (step 2) mixing the microalgae from which lipids have been removed in step 1 with an inorganic compound to conduct a synthesis reaction to produce an inorganic-microalgae complex; and (step 3) thermally treating the inorganic-microalgae complex produced in step 2 to produce an inorganic-carbon complex. The method of producing a carbon material according to the present invention can produce a carbon complex having spheres of a uniform size. Further, since hydroxyl groups (-OH) and amide groups (-N) are increased due to removing or extracting lipids from microalgae, inorganic materials such as metal can be coated more efficiently and uniformly. Furthermore, microalgae are an excellent carbon precursor material, and contain nitrogen and phosphorus, and thus can be used to produce a carbon material having desirable electrochemical properties.

Description

Preparation method of carbon material using microalgae [

The present invention relates to a method for producing carbon materials using microalgae, and more particularly, to a method for producing carbon materials using microalgae and an application of the carbon materials.

At present, the depletion of energy resources and environmental pollution are emerging in the world, and secondary batteries are emerging as one way of coping with them. Although secondary batteries are widely applied to small-sized devices such as notebooks and mobile phones, they are very interested in application of secondary batteries to electric power storage systems such as hybrid electric vehicles (HEVs). Among the lithium secondary batteries of the future, mid- to large-sized batteries are particularly expected. In addition to HEVs, which have been commercialized in some commercial areas, they are capable of storing electricity generated by PHEV (PHEV), EV (Electric Vehicle) battery, robot battery or alternative energy such as solar, wind, Lithium secondary batteries are an important energy storage system and are recognized as a key element in next-generation smart grid technology. Secondary batteries which can be applied to hybrid vehicles or electric power storage systems must have a high charging / discharging speed and large secondary batteries. Of course, price, capacity and safety are essential.

Particularly, the demand for a lithium secondary battery (or a lithium ion battery) is greatly increased, and a high capacity and long life negative electrode capable of replacing a negative electrode material of a conventional commercial lithium secondary battery are actively under development. When the capacity of the negative electrode material is increased, the energy density of the lithium secondary battery can also be improved.

BACKGROUND ART [0002] Carbon-based materials are widely used as cathode materials for lithium secondary batteries. The carbonaceous anode active material can structurally reversibly insert and desorb lithium ions between carbon layers. The carbonaceous anode active material has an advantage of high capacity and has a high potential when a carbon-based cathode is used because of its low oxidation-reduction potential.

On the other hand, biomass can be used as a precursor of carbon-based materials with various structure and composition characteristics. Particularly, microorganisms such as bacteria and microalgae are uniform in shape, size and composition, and as a result, the microorganisms can provide nano-sized or micro-sized layered and well-ordered carbon sources and templates .

The inventors of the present invention have been studying a method for producing a carbonaceous material using microalgae, and at least a part of the lipids of microalgae as a carbon source is removed, and then the lipid-removed microalgae and the inorganic compound are mixed to prepare a mixture Carbon composite material. The present inventors have found that the inorganic-carbon composite material is excellent in electrochemical performance, and completed the present invention.

Korean Patent Publication No. 10-2010-0014074

An object of the present invention is to provide a method of manufacturing a carbon material excellent in electrochemical performance.

It is still another object of the present invention to provide a method for manufacturing a negative electrode material for a lithium ion battery excellent in electrochemical performance.

In order to achieve the above object,

Removing at least part of the lipids of the microalgae (step 1);

Mixing the microalgae from which the lipid has been removed and the inorganic compound in the step 1 and synthesizing them to prepare an inorganic microalgae complex (step 2); And

And a step (step 3) of preparing an inorganic-carbon composite by heat-treating the inorganic micro-algae composite produced in step 2 (step 3).

In addition,

A carbon material produced by the above production method is provided.

Further,

A negative electrode material for a lithium ion battery comprising a carbonaceous material produced by the above production method is provided.

Further,

Removing the lipids of the microalgae (step 1);

Preparing a negative electrode active material-microalgae composite by mixing the microalgae from which lipid has been removed and the negative electrode active material in step 1; And

And a step (step 3) of preparing the negative electrode active material-carbon composite by heat treating the negative electrode active material-microalgae composite prepared in the step 2 (step 3).

