KR101527089B1 - THIN LAYER Mo-Chalcogenide AND METHOD FOR MANUFACTURING THEREOF - Google Patents

Abstract

The present invention relates to a process for producing a molybdenum chalcogenide intercalation compound in which molybdenum chalcogenide powder and an alkali metal salt or alkaline earth metal salt are mixed and heated so that alkali metal or alkaline earth metal ions are intercalated between layers, And removing the intercalated metal ions from the compound, and to a flaked molybdenum chalcogenide produced thereby.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a flaked molybdenum chalcogenide and a method for producing the same,

The present invention relates to a flaked molybdenum chalcogenide and a method of producing the same, and more particularly, to a method for producing flaky molybdenum chalcogenide using a molybdenum chalcogenide intercalation compound, and a method for producing the flake The present invention relates to molybdenum disulfide.

The two-dimensional nanostructured material has a uniform planar shape and is composed of one or several layers of atomic thickness. The two-dimensional nanostructured material is considered to be one of the most active fields of research in the field of chemistry and materials. This is a field where research topics are being diversified.

Representative two-dimensional nanostructured materials include graphene, hexagonal boron nitride (hBN), and molybdenum disulfide. The graphene has a structure in which one carbon atom in the sp2 bond is bonded to three different carbon atoms The hexagonal honeycomb-shaped graphite surface is a carbon isotope having a two-dimensional planar structure composed of a monolayer, and hexagonal boron nitride as an insulator is an ultra-thin dielectric material, and shows a great advantage as a substitute for conventional silica in manufacturing graphene devices .

On the other hand, molybdenum disulfide (MoS ₂ ) as another two-dimensional nanostructured material has electric and optical properties similar to graphene and is expected to be used as a field effect transistor due to its semiconductor characteristics. It has been recognized as an absorber and a light emitting material in various applications using light such as a photosensitizer.

Each of the S-Mo-S layers in the molybdenum disulfide (MoS ₂ ) is bound by weak van der Waals forces and, because of the interlayer interaction, has an electrical / optical property different from that of bulk MoS ₂ . For example, bulk MoS ₂ has an indirect bandgap of 1.2 eV, while a single layer has a direct bandgap of 1.8 eV. Recently, the field-effect transistor of MoS ₂ substrate shows a charge mobility of 200 cm ² / Vs and an on / off ratio exceeding 108.

In addition, in the case of molybdenum disulfide, since the S-Mo-S layer interacts weakly with other layers, it can be thinned by a chemical / physical method, and an ultra thin MoS ₂ crystal piece with a thickness of 0.65 nm can be obtained.

For example, as a thinning technique of molybdenum disulfide, Nano Lett., 2011, 11 (12), pp 5111-5116 discloses a method of making molybdenum disulfide flake using n-BuLi. However, the process is complicated, and the risk of n-BuLi and low yield remains a challenge.

As a method for producing flaked molybdenum disulfide, studies on the production of a large-area high-quality molybdenum disulfide by CVD (Chemical Vapor Deposition) have been attempted. The CVD method is advantageous in that MoS ₂ thickness control is easier than other technologies and is compatible with current industrial technologies. However, the CVD method has a disadvantage of high manufacturing cost due to a high temperature process, difficulty in mass production due to a narrow reactor space and difficulty in mass production of molybdenum disulfide The crystallinity is considerably low.

On the other hand, a technology for making a two-dimensional nanostructured material thin by using an inexpensive but stable compound such as an alkali metal salt is being studied without using an unstable but expensive compound such as n-BuLi.

For example, as a technology for making a material of a two-dimensional nanostructure thin, Japanese Laid-Open Patent Publication No. 2011-0106625 (Sep. 29, 2011) discloses a technique in which an alkali metal ion or an alkaline earth metal ion is inserted between graphite layers to form a graphite intercalation compound, From this, a technique for producing graphene which is a two-dimensional nanostructure is disclosed.

