KR20140076473A - Electrochemical device - Google Patents

Abstract

Provided is an electrochemical device which includes an anode where an anode active material is oxygen, a cathode where a cathode active material is a material of absorbing and discharging lithium ions, and an electrolyte which contains an oxygen absorption and desorption material whose oxygen combination rate is within 60-95% under pure oxygen. The electrochemical device can effectively supply oxygen into an electrolyte.

Description

      [0001] Electrochemical device [0002]

A cathode having oxygen as a cathode active material, a cathode having a material capable of intercalating and deintercalating lithium ions as a negative electrode active material, and an electrolytic solution.

BACKGROUND ART An electrochemical device including a positive electrode containing oxygen as a positive electrode active material, a negative electrode comprising a material capable of absorbing and desorbing lithium ions as a negative electrode active material, and an electrolyte is a next generation electrochemical device.

In order to improve the performance of the electrochemical device, it is necessary to supply a large amount of oxygen to the electrolytic solution to facilitate the redox reaction in the electrode.

Generally, the oxygen used as the cathode active material of the electrochemical device can be supplied from a gas canister or ambient air. However, when oxygen is supplied from the gas cylinder, the volume of the electrochemical device may increase or the weight may increase. In the case of supplying oxygen from the ambient air, it is necessary to remove impurities other than oxygen from the air. The amount may be insufficient.

Therefore, in order to improve the performance of such an electrochemical device, it is necessary to add a new substance capable of efficiently supplying oxygen in the electrolytic solution.

  An aspect of the present invention is to provide an electrochemical device including an electrolyte capable of easily forming an oxygen complex and containing an oxygen absorbing / desorbing material excellent in oxygen adsorption / desorption capability in an electrolyte to improve the amount of oxygen supplied to the electrolyte.

  According to one aspect,

A cathode having oxygen as a cathode active material;

A negative electrode comprising a negative electrode active material capable of intercalating and deintercalating lithium ions; And

There is provided an electrochemical device comprising an oxygen adsorption / desorption material having an oxygen bonding rate of 60 to 95% under pure oxygen and an electrolyte containing a solvent.

The oxygen absorbing / desorbing material may be a tetraphenylporphyrin derivative having a structure in which the axial ligand of the high electron donor is coordinated to the fifth position and the pivalent group is bonded to the sixth positional direction.

The oxygen absorbing / desorbing material may be a tetraphenylporphyrin derivative in which oxygen molecules are coordinately bonded to the sixth position.

The oxygen absorbing / desorbing material may include a tetraphenylporphyrin-metal complex.

The axial ligand of the high electron donor may include amines, imines, imidazoles, or ethers.

The axial ligand of the high electron donor may comprise a nitrogen-containing organic ligand.

The content of the oxygen absorbing / desorbing material may be 0.1 to 3 parts by weight based on 100 parts by weight of the solvent.

The electrolytic solution may further include a support salt.

The support salt may be at least one of lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and lithium bis (pentafluoroethanesulfonyl) imide (LiBETI) It can be all day.

The electrochemical device may be a lithium air battery.

An electrochemical device comprising an anode comprising oxygen as a cathode active material, a cathode comprising a metal as a negative electrode active material, and an electrolyte containing oxygen adsorbing / desorbing material and solvent having oxygen bond rate of 60 to 95% under pure oxygen, It can supply efficiently.

1 is a schematic diagram showing that an oxygen adsorptive and desorbing material in an electrolyte of an electrochemical device forms an oxygen complex by coordinating with oxygen.
2 is an example of a tetrapyropallyophenylporphyrin-cobalt complex (CoTpivPP).
3 is a schematic diagram illustrating a lithium air cell according to one embodiment.

Hereinafter, the electrochemical device according to one embodiment will be described in detail. The present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

In one aspect, a cathode comprising oxygen as a cathode active material; A negative electrode comprising a negative electrode active material capable of intercalating and deintercalating lithium ions; And an electrolytic solution containing an oxygen absorbing / desorbing material and a solvent having an oxygen bonding ratio of 60 to 95% under pure oxygen.

The electrolytic solution used in the electrochemical device contains an oxygen absorbing / desorbing material having an oxygen binding rate of 60 to 95% under pure oxygen.

The oxygen adsorbing and desorbing material may be a tetraphenylporphyrin derivative having a structure in which an axial ligand of a high electron donor is coordinated to a fifth position and a pivaloyl group is bonded to a sixth positional direction.

The oxygen absorbing / desorbing material may be a tetraphenylporphyrin derivative in which oxygen molecules are coordinately bonded to the sixth position.

1 is a schematic diagram showing that an oxygen adsorptive and desorbing material in an electrolyte of an electrochemical device forms an oxygen complex by coordinating with oxygen.