Further,

An anode including a cathode material manufactured by the above manufacturing method;

A cathode comprising a cathode active material; And

A lithium ion battery comprising: an electrolyte;

The carbon material manufacturing method according to the present invention can produce a carbon composite having a spherical shape of a uniform size. In addition, since the lipid (-OH) and amide groups (-N) are increased due to the lipid removal or extraction of the microalgae, the effect is more efficiently and homogeneously coated with an inorganic substance such as a metal. Furthermore, the microalgae contain nitrogen and phosphorus as excellent carbon precursor materials, so that carbon materials having excellent electrochemical performance can be produced.

1 is a photograph of a microalgae and lipid-removed microalgae observed with a scanning electron microscope (SEM) and a transmission electron microscope (TEM);
FIG. 2 is a graph showing an analysis of microalgae and lipid-removed microalgae by infrared spectroscopy (FT-IR);
FIG. 3 is a photograph of a carbon material produced in Example 1 by a transmission electron microscope (TEM); FIG.
4 is a photograph of a carbon material produced in Comparative Example 1 observed by a transmission electron microscope (TEM);
5 is a table in which the carbon material prepared in Example 1 and Comparative Example 1 was analyzed by X-ray photoelectron spectroscopy (XPS).

The present invention

Removing at least part of the lipids of the microalgae (step 1);

Mixing the microalgae from which the lipid has been removed and the inorganic compound in the step 1 and synthesizing them to prepare an inorganic microalgae complex (step 2); And

And a step (step 3) of preparing an inorganic-carbon composite by heat-treating the inorganic micro-algae composite produced in step 2 (step 3).

Hereinafter, the method for producing the carbon material according to the present invention will be described in detail for each step.

First, in the method for producing a carbonaceous material according to the present invention, step 1 is a step of removing at least a part of the lipids of the microalgae.

Step 1 is a step for preparing microalgae from which lipid has been removed. After preparation of microalgae, at least a part or all of the lipid present in the microalgae can be removed.

Specifically, the microalgae of step 1 may be algae, cyanobacteria, cryptobales, golden algae, euglena algae, diatoms, brown algae, red algae, green algae and axle algae. The microalgae can be used alone as a carbon source, and already contain hetero elements suitable for the activity of the oxygen reduction reaction.

At this time, in the present invention, it is possible to increase the hydroxyl group (-OH) and the amide group (-N) by removing the lipid of the microalgae, and thereby, more efficiently and homogeneously in the mixing and heat- Can be coated.

In addition, the lipid removal in step 1 may be performed by various methods that can remove or extract lipid from microalgae. However, as a specific example, the lipid of microalgae may be extracted with an organic solvent 1-1). ≪ / RTI >

The organic solvent in step 1-1 may be chloroform, methanol, dimethylformamide (DMF), or acetone. However, the organic solvent is not limited thereto, Any organic solvent capable of extracting algae lipids can be used without limitation.

In addition, the extraction in step 1-1 may be performed at a rotation speed of 300 rpm to 4,000 rpm after adding microalgae to the organic solvent, and may be performed at a rotation speed of 500 rpm to 3,000 rpm, To 2,000 rpm. Further, the stirring may be performed for 10 minutes to 24 hours, and may be performed for 30 minutes to 12 hours, and may be performed for 60 minutes to 6 hours.

Further, the method may further include a step (step 1-2) of filtering and drying the lipid-removed microalgae after performing step 1 above. The lipid-removed microalgae may be present as an organic solvent by performing the step 1 above. Therefore, after performing the step 1, filtration and drying may be performed to obtain only microalgae from which lipid has been removed. The filtration and drying process is performed by filtration using a centrifugal separator, a filter, etc., followed by lyophilization .

In addition, the lipid removed in step 1 above may be used for biodiesel synthesis. The lipid of the microalgae can form a fatty acid methyl ester (FAME), which is produced by reacting with short-chain alcohol (methanol, ethanol, propanol, butanol, etc.) under acid or base catalyst.

Next, in the method for producing a carbonaceous material according to the present invention, Step 2 is a step of preparing inorganic-microalgae complex by mixing lipid-removed microalgae and an inorganic compound in the step 1 and then synthesizing them.