However, the above-mentioned prior art document is a technology for producing a single layer of graphene, and it is still required to research and develop a method for manufacturing a flaked material of molybdenum chalcogenide such as molybdenum disulfide in a simple process, more safely and economically Are continuously required.

Open Patent Publication No. 2011-0106625 (September 29, 2011)

Nano Lett., 2011, 11 (12), pp 5111-5116

In order to solve the above-mentioned problems, the present invention can produce a flaked molybdenum chalcogenide having a simpler process and a higher economical efficiency, and can produce a novel thin film capable of introducing various functional groups onto the surface of the obtained molybdenum disulfide. And a method for producing the molybdenum chalcogenide.

It is another object of the present invention to provide a flaked molybdenum chalcogenide having various functional groups on its surface, which is obtained by the process for producing the novel molybdenum chalcogenide.

According to the present invention, there is provided a method for producing a molybdenum chalcogenide intercalation compound comprising the steps of: a) mixing a molybdenum chalcogenide powder with an alkali metal salt or an alkaline earth metal salt and heating the molybdenum chalcogenide intercalation compound into which alkali metal or alkaline earth metal ions are intercalated; ; And b) removing the intercalated metal ions from the molybdenum chalcogenide intercalation compound. The present invention also provides a method for producing flaked molybdenum chalcogenide.

The present invention also provides a flaked molybdenum chalcogenide prepared according to the above described process. In this case, the flaked molybdenum chalcogenide may be flaked molybdenum disulfide (MoS ₂ ).

The flaked molybdenum chalcogenide obtained in the present invention can also be used as a semiconductor material.

The process for producing the flaked molybdenum chalcogenide according to the present invention is advantageous in that the reaction is carried out in a simpler process and stable reaction conditions and has a high economic efficiency.

According to the method of the present invention, it is possible to introduce various functional groups onto the surface of the flaked molybdenum chalcogenide.

FIG. 1 is a flow chart showing a method of manufacturing a flaked molybdenum chalcogenide according to an embodiment of the present invention.
2 is an X-ray diffraction (XRD) graph of a molybdenum chalcogenide intercalation compound according to an embodiment of the present invention.
FIG. 3 is a graph of X-ray photoelectron spectroscopy (XPS) measurement of a molybdenum chalcogenide intercalation compound according to an embodiment of the present invention.
4 is a graph of X-ray photoelectron spectroscopic (XPS) measurements of flaked molybdenum chalcogenide in accordance with an embodiment of the present invention.
Figure 5 shows the results of scanning probe microscopy (AFM) measurements of flaked molybdenum chalcogenide according to one embodiment of the present invention.
6 is measurement data of RT-IR spectroscopy of a flaked molybdenum chalcogenide according to an embodiment of the present invention.
7 shows the dispersibility of the flaked molybdenum chalcogenide in each of the solvents according to an embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a multi-layered structure of the present invention and a method of manufacturing the same will be described in detail with reference to the accompanying drawings. While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It is to be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but on the contrary, is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. In the accompanying drawings, the dimensions of the structures are enlarged to illustrate the present invention in order to clarify the present invention. Numbers (e.g., first, second, etc.) used in the description process of the present invention are merely an identifier for distinguishing one component from another.

Unless otherwise defined in this invention, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

FIG. 1 illustrates a method of manufacturing a flaked molybdenum chalcogenide according to an embodiment of the present invention.

As shown in FIG. 1, the present invention provides a method for manufacturing a semiconductor device, comprising: preparing a molybdenum chalcogenide powder and an alkali metal salt or an alkaline earth metal salt; Mixing the molybdenum chalcogenide powder with an alkali metal salt or an alkaline earth metal salt to produce molybdenum chalcogenide intercalation compound wherein the alkali metal or alkaline earth metal ion is intercalated between the layers; And removing the inserted metal ions from the molybdenum chalcogenide intercalation compound. The present invention also provides a method for producing flaked molybdenum chalcogenide.