Referring to FIG. 1, the tetraphenylporphyrin derivative positioned in the electrolyte of the electrochemical device has a pivaloyl group in the 6-position, and oxygen molecules are bound to the pivaloyl group by the steric effect of the pivotal group. It is structured to be surrounded by the diary. Thus, it can be seen that oxygen molecules are coordinated to the sixth position of the tetraphenylporphyrin derivative with a high binding force to easily form an oxygen complex.

The oxygen absorbing / desorbing material may include a tetraphenylporphyrin-metal complex.

The tetraphenylporphyrin-metal complex can dissolve an oxygen absorbing and desorbing material containing the structure in which a pivaloyl group is bonded at a predetermined position in an electrolyte to improve the oxygen desorbing ability in the electrolyte. As a result, at the time of discharging at a high current, oxygen deficiency in the electrolyte can be supplemented by supplying oxygen in the electrolyte solution by releasing oxygen from the oxygen absorbing / desorbing material.

The oxygen adsorbing and desorbing material may include, for example, tetrapyropallyophenylporphyrine-cobalt complex (CoTpivPP), or diisophthalimide tetraphenylporphyrine-cobalt complex (CoThthPP).

2 is an example of a tetrapyropallyophenylporphyrin-cobalt complex (CoTpivPP). The tetrapivaloylphenylporphyrin-cobalt complex (CoTpivPP) is obtained by bonding a pivaloyl group in the sixth positional direction.

The oxygen adsorbing / desorbing material is a tetraphenylporphyrin derivative having a structure in which a pivotal group is bonded to the tetraphenylporphyrin-metal complex, and an axial ligand of a high electron donor is coordinated at the fifth position of the metal. Thereby, coordination of oxygen molecules to the sixth position on the opposite side of the metal of the tetrapyobalylphenylporphyrin derivative can be promoted.

The axial ligand of the highly electron donor may be an amine such as methylamine, trimethylamine, etheramine, pyridine, hexamethylenediamine, morpholine or aniline, an amine such as ethyleneamine or Schiff base, , Imidazoles such as benzylimidazole and trimethylimidazole, and ethers. For example, imidazoles such as methylimidazole, benzylimidazole, and trimethylimidazole are preferable for increasing the oxygen affinity of porphyrin derivatives.

The axial ligand of the high electron donor may include a nitrogen-containing organic ligand having an amino group, a phosphino group, a carboxyl group, a thiol group, etc., and may include triphenylphosphine, acetylacetonate, and the like.

On the other hand, the oxygen adsorbing / desorbing material can adsorb 1 mol of the high-electron donor coordinator to 1 mol of the tetraphenylporphyrin-metal complex. Thus, for example, when benzylimidazole having a molecular weight of 158 is reacted with a tetrapyropallylphenylporphyrin-cobalt complex (CoTpivPP) having a molecular weight of 1068, 100 parts by weight of tetrapivaloylphenylporphyrin-cobalt complex (CoTpivPP) Up to 15 parts by weight of benzylimidazole can be adsorbed.

The oxygen absorbing / desorbing material may have an oxygen binding rate under a pure oxygen of 60 to 95%, for example, 65 to 95%.

The oxygen binding rate can be obtained by analyzing the absorbance of the oxygen absorbing / desorbing material obtained by the UV-vis spectrum measurement from the Drago equation represented by the following formula (1): < EMI ID =

[Equation 1]

The oxygen binding rate will be described below taking as an example a tetraphenylpolypyrin-cobalt derivative (CoTpivPP-MeIm) in which 1-methylimidazole is coordinated at the fifth position.

In the calculation of the oxygen binding rate, UV-vis spectrum measurement of tetrapyropallyophenylporphyrin-cobalt derivative (CoTpivPP-MeIm) is carried out by first supplying a temperature condition of 25 占 폚, pure nitrogen and optional oxygen partial pressure. A-net absorbance under nitrogen and absorbance under A _1, any partial pressure of oxygen by A ₂ and, A, there is a difference between the ₁ and A ₂ (A _1, A ₂₎ in the absorption band of a handsome 551nm updated by the oxygen supply ㅿA. Since the Equation 1 in [Co] DELTA ε _b is an integer P _O2 vs. (P _O2 / ㅿ A), and an oxygen affinity parameter p ₅₀ is obtained by p ₅₀ = K ^-1 .

The lower the value of the oxygen affinity parameter p ₅₀ , the higher the oxygen affinity. An example of the oxygen affinity parameter p ₅₀ value of the tetraphenylporphyrin derivative coordinated with imidazoles as the axial ligand of a highly electron donor is 20 cmHg for the benzylimidazole, Imidazole is 23 cmHg, 1-methylimidazole is 31 cmHg, and imidazole is 43 cmHg.

