CN109052488B - A kind of cobalt disulfide material with high storage stability and preparation method and application thereof - Google Patents

Abstract

The invention relates to the technical field of electrode material preparation, in particular to a cobalt disulfide material with high storage stability and a preparation method and application thereof; the method comprises: configuring a cobalt disulfide replacement reactant; mixing the cobalt disulfide replacement reactant with Cobalt disulfide is mixed, placed at 120-600° C., and kept for reaction for 0.5-72 hours to prepare. In the present invention, a layer of protective layer structure is formed on the surface of cobalt disulfide by means of replacement under specific process conditions, which greatly improves the storage stability of cobalt disulfide, so that cobalt disulfide can be used as an electrode material in thermal batteries, lithium ion batteries, and lithium ion batteries. When used in batteries and other products, the performance of the battery has been greatly improved, and it has a huge application prospect.

Description

A kind of cobalt disulfide material with high storage stability and preparation method and application thereof

technical field

The invention relates to the technical field of electrode material preparation, in particular to a cobalt disulfide material with high storage stability and a preparation method and application thereof.

Background technique

As a sulfide with good electrical conductivity, CoS ₂ has excellent electrical, magnetic and catalytic properties, and has a wide range of applications in thermal batteries, lithium batteries, solar cells, supercapacitors and other fields. At present, the synthesis and preparation of CoS ₂ are mainly made by solid-phase method, which is made by high-temperature calcination of metallic cobalt and excess sulfur element, and sulfur removal process.

However, the CoS ₂ synthesized by the solid-phase method is easily decomposed during storage in an environment containing H ₂ O and O ₂ to generate CoSO ₄ ·H ₂ O, which significantly reduces its electrical and magnetic catalytic properties, and significantly affects its long-term stability. Its application is very limited.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a cobalt disulfide material with high storage stability and a preparation method thereof. The method solves the problem of easy decomposition by generating a layer of shell structure on the surface of the cobalt disulfide material and greatly improves the Its storage stability, the cobalt disulfide material with high storage stability is used as an electrode material in thermal batteries, lithium batteries, solar cells and supercapacitors, which greatly improves the performance of the above products and has broad application prospects.

The technical scheme that the present invention solves the above-mentioned technical problems is as follows: a preparation method of a cobalt disulfide material with high storage stability is provided, comprising:

(1) configure cobalt disulfide replacement reactant;

(2) The cobalt disulfide replacement reactant is mixed with cobalt disulfide, placed at 120-600 DEG C, and the reaction is kept for 0.5-72 hours to prepare.

The beneficial effects of adopting the above technical scheme are as follows: the present invention generates a layer of protective layer structure on the surface of the cobalt disulfide by means of replacement under specific process conditions, which greatly improves the storage stability of the cobalt disulfide and makes the cobalt disulfide When used as an electrode material in thermal batteries, lithium batteries and other products, the performance of the battery is greatly improved, and it has a huge application prospect.

Further, in step (1), the method for configuring cobalt disulfide replacement reactant comprises:

Using at least one of water and alcohol as a solvent, adding acid and metal salt to the above-mentioned solvent, stirring evenly, to obtain a cobalt disulfide precursor replacement solution; wherein, the solvent can be water or alcohol, or a mixture of water and alcohol , when it is a mixed solution of water and alcohol, the volume fraction of water is 50-90%, and the volume fraction of alcohol is 10-50%; the molar ratio of acid to metal salt is 0.5-3:1; metal salt is a soluble metal Salt.

The beneficial effect of adopting the above technical scheme is as follows: the cobalt disulfide precursor replacement solution of the present invention is composed of a certain proportion of water or alcohol or a solution of water and alcohol, thereby increasing the pressure of the reaction system, and promoting the replacement ion and cobalt disulfide to be uniform Coating can effectively promote the next displacement reaction.

Further, the concrete process of step (2) is:

The cobalt disulfide is placed in the cobalt disulfide precursor replacement solution to obtain a suspension, and then the above suspension is placed under the conditions of 120-240°C and 10-60Mpa, and the reaction is incubated for 24-48 hours, and then cooled. , to obtain a cobalt disulfide material with high storage stability; wherein, the concentration of cobalt disulfide is 20-100 g/L.

The beneficial effects of adopting the above technical scheme are: the present invention can effectively generate a layer of cobalt disulfide on the surface of the cobalt disulfide by performing the replacement reaction with the cobalt disulfide precursor replacement solution and cobalt disulfide in a certain ratio and under the conditions of temperature and pressure. A 3-30 nm thick shell layer avoids its direct contact with _H2O and _O2 , thereby improving the storage stability of _CoS2 .

Further, the cobalt disulfide was placed in the cobalt disulfide precursor replacement solution to obtain a suspension, and then the above suspension was placed under the conditions of 180 ° C and 10 Mpa, and the reaction was incubated for 48 hours, and then cooled to obtain a suspension with Cobalt disulfide material with high storage stability; wherein, the concentration of cobalt disulfide is 20-100g/L.