In general, chalcogen refers to a nonmetallic element of group 16 of oxygen (O), sulfur (S), selenium (Se) and tellurium (Te), which can be made into a 1: 1 compound with an alkaline earth metal And can also react with the transition metal to provide a transition metal-chalcogenide consisting of at least one chalcogen element and at least one positive element.

Molybdenum chalcogenide in which molybdenum is combined with chalcogen as a transition metal in the transition metal-chalcogenide is a compound obtained by the combination of molybdenum with sulfur (S), selenium (Se) and tellurium (Te) MoS ₂ , MoSe ₂ and MoTe ₂ are representative compounds.

Such a molybdenum chalcogenide is a bond of chalcogen such as sulfur source (S) or the like in which the molecules are brought into contact with each other, so that a layered slip phenomenon can occur therein, thereby making it possible to reduce the thickness.

According to the present invention, in order to produce flaked molybdenum chalcogenide, an intercalation compound of molybdenum chalcogenide having alkali metal or alkaline earth metal ions intercalated thereinto is prepared through the thinning, and the alkali metal or alkaline earth metal ion Can be removed to produce flaky molybdenum chalcogenide.

The term "flaking" in the present invention means a structure of a single layer or a layer composed of several to several tens layers. Preferably a single layer, may be a material having a structure of 1 to 10 layers, more preferably a single layer, and may be a material having a structure of 1 to 7 layers.

At this time, the alkali metal salt or alkaline earth metal salt used in the present invention is a salt containing an alkali metal or an alkali earth metal and an anion corresponding thereto, and if alkali metal or alkaline earth metal can be inserted between the layers of the molybdenum chalcogenide, May be selected from organic carboxylic acid salts, alkoxy salts, hydroxyl salts, phenoxy salts, organic sulfonates, organic phosphates, sulfonates, phosphates, carbonates, halides and nitrates of alkali metals or alkaline earth metals, Lt; / RTI >

When the alkali metal salt and the alkaline earth metal salt in the present invention are any one or more selected from the group consisting of an organic carboxylic acid salt, an alkoxy salt, a phenoxy salt, an organic sulfonic acid salt, and an organic phosphate, they may each be an aliphatic hydrocarbon chain, an aromatic hydrocarbon ring, Or an aromatic heterocyclic group.

In this case, the chain of the aliphatic hydrocarbon is an alkyl group having 1 to 30 carbon atoms, the aromatic hydrocarbon ring is an aryl group having 6 to 40 carbon atoms, the aromatic heterocyclic group is a heteroaryl group having 2 to 40 carbon atoms, The carboxylate, alkoxylate, organic sulfonate and organic phosphate of the earth metal are each an alkyl group having 1 to 30 carbon atoms, an aromatic hydrocarbon ring having 6 to 40 carbon atoms as the chain of the aliphatic hydrocarbon, or an aryl group having 6 to 40 carbon atoms as the aromatic heterocyclic group, Lt; RTI ID = 0.0 > Cl-40 < / RTI > heteroaryl groups.

For example, when the alkali metal salt or alkaline earth metal salt in the present invention is lithium as an alkali metal and the corresponding anion is an anion of an organic carboxylic acid, the organic carboxylic acid may be an alkyl group having 1 to 30 carbon atoms, An aryl group having 1 to 40 carbon atoms, a heteroaryl group having 2 to 40 carbon atoms, and the like.

As another example, when the alkali metal salt or alkaline earth metal salt in the present invention is calcium as the alkaline earth metal and the corresponding anion has an alkoxy group, the alkoxy group may be an alkyl group having 1 to 30 carbon atoms, an alkyl group having 6 to 40 carbon atoms An aryl group, and a heteroaryl group having 2 to 40 carbon atoms.