In step 2, inorganic compounds are mixed to prepare inorganic-microalgae complex by mixing with lipid-removed microalgae.

Specifically, the inorganic compound of step 2 is preferably an inorganic compound capable of forming an inorganic material that can be used in various application fields by being combined with a carbon material. As a specific example, the carbon material produced by the above- When it is applied as an electrode material for a battery, it is preferably a metal compound including a metal used as an electrode active material, and when used as a catalyst, it is preferably a compound containing a catalytically active metal. More specifically, Sn, Si, Mg, Ca, Al, Ge, Pb, As, Sb, Bi, Pt, Ag, Au, Cd, Co, Cu, Fe, Mn, , Zn, and the like.

In addition, the mixing in step 2 may be performed using a solvent, and preferably, mixed using distilled water.

Further, when the mixing of step 2 is carried out using distilled water, the concentration of the lipid-removed microalgae may be 10 g / L to 1,000 g / L, and may be 50 g / L to 500 g / L And can be from 80 g / L to 200 g / L.

In addition, the concentration of the inorganic compound to be mixed in step 2 is preferably 0.01 M to 0.5 M, more preferably 0.02 M to 0.2 M, most preferably 0.03 M to 0.1 M. If the concentration of the inorganic compound to be added in the step 2 is less than 0.01 M, there is a problem that the inorganic compound to be added is insufficient and it is difficult to exert its performance as the inorganic-carbon composite in the future. If it exceeds 0.5 M, There is a problem that an impurity which is formed by clumping with only the inorganic compound is generated.

Further, the synthesis of step 2 is hydrothermal synthesis and may be carried out at a temperature of 100 ° C to 300 ° C for 6 hours to 60 hours, at a temperature of 150 ° C to 250 ° C for 12 hours to 48 hours, And at a temperature of 175 [deg.] C to 225 [deg.] C for 18 to 36 hours.

Further, after the synthesis of step 2, a filtration and drying step (step 2-1) may be further performed in order to recover the resulting inorganic micro-algae complex. In the step 2, the complex including the inorganic material and the microalgae synthesized by the hydrothermal synthesis according to the synthesis method may exist together with the distilled water. Therefore, after performing the step 2, the filtration and drying process may be performed to obtain only the inorganic micro-algae complex. The filtration and drying process may be performed using a centrifugal separator, a filter, Lt; 0 > C, preferably 100 < 0 > C to 120 < 0 > C.

Next, in the method for producing a carbon material according to the present invention, step 3 is a step of preparing an inorganic-carbon composite by heat-treating the inorganic micro-algae composite produced in step 2 above.

In step 3, the composite produced in step 2 is carbonized by heat treatment to produce an inorganic-carbon composite containing an inorganic material and carbon.

Specifically, the heat treatment in step 3 may be performed at a temperature of 450 ° C to 1,000 ° C. In addition, the heat treatment in step 3 may be performed under argon, nitrogen, or argon or nitrogen gas conditions containing hydrogen within 5%.

As a specific example, it is preferable that the heat treatment in the step 3 is performed by a first heat treatment at a temperature of 450 ° C to 600 ° C, and then a second heat treatment at a temperature of 650 ° C to 1,000 ° C. The first heat treatment may be performed for 30 minutes to 2 hours, and the second heat treatment may be performed for 30 minutes to 2 hours.

As described above, in the method for producing a carbonaceous material according to the present invention, the hydroxyl group (-OH) and the amide group (-N) are increased due to lipid removal or extraction of microalgae, There is an effect of coating.

In addition, a carbon composite having a spherical shape of a uniform size can be produced. The microalgae contain nitrogen and phosphorus as excellent carbon precursor materials and can be used as a carbon material having excellent electrochemical performance.

Further,

Preparing inorganic-microalgae complexes by mixing microalgae from which lipids have been removed and inorganic compounds (Step 1); And

The carbon material may be manufactured through the step of preparing the inorganic-carbon composite by heat-treating the inorganic micro-algae composite prepared in the step 2 (step 2).

Specifically, microalgae from which lipids are removed from the biodiesel production process can be prepared and used as a raw material for manufacturing the carbon material.

As described above, when micro-algae from which lipid is removed from the biodiesel production process is used, the problem of increasing the amount of micro-algae waste extracted from the biomass is eliminated, And can be recycled as a manufacturing method.