Further, the soluble metal salt is a soluble metal salt such as chloride, sulfate, oxalate, acetate, nitrate, cyanide of Fe, Ni, Mn, Zr or Ti; taking Fe as an example, it can be FeSO ₄ , FeCl ₂ , Fe(CN) ₂ , ferrous oxalate, etc.

The acid is at least one of hydrochloric acid, acetic acid, nitric acid, citric acid and sulfuric acid.

Further, in step (1), the method for configuring cobalt disulfide replacement reactant comprises:

Mix at least one of lithium halide, sodium halide and potassium halide to obtain a mixture, and then add a metal salt to the mixture and mix evenly to obtain cobalt disulfide replacement molten salt carrier; for example, lithium halide, sodium halide can be mixed Mixed with potassium halide, wherein the mass ratio of lithium halide in the mixture is 20-50%, the mass ratio of sodium halide in the mixture is 20-50%, and the mass ratio of potassium halide in the mixture is 30-60%;

The lithium halide includes at least one of LiF, LiCl and LiBr;

The sodium halide includes at least one of NaF, NaCl and NaBr;

The potassium halide includes at least one of KF, KCl and KBr;

Wherein, the component content of the lithium halide, sodium halide and potassium halide in the mixture is the lowest eutectic point component content of the mixture ± 5wt%; wherein, the lowest eutectic point component content is obtained through the database (website: http://www .crct.polymtl.ca/FACT/documentation/) to query.

The beneficial effect of adopting the above technical scheme is: the present invention provides a liquid environment by using the molten salt carrier of the halide as the replacement reactant, so as to promote the uniform coating of CoS by the replacement _ions , and can effectively promote the next step of the replacement reaction, In addition, the replacement layer is made uniform, so as to avoid insufficient replacement effect or performance degradation caused by too thin or too thick.

Further, the concrete process in step (2) is:

The cobalt disulfide replacement molten salt carrier is placed in a non-oxidizing atmosphere at 240-600 ° C, the reaction is kept for 0.5-12 hours, cooled, and a cobalt disulfide material with a shell structure is obtained by the reaction; wherein, cobalt disulfide and disulfide The mass ratio of the cobalt-substituted molten salt carrier is 1:1-5.

The cobalt disulfide material with high storage stability prepared by the above method has a protective layer on the surface of the material, which can avoid direct contact between CoS ₂ and H ₂ O and O ₂ during storage, thereby significantly improving the storage stability of CoS ₂ . , thereby avoiding the decline of electrical, magnetic and catalytic performance caused by the decomposition of CoS ₂ .

The above cobalt disulfide materials have high storage stability and are used in the preparation of thermal batteries, lithium batteries, solar cells and supercapacitor electrode materials, which greatly improves the thermal battery, lithium battery, solar energy using CoS ₂ as the electrode material. The performance of batteries and supercapacitors has broad application prospects and practical significance.

Description of drawings

1 is the XRD pattern of the cobalt disulfide material not treated by the method of the present invention and the cobalt disulfide material treated by the embodiment 1 of the present invention before and after being stored in air (100% humidity) for 170h respectively.

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings. The examples are only used to explain the present invention, but not to limit the scope of the present invention.

Example 1:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Configure cobalt disulfide precursor replacement solution: dissolve 0.05mol citric acid and 0.05mol FeCl ₂ into 100ml deionized water, stir evenly to obtain cobalt disulfide precursor replacement solution;

Add 0.05mol CoS to the above _- mentioned cobalt disulfide precursor replacement solution, stir evenly, and prepare a suspension;

The suspension was poured into the autoclave, and the reaction was kept at 200°C and 40Mpa for 24h;

The cooled mixture in the autoclave was washed-centrifuged and dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Example 2:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Prepare cobalt disulfide precursor replacement solution: Dissolve citric acid (0.2mol), sulfuric acid (0.01mol), and MnCl ₂ (0.1mol) into 100ml of a mixed solvent of ethylene glycol, glycerol, and butane erythritol, stir evenly, Obtain cobalt disulfide precursor replacement solution; wherein, the volume ratio of ethylene glycol, glycerol and butane erythritol is 2:1:1;

Add 0.1 mol CoS ₂ to the above-mentioned cobalt disulfide precursor replacement solution, stir evenly, and prepare a suspension;

The suspension was poured into the autoclave, and the reaction was kept at 180°C and 60Mpa for 30h;

The cooled mixture in the autoclave was washed-centrifuged and dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Example 3:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Prepare cobalt disulfide precursor replacement solution: dissolve citric acid (0.1mol), sulfuric acid (0.02mol), and Ni ₂ SO ₄ (0.1 mol) into 100 ml of a mixed solvent of ethylene glycol, glycerol, butylene erythritol and water , stir evenly to obtain a cobalt disulfide precursor replacement solution; the volume of ethylene glycol, glycerol, butane erythritol and water is 1:1:1:3;

Add 0.15mol CoS to the above _- mentioned cobalt disulfide precursor replacement solution, stir evenly, and prepare a suspension;