Here, the aryl group used in the present invention is an organic radical derived from an aromatic hydrocarbon by the removal of one hydrogen, and includes a single or fused ring system containing 5 to 7, preferably 5 or 6, When a substituent is present in an aryl group, it may be fused with an adjacent substituent to form a ring. At least one hydrogen atom of the aryl group may be substituted with a substituent selected from the group consisting of a deuterium atom, a halogen atom, a hydroxy group, a nitro group, a cyano group, , An amino group, a carboxyl group, a sulfonic acid group, a phosphoric acid group, an alkyl group having 1 to 24 carbon atoms, a halogenated alkyl group having 1 to 24 carbon atoms, an alkenyl group having 1 to 24 carbon atoms, an alkynyl group having 1 to 24 carbon atoms, An aryl group having 6 to 24 carbon atoms, an arylalkyl group having 6 to 24 carbon atoms, a heteroaryl group having 2 to 24 carbon atoms, or a heteroaryl group having 2 to 24 carbon atoms It means that which may be substituted with a keel.

Specific examples of the aryl include phenyl, naphthyl, biphenyl, terphenyl, anthryl, indenyl, fluorenyl, phenanthryl, triphenylenyl, pyrenyl, perylenyl, crycenyl, naphthacenyl, fluororan And the like, but are not limited thereto.

In the present invention, the alkyl group is an organic radical derived from an aliphatic hydrocarbon by elimination of one hydrogen. The alkyl group may include a linear or branched structure, and it should also be considered to include a cyclic alkyl group.

At least one hydrogen atom of the alkyl group may be substituted with the same substituent as the aryl group.

Specific examples of the alkyl include, but are not limited to, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, pentyl, isopentyl, 2-ethylhexyl, cyclopentyl, cyclohexyl, t-butyl and the like.

Also, in the present invention, the heteroaryl group means a heteroaromatic organic radical having 2 to 24 carbon atoms which may contain 1 to 4 hetero atoms selected from N, O, P or S in each ring in the aryl group, The rings may be fused to form a ring, and at least one hydrogen atom of the heteroaryl group may be substituted with the same substituent as the aryl group.

In the present invention, the alkali metal may be any one selected from the group consisting of lithium, sodium, potassium, rubidium (Rb), and cesium and may be used in combination. Examples of the alkaline earth metal include beryllium, magnesium, calcium, strontium, One or a mixture thereof may be used.

The flaked molybdenum chalcogenide that can be produced in the present invention can be obtained by the production method of the present invention without limitation of the type of the powder that can be obtained by the combination of molybdenum and chalcogen, ₂ , MoSe ₂ , MoTe ₂ , and the like.

As a first step for preparing the flaked molybdenum chalcogenide in the present invention, in order to produce an intercalation compound of molybdenum chalcogenide having intercalated alkali metal or alkaline earth metal ions, a molybdenum chalcogenide powder and an alkali metal salt or And mixing and heating the alkaline earth metal salt.

The mixing ratio of the molybdenum chalcocene powder to the alkali metal salt or the alkaline earth metal salt may be in the range of 1: 1 to 1:20 by weight, preferably 1: 1 to 1: 5.

If the content of the molybdenum chalcocene powder is greater than the above range, the formation of the intercalation compound may become difficult. If the content of the alkali metal salt or the alkaline earth metal salt is increased, the salt removal and the cost are increased.

In the present invention, the mixed molybdenum chalcocene powder and the alkali metal salt or alkaline earth metal salt may be uniformly melted by heating. For this, the heating temperature may be 70 ° C to 400 ° C, preferably 150 ° C to 300 ° C.

If it is lower than the above range, the molybdenum chalcogenide powder and the alkali metal salt or alkaline earth metal salt are uniformly melted and it is difficult for the alkali metal or alkaline earth metal to be intercalated between the layers. If the temperature is higher than the above range, Or by-products may be generated in many cases, which is disadvantageous in a mass production process.