Further,

A carbon material produced by the above production method is provided.

The carbonaceous material according to the present invention is a carbonaceous material produced using lipid-free microalgae, which contains inorganic substances and carbon, and has a spherical shape of a uniform size.

Specifically, the size of the carbon material may be 0.1 탆 to 10 탆, may be 0.5 탆 to 5 탆, and may be 1 탆 to 4 탆.

In addition, since the lipid (-OH) and amide groups (-N) are increased due to lipid removal or extraction of microalgae, inorganic substances such as metals are coated more efficiently and homogeneously, Carbon material.

Furthermore, the carbon material may be used for an electrode of a secondary battery, an electrode of a fuel cell, a supercapacitor, a sensor, a catalyst, a water decomposition catalyst, and a hydrogen storage material.

Further,

A negative electrode material for a lithium ion battery comprising a carbonaceous material produced by the above production method is provided.

Further,

Removing at least part of the lipids of the microalgae (step 1);

Preparing a negative electrode active material-microalgae composite by mixing the microalgae from which lipid has been removed and the negative electrode active material in step 1; And

And a step (step 3) of preparing the negative electrode active material-carbon composite by heat treating the negative electrode active material-microalgae composite prepared in the step 2 (step 3).

Hereinafter, a method of manufacturing a cathode material for a lithium ion battery according to the present invention will be described in detail for each step.

First, in the method for manufacturing a lithium ion battery negative electrode material according to the present invention, step 1 is a step of removing at least a part of the lipid of the microalgae.

Step 1 is a step for preparing microalgae from which lipid has been removed. After preparation of microalgae, at least a part or all of the lipid present in the microalgae can be removed.

Specifically, the microalgae of step 1 may be algae, cyanobacteria, cryptobales, golden algae, euglena algae, diatoms, brown algae, red algae, green algae and axle algae. The microalgae can be used alone as a carbon source, and already contain hetero elements suitable for the activity of the oxygen reduction reaction.

At this time, in the present invention, it is possible to increase the hydroxyl group (-OH) and the amide group (-N) by removing the lipid of the microalgae, and thereby, more efficiently and homogeneously in the mixing and heat- Can be coated.

In addition, the lipid removal in step 1 may be performed by various methods that can remove or extract lipid from microalgae. However, as a specific example, the lipid of microalgae may be extracted with an organic solvent 1-1). ≪ / RTI >

The organic solvent in step 1-1 may be chloroform, methanol, dimethylformamide (DMF), or acetone. However, the organic solvent is not limited thereto, Any organic solvent capable of extracting algae lipids can be used without limitation.

In addition, the extraction in step 1-1 may be performed at a rotation speed of 300 rpm to 4,000 rpm after adding microalgae to the organic solvent, and may be performed at a rotation speed of 500 rpm to 3,000 rpm, To 2,000 rpm. Further, the stirring may be performed for 10 minutes to 24 hours, and may be performed for 30 minutes to 12 hours, and may be performed for 60 minutes to 6 hours.

Further, the method may further include a step (step 1-2) of filtering and drying the lipid-removed microalgae after performing step 1 above. The lipid-removed microalgae may be present as an organic solvent by performing the step 1 above. Therefore, after performing the step 1, filtration and drying may be performed to obtain only microalgae from which lipid has been removed. The filtration and drying process is performed by filtration using a centrifugal separator, a filter, etc., followed by lyophilization .

In addition, the lipid removed in step 1 above may be used for biodiesel synthesis. The lipid of the microalgae can form a fatty acid methyl ester (FAME), which is produced by reacting with short-chain alcohol (methanol, ethanol, propanol, butanol, etc.) under acid or base catalyst.

Next, in the method for manufacturing a lithium ion battery negative electrode material according to the present invention, Step 2 is a step of mixing the microalgae from which lipid has been removed and the negative electrode active material in Step 1, and then synthesizing the negative active material- microalgae composite .

In step 2, the negative active material is mixed and synthesized to prepare a negative active material-microalgae complex by mixing with lipid-removed microalgae.