DELTA A is due to increase in proportion to the oxygen binding ratio, p ₅₀ may be oxygen binding ratio of the porphyrin derivatives is calculated at each of the oxygen partial pressure by DELTA A.

As an example of the oxygen binding rate of the oxygen absorbing / desorbing material used in the present invention under the temperature condition of 25 ° C and pure oxygen, the oxygen binding rate of the oxygen absorbing / desorbing material coordinated with benzylimidazole as the axial ligand of the highly electron donating material is 91 , 79% for tritylimidazole, 67% for 1-methylimidazole, and 64% for imidazole.

The oxygen absorbing / desorbing material can improve the oxygen absorbing / desorbing ability by merely dissolving a small amount of the oxygen absorbing / desorbing material in the electrolyte solution. The content of the oxygen absorbing / desorbing material may be, for example, 0.1 to 3 parts by weight based on 100 parts by weight of the solvent. When the oxygen absorbing / desorbing material having the content within the above range is contained in the electrolyte, the oxygen concentration in the electrolyte can be increased by about 5 to 10 times as compared with the electrolyte containing no oxygen absorbing / desorbing material. Thus, the electrochemical device including the electrolytic solution containing the oxygen absorbing / desorbing material can improve the oxygen supply amount to the electrodes such as the anode and the cathode, and enables the operation at the high current at the time of discharging.

However, if necessary, the oxygen absorbing / desorbing material may be contained in the electrolytic solution until the saturation dissolution amount is attained within a range that does not impair the electrical characteristics of the electrochemical device of the present invention.

A lithium air battery will be described as an example of the above electrochemical device.

3 is a schematic diagram illustrating a lithium air battery 100 according to one embodiment.

3, the lithium air battery 100 includes an anode 110, a cathode 120, and an electrolyte 130 disposed between the anode 110 and the cathode 120.

The anode 110 includes a current collector 111 and a catalyst layer 112, and oxygen is used as a cathode active material. The current collector 111 is porous and can serve as a gas diffusion layer capable of diffusing air, and is not particularly limited as long as it has conductivity. Examples thereof include stainless steel, nickel, aluminum, iron, titanium, and carbon. As the shape of the current collector 111, for example, a thin film, a plate, a mesh, and a grid may be used, and more specifically, a mesh may be used. The mesh shape is suitable because of its excellent current collection efficiency.

The catalyst layer 112 may be made of platinum, gold, silver, manganese oxide, iron oxide, and the like. For example, donor and fullerene derivatives such as electron donors having a porphyrin ring as a reducing catalyst, And may include molecules joined by an electrically conductive spacer through an acceptor. The donor may be, for example, a compound having a substituted or unsubstituted porphyrin ring, for example, a porphyrin-metal complex substituted with Mg or Ni. Here, the substituent may be, for example, a C1-C10 alkyl group, a C1-C10 alkynyl group or a C6-C10 aryl group. The above-mentioned acceptor may be, for example, a derivative having a fullerene skeleton such as C60, C70, C74, C76 or the like, and the spacer may be, for example, a condensed nitrogen-containing heterocycle or a hydrocarbon ring. However, in addition to the above catalyst, it is possible to use all the catalysts that can be used as the catalyst layer of the anode having oxygen as the cathode active material.

The anode 110 may be appropriately added with a conductive material, a binder, a dispersant, a thickener, and the like. The conductive material is not limited as long as the electrochemical performance of the electrochemical device of the present invention is not impaired, and the material is not limited as long as it is an electron conductive material. Specifically, natural graphite, carbon black, ketjen black, carbon fiber and the like can be exemplified. These conductive materials may be used alone or in combination. As the binder, any material capable of bonding the active material and the conductive material can be used without limitation. Specifically, fluorine resins such as polytetrafluoroethylene and polyvinylidene fluoride, thermoplastic resins such as polypropylene, and the like can be listed. The content of the binder is not particularly limited and can be, for example, 30 wt% or less, and more specifically, 1 to 10 wt%.

The cathode 120 includes a current collector (not shown) and a negative electrode active material.

The current collector of the negative electrode is not particularly limited as long as it has conductivity. For example, copper, stainless steel, nickel, and the like. Examples of the shape of the current collector of the negative electrode include a thin film, a plate, a mesh, and a grid.

The negative electrode active material may be any material capable of intercalating and deintercalating lithium ions such as lithium, lithium oxide, and lithium alloy. For example, lithium metal can be used.

The cathode 120 may appropriately contain a conductive material, a binder, a dispersant, a thickener, and the like. At this time, the conductive material, the binder, the dispersing agent, and the thickening agent to be used may be the same kind and content as those of the anode 110.