In the present invention, the alkali metal salt or alkaline earth metal salt may each include a salt in the form of a hydrate. In this case, the alkali metal salt or alkaline earth metal salt may be composed only of the salt of the hydrate form, or may be a salt of the anhydrous metal salt having a hydrate form of 30 wt% or more, preferably 50 wt% or more, more preferably 70 wt% Hydrate form. ≪ / RTI >

If the alkali metal salt or alkaline earth metal salt is in the form of a hydrate as described above, the raw materials (the molybdenum chalcogenide powder and the alkali metal salt or the alkaline earth metal salt) are mixed at a lower temperature than that using only a hydrate- There is an advantage that it can be melted.

That is, in order to uniformly heat and melt the alkali metal salt or alkaline earth metal salt and the molybdenum chalcogenide powder when they are mixed and heated, the alkali metal ions (Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ ) or the alkaline earth metal It can be melted by heating to a temperature higher than the melting point of a salt containing an ion (Be ²⁺ , Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ ). In the present invention, however, by using a metal salt hydrate There is an advantage that molybdenum chalcogenide intercalation compounds in which alkali metal or alkaline earth metal ions are intercalated between layers can be produced under more stable conditions.

Examples of hydrates of alkali metal or alkaline earth metal ions that can be used in the present invention include sodium acetate trihydrate (NaC ₂ H ₃ CO ₂ .3H ₂ O), sodium carbonate heptahydrate (Na ₂ CO ₃ .7H ₂ O), sodium citrate pentahydrate (Na ₃ C ₆ H ₅ O ₇ .5H ₂ O), sodium orthophosphate dodecahydrate (Na ₃ PO ₄ . 12H ₂ O), magnesium and sodium tartrate decahydrate (Na ₂ SO ₄ .7H ₂ O), sodium sulfate decahydrate (Na ₂ SO ₄ .10H ₂ O) , Potassium-magnesium sulfate hexahydrate (K ₂ SO ₄ MgCl ₂ .6H ₂ O), calcium acetate dihydrate (Ca (C ₂ H ₃ O ₂ ) ₂ .6H ₂ O), calcium carbonate hexahas Deureyiteu _{(Calcium carbonate hexahydrate (CaCO 3 .6H} 2 O)), calcium chloride hexahydrate _{(Calcium chloride hexahydrate (CaCl 2 .6H} 2 O)), calcium citrate la ted hydrate _{(Calsium citrate tetrahydrate (Ca 3 [} O 2 CCH ₂ C (OH) (CO ₂ ) CH ₂ CO ₂ ] ₂ .4H ₂ O), calcium lactate pentahydrate (Ca (C ₅ H ₃ O ₃ ) ₂ .5H ₂ O) nitrate trihydrate (calcium nitrate trihydrate (Ca (NO 3) 2 .3H 2 O)), calcium sulfate dihydrate _{(calcium sulfate dihydrate (CaSO 4 .2H} 2 O)), magnesium acetate tetrahydrate (magnesium acetate tetrahydrate (Mg (C ₂ H ₃ O ₃ ) ₂ .4H ₂ O), magnesium carbonate pentahydrate (MgCO ₃ .5H ₂ O), magnesium acetate trihydrate (Mg (C ₃ H ₅ O ₂ ) ₂ .3H ₂ O), magnesium nitrate hexahydrate (Magnesium n _{itrate hexahydrate (Mg (NO 3)} 2 .6H 2 O)), magnesium ortho-phosphate octa-hydrate (Magnesium orthophosphate octahydrate (Mg (PO 4) 2 .8H 2 O)), magnesium sulfate hepta-hydrate (Magnesium sulfate heptahydrate (MgSO ₄ 7H ₂ O), magnesium tartrate pentahydrate (MgC ₄ H ₄ O ₆ .5H ₂ O) and sodium carbonate decahydrate (Na ₂ CO ₃ .10H ₂ O) One or more selected mixtures may be used.