The negative active material of step 2 is preferably a metal compound containing a metal and more specifically Sn, Si, Mg, Ca, Al, Ge, Pb, As, Sb, Bi, Pt, Ag, Or a salt containing elements such as Au, Cd, Co, Cu, Fe, Mn, Mo, Ti, Ni, V, W and Zn.

In addition, the mixing in step 2 may be performed using a solvent, and preferably, mixed using distilled water.

Further, when the mixing of step 2 is carried out using distilled water, the concentration of the lipid-removed microalgae may be 10 g / L to 1,000 g / L, and may be 50 g / L to 500 g / L And can be from 80 g / L to 200 g / L.

In addition, the concentration of the negative electrode active material mixed in step 2 is preferably 0.01 M to 0.5 M, more preferably 0.02 M to 0.2 M, most preferably 0.03 M to 0.1 M. When the concentration of the negative electrode active material added in the step 2 is less than 0.01 M, the negative active material to be added is insufficient, so that it is difficult to exert its performance as a negative electrode active material-carbon composite material in the future. When the concentration exceeds 0.5 M, There is a problem that an impurity which is formed by the aggregation of only the negative electrode active material occurs.

Further, the synthesis of step 2 is hydrothermal synthesis and may be carried out at a temperature of 100 ° C to 300 ° C for 6 hours to 60 hours, at a temperature of 150 ° C to 250 ° C for 12 hours to 48 hours, And at a temperature of 175 [deg.] C to 225 [deg.] C for 18 to 36 hours.

Further, after the synthesis of Step 2, a filtration and drying step (Step 2-1) may be further performed in order to recover the resulting negative electrode active material-microalgae complex. The composite comprising the synthesized negative electrode active material and the microalgae obtained by performing the hydrothermal synthesis according to the synthesis method in the step 2 may exist together with distilled water. Therefore, after performing the above step 2, the filtration and drying process may be performed to obtain only the negative electrode active material-microalgae complex. The filtration and drying process may be performed by filtration using a centrifugal separator, a filter, Lt; 0 > C to 150 < 0 > C, preferably 100 < 0 > C to 120 < 0 > C.

Next, in the method of manufacturing a lithium ion battery negative electrode material according to the present invention, step 3 is a step of preparing the negative electrode active material-carbon composite by heat treating the negative electrode active material-microalgae composite prepared in step 2 above.

In step 3, the composite prepared in step 2 is carbonized by heat treatment to produce a negative electrode active material-carbon composite including the negative active material and carbon.

Specifically, the heat treatment in step 3 may be performed at a temperature of 450 ° C to 1,000 ° C.

As a specific example, it is preferable that the heat treatment in the step 3 is performed by a first heat treatment at a temperature of 450 ° C to 600 ° C, and then a second heat treatment at a temperature of 650 ° C to 1,000 ° C. The first heat treatment may be performed for 30 minutes to 2 hours, and the second heat treatment may be performed for 30 minutes to 2 hours.

As described above, the production method of a lithium ion battery negative electrode material according to the present invention increases the hydroxyl group (-OH) and the amide group (-N) due to lipid removal or extraction of microalgae, There is an effect that the active material is coated.

In addition, a carbon composite having a spherical shape of a uniform size can be produced. The microalgae contain nitrogen and phosphorus as excellent carbon precursor materials and can be used as a carbon material having excellent electrochemical performance.

Further,

An anode including a cathode material manufactured by the above manufacturing method;

A cathode comprising a cathode active material; And

A lithium ion battery comprising: an electrolyte;

The lithium ion battery according to the present invention is excellent in electrochemical performance because it contains a carbon composite material prepared using lipid-free microalgae as a negative electrode, and thus is more uniformly coated with a negative electrode active material.

Hereinafter, examples and experimental examples of the present invention will be described in more detail.

However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the present invention is not limited by the following Examples and Experimental Examples.

≪ Example 1 > Production of carbon material

Step 1: Type of microalgae (microalgae) is 3.00 mM KNO ₃ as Chlorella sp.KR-1; KH ₂ PO ₄ 5.44 mM; Na ₂ HPO ₄ 1.83 mM; 0.20 mM MgSO ₄揃 7H ₂ O; CaCl ₂ 0.12 mM; 0.03 mM FeNaEDTA; 0.01 mM ZnSO ₄ .7H ₂ O; 0.07 mM MnCl ₂ .4H ₂ O; Al ₂ (SO ₄ ) ₃揃 18H ₂ O, 0.01 mM; And 0.07 mM CuSO ₄ in a medium containing carbon dioxide (CO ₂ ) at pH 6.5.