The suspension was poured into the autoclave, and the reaction was kept at 240°C and 10Mpa for 48h;

The cooled mixture in the autoclave was washed-centrifuged and dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Example 4:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Configure cobalt disulfide replacement molten salt carrier: mix 0.4g FeCl ₂ and 1g LiCl (45wt%)-KCl (55wt%) evenly to obtain a mixture;

Place 1 g of CoS ₂ and the above mixture in argon, keep at 400 ° C for 3 h, and cool;

The mixture was dissolved, filtered, and then dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Example 5:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Configure cobalt disulfide replacement molten salt carrier: mix 0.4g NiCl ₂ and 1g LiCl(22wt%)-LiBr(68.4wt%)-LiF(9.6wt%) evenly to obtain a mixture;

Put 0.5g CoS ₂ and the above mixture in argon, keep at 460°C for 10h, and cool;

The mixture was dissolved, filtered, and then dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Example 6:

A preparation method of cobalt disulfide material with high storage stability, comprising:

Configure cobalt disulfide replacement molten salt carrier: mix 0.4g NiCl ₂ , 1g LiF (0.67wt%)-LiBr (53.5wt%)-KBr (45.83wt%) uniformly to obtain a mixture;

Put 1.4g CoS ₂ and the above mixture in nitrogen, keep at 600°C for 1h, and cool;

The mixture was dissolved, filtered, and then dried in a vacuum oven at 80 °C for 24 h to obtain a CoS ₂ material with a shell structure.

Test example:

The cobalt disulfide material not treated by the method of the present invention and the cobalt disulfide material with storage stability treated by the method of the present invention are stored in air (100% humidity) for 170h respectively, and the materials before and after storage in the air are respectively stored for 170 hours. XRD analysis, the structure is shown in Figure 1;

It can be seen from Figure 1 that the untreated CoS ₂ is decomposed in large quantities after storage, while the CoS ₂ prepared in Example 1 of the present invention can still maintain the original crystal structure after storage, indicating that the CoS 2 prepared by the present invention After the above method, the storage stability of CoS ₂ is significantly improved, and it has a huge application prospect.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (5)

1. The preparation method of the cobalt disulfide material with high storage stability is characterized by comprising the following steps:

(1) the displacement reactants were formulated as follows:

taking at least one of water and alcohol as a solvent, adding acid and metal salt into the solvent, and uniformly stirring to prepare a cobalt disulfide precursor displacement solution; the concentration of the acid is 0.05-1 mol/L;

the molar ratio of the acid to the metal salt is 0.5-3: 1;

the metal salt is soluble metal salt;

(2) placing cobalt disulfide in a cobalt disulfide precursor displacement solution to prepare a suspension, placing the suspension at 120-240 ℃ under the condition of 10-60MP a, carrying out heat preservation reaction for 24-48 hours, and then cooling to obtain a cobalt disulfide material with high storage stability; wherein the concentration of the cobalt disulfide is 20-100 g/L;

alternatively, (1) the metathesis reaction was formulated as follows:

mixing at least one of lithium halide, sodium halide and potassium halide to obtain a mixture, adding metal salt into the mixture, and uniformly mixing to obtain a cobalt disulfide replacement molten salt carrier;

the lithium halide comprises at least one of LiF, LiCl and LiBr; the sodium halide comprises at least one of NaF, NaCl and NaBr;

the potassium halide comprises at least one of KF, KCl and KBr;

the lithium halide, the sodium halide and the potassium halide are contained in the mixture in a content of +/-5 wt% of the lowest eutectic point component of the mixture;

(2) mixing cobalt disulfide and a cobalt disulfide replacement molten salt carrier, placing the mixture in a non-oxidizing atmosphere environment at the temperature of 240-600 ℃, carrying out heat preservation reaction for 0.5-12 hours, cooling, and reacting to obtain a cobalt disulfide material with a shell structure; wherein the mass ratio of the cobalt disulfide to the cobalt disulfide replacement molten salt carrier is 1: 1-5.

2. The method for preparing cobalt disulfide material with high storage stability as claimed in claim 1, wherein cobalt disulfide is placed in a cobalt disulfide precursor displacement solution to prepare a suspension, and the suspension is placed at 180 ℃ and 10MP a for heat preservation reaction for 48 hours and then cooled to obtain the cobalt disulfide material with high storage stability;

wherein the concentration of the cobalt disulfide is 20-100 g/L.

3. The method for preparing cobalt disulfide material with high storage stability as claimed in claim 1, wherein:

the acid is at least one of hydrochloric acid, acetic acid, nitric acid, citric acid and sulfuric acid;

the soluble metal salt is soluble metal salt of Fe, Ni, Mn, Zr or Ti.

4. The cobalt disulfide material with high storage stability prepared by the method for preparing a cobalt disulfide material with high storage stability of any one of claims 1 to 3.

5. Use of the cobalt disulfide material with high storage stability of claim 4 in the preparation of electrode materials for thermal batteries, lithium batteries, solar cells, supercapacitors.

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