The second step for preparing the flaked molybdenum chalcogenide in the present invention is a step for removing the metal ions inserted from the molybdenum chalcogenide intercalation compound by dispersing the resulting molybdenum chalcogenide intercalation compound in a solvent, The inserted metal ions can be removed.

The step used to remove the intercalated metal ions may be removed by dissolving the intercalation compound in a solvent comprising an alcohol, ketone, ether, amide, water or mixtures thereof, but is not limited thereto.

Illustrative examples of the solvent include water, ethanol, methanol, isopropanol, formamide, dimethylsulfoxide, dimethylformamide, acetic acid, acetonitrile, methoxyethanol, tetrahydrofuran, benzene, xylene, toluene and cyclohexane Can be used.

More preferably, when the molybdenum chalcogenide intercalation compound containing the metal ion is dispersed in an alcohol or an aqueous solution having a hydroxyl group (-OH) or a mixture thereof, metal ions (Na ⁺ or K ⁺ ) are dissolved At the same time, the molybdenum chalcogenide intercalation compound is flaked into several layers to produce flaky molybdenum chalcogenide.

At this time, an ultrasonic process may be additionally introduced to selectively improve the slimming and the solubility of metal ions. Thereby making it possible to produce more effectively flaked molybdenum chalcogenide.

In the present invention, the step of removing the inserted metal ions from the molybdenum chalcogenide intercalation compound is followed by redispersing the obtained flaky molybdenum chalcogenide in a solvent, wherein the flaked molybdenum chalcogenide And a manufacturing method thereof.

The re-dispersion step can provide flaked molybdenum chalcogenide from which the by-product in the flaking process has been removed in the previous step. In addition, depending on the kind of the solvent, the pH, or the type of the additive additionally contained in the solvent The electrical or optical properties of the dispersed flaky molybdenum chalcogenide can be controlled or modified.

The present invention also provides a flaked molybdenum chalcogenide prepared according to the above described process.

The flaked molybdenum chalcogenide may be, for example, a flaked molybdenum chalcogenide, denoted MoS ₂ , MoSe ₂ , MoTe ₂ , and the flaked molybdenum chalcogenide may be an electronic material and a semiconductor material Can be applied.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT It is to be understood that this is by way of example only and not to be construed as limiting the scope of the invention in any way whatsoever.

(Example)

Synthesis of flaked materials

Example 1.

1.1 Manufacture of molybdenum chalcogenide intercalation compounds

1 g of sodium potassium tartrate hydrate (tetrahydrate) and 0.1 g of molybdenum disulfide powder were mixed and heated at 250 캜 for 24 hours to prepare 1 g of a molybdenum disulfide intercalation compound. At this time, it can be seen that the black molybdenum disulfide powder turns yellowish brown when it becomes an intermolecular disulfide molybdenum compound.

1.2 Manufacture of flaky molybdenum chalcogenide

1 g of the molybdenum disulfide intercalation compound prepared in 1.1 was dissolved in 25 ml of ethanol, and the mixture was ultrasonically softened for 10 minutes to obtain 0.5 g of thinned molybdenum disulfide.

1.3. Flaked molybdenum chalcogenide redispersions

20 mg of the flaked molybdenum disulfide prepared in 1.2 above was dispersed in 20 ml of aqueous solution for 1 hour using ultrasonic waves. The dispersed sliced molybdenum disulfide was allowed to stand at room temperature for 3 weeks and then its dispersibility was confirmed.

Examples 2 to 12

(Example 2), ethanol (Example 3), methanol (Example 4), isopropyl alcohol (Example 5) as a polar or non-polar solvent in place of the aqueous solution in the redispersion step, ), Pyridine (Example 6), THF (Example 7), toluene (Example 8), benzene (Example 9), chloroform (Example 10, DMSO (Example 11), DMF The experiment was carried out using.