The cultured microalgae were mixed with an organic solvent mixed with chloroform (CHCl ₃ , 99%, Sigma Aldrich) and methanol at a volume ratio of 1: 1, and stirred vigorously at a rotation speed of 1,000 rpm for 2 The lipids were extracted by stirring for a period of time.

Thereafter, the solution was filtered and evaporated for 6 hours to obtain lipid-free microalgae, and the lipids in the filtered solution were recovered and used in the biodiesel manufacturing process. At this time, the microalgae from which lipids are extracted can be stored after lyophilization, and then used again.

Step 2: Tin chloride (tin (II) chloride anhydrous, SnCl ₂ , MW = 189.62, Junse, Japan) was added to distilled water at a concentration of 100 g / To prepare a mixed solution. The prepared mixed solution was hydrothermally synthesized overnight at a temperature of 195 ° C. Thereafter, the mixture was filtered using a nylon filter (0.2 μm, Whatman), and then dried at a temperature of 120 ° C. for 12 hours to prepare an inorganic micro-algae complex.

Step 3: The tin-carbon composite was prepared by carbonizing the inorganic micro-algae complex prepared in step 2 above. The carbonization was performed at a temperature of 500 ° C. for 1 hour and then at 800 ° C. for 1 hour in an argon gas atmosphere. At this time, the temperature was raised to 800 占 폚 at a rate of 10 占 폚 / min.

≪ Comparative Example 1 &

Step 1: Type of microalgae (microalgae) is 3.00 mM KNO ₃ as Chlorella sp.KR-1; KH ₂ PO ₄ 5.44 mM; Na ₂ HPO ₄ 1.83 mM; 0.20 mM MgSO ₄揃 7H ₂ O; CaCl ₂ 0.12 mM; 0.03 mM FeNaEDTA; 0.01 mM ZnSO ₄ .7H ₂ O; 0.07 mM MnCl ₂ .4H ₂ O; Al ₂ (SO ₄ ) ₃揃 18H ₂ O, 0.01 mM; And 0.07 mM CuSO _{4 in the} presence of carbon dioxide (CO ₂ ) at a pH of 6.5.

The mixed microalgae were added to distilled water at a concentration of 100 g / L and then 0.05 M of tin (II) chloride anhydrous, SnCl ₂ , MW = 189.62, Junse, Japan was added to prepare a mixed solution. The prepared mixed solution was hydrothermally synthesized overnight at a temperature of 195 ° C. Thereafter, the mixture was filtered using a nylon filter (0.2 μm, Whatman), and then dried at a temperature of 120 ° C. for 12 hours to prepare an inorganic micro-algae complex.

Step 2: The tin-carbon composite was prepared by carbonizing the inorganic-microalgae composite produced in the step 1 above. The carbonization was performed at a temperature of 500 ° C. for 1 hour and then at 800 ° C. for 1 hour in an argon gas atmosphere. At this time, the temperature was raised to 800 占 폚 at a rate of 10 占 폚 / min.

<Experimental Example 1> Morphology analysis

In order to confirm the morphology of the carbon material produced by the method of manufacturing carbon materials according to the present invention, the microalgae used in Example 1, microalgae from which lipid was removed after carrying out Step 1, The carbon material as the tin-carbon composite produced and the carbon material as the tin-carbon composite prepared in Comparative Example 1 were observed under a scanning electron microscope (SEM, HITACHI, S-4800), a transmission electron microscope (TEM, Tecnai, TF30 ST) Dispersive X-ray spectroscopy (EDS) and infrared spectroscopy (FT-IR). The results are shown in FIGS. 1 to 4.

As shown in Fig. 1, it can be confirmed that the microalgae have a spherical shape and show a size (or diameter) of 2 mu m to 3 mu m. Looking at the microalgae before removing lipids, starch granules and chloroplasts could be identified. If we look at the microalgae after removing the lipids, we can confirm that most of the lipids are removed.