In the following Table 1, acetone (Example 2), ethanol (Example 3), methanol (Example 4), isopropyl alcohol (Example 5), pyridine (Example 6), THF (Mg / ml) in benzene (Example 9), benzene (Example 9), chloroform (Example 10, DMSO (Example 11), DMF (Example 12)

[Table 1]

Evaluation of physical properties of flaky materials

2 is an X-ray diffraction (XRD) graph of an intercalation compound in which potassium ion (K ⁺ ) as an alkali metal ion is inserted between molybdenum disulfide layers according to Example 1 above.

In detail, the molybdenum disulfide intercalation compound was expanded to 1.98 Å due to the K ⁺ ion rather than the molybdenum disulfide before the reaction.

3 and 4 are X-ray photoelectron spectroscopic (XPS) measurement graphs of the molybdenum chalcogenide intercalation compound and the flaked molybdenum chalcogenide according to Example 1 of the present invention, respectively, and the molybdenum chalcogenide The surface characteristics of the interlayer compound and the flaked molybdenum chalcogenide were confirmed.

More specifically, in the case of the flaked molybdenum disulfide of FIG. 4, it can be seen that the binding energy is increased (see arrows) compared to the intermolecular disulfide molybdenum compound. This is because, in the case of the molybdenum disulfide intercalation compound, Na ^+, K ^{+, and} so on are intercalated into the interlayer, and binding energy of the intercalated compound of molybdenum chalcogenide is reduced.

Fig. 5 is an analysis graph of the scanning probe microscope (AFM) of the flaked molybdenum disulfide prepared in Example 1. Fig. This confirms that flaked molybdenum disulfide is formed.

FIG. 6 is a FT-IR analysis graph of the flaked molybdenum disulfide produced in Example 1, and it can be confirmed that the flaked molybdenum disulfide obtained by the present invention has the same peak as that of the alkali metal hydrate, It can be seen that the flaked molybdenum disulfide is functionalized with an organic group contained in the alkali metal hydride through the alkali metal hydride.

FIG. 7 shows the dispersibility of the molybdenum disulfide prepared in each of Examples 1 to 12 according to the respective solvents. The molybdenum disulfide dispersed in each solvent was observed after storage for 3 weeks. As a result, It can be confirmed that the dispersibility is maintained.

Based on the above analysis data, it can be seen that the molybdenum chalcogenide thinned at a low temperature can be mass-produced by a safer and simpler process using the alkali metal salt or alkaline earth metal salt in the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the appended claims.

Claims (15)

a) preparing a molybdenum chalcogenide intercalation compound in which molybdenum chalcogenide powder and an alkali metal salt or alkaline earth metal salt are mixed and heated so that the alkali metal or alkaline earth metal ion is intercalated between layers; and
b) removing the intercalated metal ions from the molybdenum chalcogenide intercalation compound,
The alkali metal salt or alkaline earth metal salt may be at least one selected from the group consisting of an organic carboxylic acid salt, an alkoxy salt, a hydroxyl salt, a phenoxy salt, an organic sulfonate, an organic phosphate, a sulfonate, a phosphate, ego,
When the alkali metal salt or the alkaline earth metal salt is any one or more selected from the group consisting of an organic carboxylic acid salt, an alkoxy salt, a phenoxy salt, an organic sulfonic acid salt and an organic phosphate, any one selected from a chain of an aliphatic hydrocarbon, an aromatic hydrocarbon ring or an aromatic heterocyclic group Characterized in that it comprises at least one functional group. ≪ RTI ID = 0.0 > 11. < / RTI > delete delete The method according to claim 1,
The chain of the aliphatic hydrocarbon is an alkyl group having 1 to 30 carbon atoms,
The aromatic hydrocarbon ring is an aryl group having 6 to 40 carbon atoms,
Wherein the aromatic heterocyclic group is a heteroaryl group having 2 to 40 carbon atoms. The method according to claim 1,
Further comprising the step of redispersing the resulting flaky molybdenum chalcogenide in a solvent after the step of removing the inserted metal ions from the molybdenum chalcogenide intercalation compound and a process for producing flaky molybdenum chalcogenide . The method according to claim 1,
Wherein the molybdenum chalcogenide is any one selected from MoS ₂ , MoSe ₂ , and MoTe ₂ . The method according to claim 1,
Wherein said alkali metal salt or alkaline earth metal salt comprises a salt in the form of a hydrate, respectively. 8. The method of claim 7,
Wherein the alkali metal salt or the alkaline earth metal salt is composed only of a salt in the form of a hydrate, or the salt of the alkali metal salt or the alkaline earth metal salt is in a form of a hydrate of at least 50 wt%. 8. The method of claim 7,
The hydrates of the alkali metal salt or alkaline earth metal salt are sodium acetate trihydrate (NaC ₂ H ₃ CO ₂ .3H ₂ O), sodium carbonate heptahydrate (Na ₂ CO ₃ .7H ₂ O ), Sodium citrate pentahydrate (Na ₃ C ₆ H ₅ O ₇ .5H ₂ O), sodium orthophosphate dodecahydrate (Na ₃ PO ₄ .12H ₂ O)), sodium orthophosphate dodecahydrate Magnesium and sodium tartrate decahydrate (Na ₂ SO ₄ .7H ₂ O), sodium sulfate decahydrate (Na ₂ SO ₄ .10H ₂ O), potassium-magnesium sulfate hexa (Calcium and calcium sulfate hexahydrate (K ₂ SO ₄ MgCl ₂ .6H ₂ O)), calcium acetate dihydrate (Ca (C ₂ H ₃ O ₂ ) ₂ .6H ₂ O)), calcium carbonate Calcium carbonate hexa hydrate (CaCO ₃ .6H ₂ O)), calcium chloride hexahydrate (CaCl ₂ .6H ₂ O), calcium citrate tetrahydrate (Ca ₃ [O ₂ CCH ₂ C ) (CO ₂ ) CH ₂ CO ₂ ] ₂ .4H ₂ O), Calcium lactate pentahydrate (Ca (C ₅ H ₃ O ₃ ) ₂ .5H ₂ O)), calcium nitrate trihydrate (calcium nitrate trihydrate (Ca (NO 3) 2 .3H 2 O)), calcium sulfate dihydrate _{(calcium sulfate dihydrate (CaSO 4 .2H} 2 O)), magnesium acetate tetrahydrate (magnesium acetate tetrahydrate (Mg (C 2 H ₃ O ₃ ) ₂ .4H ₂ O), magnesium carbonate pentahydrate (MgCO ₃ .5H ₂ O), magnesium acetate trihydrate (Mg (C ₃ H ₅ O ₂ ) ₂ . 3H ₂ O), magnesium nitrate hexahydrate (Mg (NO ₃ ) ₂ .6H ₂ O ), Magnesium orthophosphate octahydrate (Mg (PO ₄ ) ₂ .8H ₂ O), magnesium sulfate heptahydrate (MgSO ₄ .7H ₂ O), magnesium tartrate pentahydrate Characterized in that it is at least one selected from the group consisting of magnesium tartrate pentahydrate (MgC ₄ H ₄ O ₆ .5H ₂ O) and sodium carbonate decahydrate (Na ₂ CO ₃ .10H ₂ O) ≪ / RTI > The method according to claim 1,
Wherein the molar ratio of the molybdenum chalcogenide powder to the alkali metal salt or alkaline earth metal salt is in the range of 1:10 to 10: 1 by weight. The method according to claim 1,
Wherein the heating temperature is 70 ° C to 400 ° C. The method according to claim 1,
The step of removing the inserted metal ions from the molybdenum chalcogenide intercalation compound is characterized in that metal ions are removed by dissolving the intercalation compound in a solvent comprising alcohol, ketone, ether, amide, water or a mixture thereof , A method for producing flaky molybdenum chalcogenide. delete delete delete

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