In addition, as shown in FIG. 2, it was confirmed that hydroxyl groups (-OH) and amide functional groups (-N) were increased while lipid of microalgae was removed.

Further, as shown in FIG. 3, it can be confirmed that the tin-carbon composite produced in Example 1 has nanosized metal particles uniformly coated on the micro-sized carbon-based particles.

On the other hand, as shown in FIG. 4, the tin-carbon composites produced in Comparative Example 1 are not uniformly distributed, but a clustered portion appears.

Thus, when the specific surface area of the composites was examined by BET analysis, the specific surface area of Example 1 was 232.1 m ² / g, and the pore volume was very high (0.24 cm ³ / g) The specific surface area of Comparative Example 2 is 2.7 m ² / g, and the pore volume is 0.007 cm ³ / g, which is remarkably low.

X-ray photoelectron spectroscopy (XPS) analysis shows that N (nitrogen), P (phosphorus) and S (sulfur) are included in the tin-carbon composite. Such an external element is preferable because it can improve the electrochemical characteristics of the carbon material.

Claims (17)

Removing at least part of the lipids of the microalgae (step 1);
Mixing the microalgae from which the lipid has been removed and the inorganic compound in the step 1 and synthesizing them to prepare an inorganic microalgae complex (step 2); And
And heat-treating the inorganic micro-algae composite produced in step 2 to produce an inorganic-carbon composite (step 3).
The method according to claim 1,
Wherein the microalgae of step 1 is at least one selected from the group consisting of seaweeds, cyanobacteria, cryptobales, gold algae, euglena algae, diatoms, brown algae, red algae, green algae and axle algae.
The method according to claim 1,
Wherein the step 1 comprises extracting the lipids of the microalgae with an organic solvent (step 1-1).
The method of claim 3,
Wherein the organic solvent is at least one organic solvent selected from the group consisting of chloroform, methanol, dimethylformamide (DMF), and acetone.
The method of claim 3,
Wherein the extraction is carried out by adding the microalgae to the organic solvent and then stirring at a rotation speed of 300 rpm to 4,000 rpm for 10 minutes to 24 hours.
The method according to claim 1,
After performing step 1 above,
And filtering and drying the lipid-removed microalgae (step 1-2).
The method according to claim 1,
Wherein the concentration of the inorganic compound to be mixed in step 2 is 0.01 M to 0.5 M.
The method according to claim 1,
The inorganic compound of step 2 may be at least one selected from the group consisting of Sn, Si, Mg, Ca, Al, Ge, Pb, As, Sb, Bi, Pt, Ag, Au, Cd, Co, Cu, Fe, Mn, , W, and Zn. The method for producing a carbon material according to claim 1,
The method according to claim 1,
Wherein the synthesis of step 2 is hydrothermal synthesis and is carried out at a temperature of 100 ° C to 300 ° C for 6 hours to 60 hours.
The method according to claim 1,
The heat treatment in step 3 is carried out at a temperature of 450 ° C to 1,000 ° C in one kind of gas atmosphere selected from the group consisting of argon, nitrogen, argon containing not more than 5% of hydrogen and nitrogen containing not more than 5% Wherein the carbon material is a carbon material.
The method according to claim 1,
Wherein the heat treatment in step 3 is a first heat treatment at a temperature of 450 ° C to 600 ° C, and a second heat treatment at a temperature of 650 ° C to 1,000 ° C.
12. The method of claim 11,
Wherein the first heat treatment is performed for 30 minutes to 2 hours, and the second heat treatment is performed for 30 minutes to 2 hours.
A carbon material produced by the manufacturing method of claim 1.
14. The method of claim 13,
Wherein the carbon material has a size of 0.1 to 10 [mu] m.
A cathode material for a lithium ion battery comprising a carbon material produced by the manufacturing method of claim 1.
Removing at least part of the lipids of the microalgae (step 1);
Preparing a negative electrode active material-microalgae composite by mixing the microalgae from which lipid has been removed and the negative electrode active material in step 1; And
And a negative electrode active material-carbon composite by heat-treating the negative electrode active material-microalgae composite prepared in the step 2 (step 3).
An anode including a cathode material manufactured by the manufacturing method of claim 16;
A cathode comprising a cathode active material; And
A lithium ion battery comprising an electrolytic solution.

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