The positive electrode 110 and the negative electrode 120 may be mixed and dispersed in an appropriate solvent to form a paste-like cathode material and an anode material. In addition to the positive electrode active material and the negative electrode active material, a conductive material and a binder may be appropriately added to the positive electrode material and the negative electrode material. The obtained positive electrode material and negative electrode material can be applied to the surface of the collector to form a negative electrode layer.

The electrolytic solution 130 may be an aqueous electrolytic solution, a non-aqueous electrolytic solution, or a polymer gel electrolytic solution, etc., as long as it can conduct metal ions of the negative electrode active material and dissolve the oxygen absorbing / desorbing material .

The electrolyte 130 contains an oxygen absorbing / desorbing material having an oxygen binding rate of 60 to 95% under pure oxygen as described above. The oxygen absorbing / desorbing material may be a tetraphenylporphyrin derivative having a structure in which the axial ligand of the high electron donor is coordinated to the fifth position and the pivalent group is bonded to the sixth positional direction. The oxygen absorbing / desorbing material may be a tetraphenylporphyrin derivative in which oxygen molecules are coordinately bonded to the sixth position. By containing the oxygen absorbing / desorbing material in the electrolyte solution 130, the electrolyte 130 can reversibly absorb and desorb oxygen by side reaction.

As the electrolyte 130, for example, a non-aqueous electrolyte can be used.

Examples of the solvent for the non-aqueous liquid electrolyte include cyclic carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate and vinylene carbonate, chain carbonates such as diethyl carbonate, dimethyl carbonate and ethyl methyl carbonate, gamma butyrolactone, gamma Cyclic ethers such as tetrahydrofuran, 2-methyltetrahydrofuran and the like, chain ethers such as dimethoxyethane and ethylene glycol dimethyl ether, and the like, as well as chloroethylene carbonate, fluoroethylene carbonate, 3- A known organic solvent such as methoxypropionitrile, trimethyl phosphate, triphenyl phosphate, sulfolane, and dimethylsulfoxide may be used.

Further, it is also possible to use N, N-diethyl-N-ethyl-N- (2-methoxyethyl) ammonium bis (trifluorosulfonyl) imide, N-methyl-N-propylpiperidium bis Ionic liquids such as imide, 1-methyl-3-propylimidazolium imide (trifluorosulfonyl) imide, and 1-ethyl-3-butyl imidazolium tetrafluoroborate . These solvents may be used alone or in combination of two or more.

The electrolytic solution may further include a support salt. The support salt may be dissolved in the solvent and act as a source of lithium ions in the cell. As the supporting salt, for example, there may be mentioned hexafluorophosphone salt (LiPF ₆ ), perchlorate salt (LiClO ₄ ), tetrafluoroborate salt (LiBF ₄ ), pentafluoroarginine salt (LiAsF ₅ ) (Li (CF ₃ SO ₂ ) ₂ N), bis (pentafluoroethanesulfonyl) imide salt (LiN (C ₂ F ₅ SO ₂ ) ₂ ), trifluoromethanesulfonic acid salt Li (CF ₃ SO ₃ )), nonafluorobutane sulfonic acid salt (Li (C ₄ F ₉ SO ₃ )), and the like. The support salt may be used alone or in combination of two or more.

However, when a tetraphenylporphyrin derivative such as a tetraphenylporphyrin-metal complex, which is an oxygen desorbing material contained in an electrolytic solution, is used, the type of the high-electron donor axis ligand coordinated from the viewpoint of appropriately forming an oxygen complex and It is preferable to select the kind of the support salt in a very suitable combination.

For example, when LiBF ₄ or the like is contained as a supporting salt in the electrolytic solution and benzylimidazole is coexisted as a component of the axial ligand, a supporting electrolyte such as LiBF ₄ at the sixth position where oxygen is coordinated in the tetraphenylporphyrin derivative There may be occasions where the coordination bonding of oxygen is inhibited.

Therefore, from the viewpoint of forming an oxygen complex in which oxygen molecules can be coordinately bonded to the sixth position of the tetraphenylporphyrin derivative at a high binding force, the support salt is selected in consideration of the kind of the high-electron donor axis ligand desirable. When the benzylimidazole exemplified above is used as an axial ligand for a highly electron donor, preferable examples of the supporting salt include lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and lithium bis (Pentafluoroethanesulfonyl) imide (LiBETI) may be used.

This is because lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and lithium bis (pentafluoroethanesulfonyl) imide (LiBETI) have van der Waals volume It is possible to suppress inhibition of coordination of oxygen at the sixth position of the tetraphenylporphyrin derivative by the above-mentioned support salt when at least one of these components is contained in the electrolytic solution.

The above lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) or lithium bis (pentafluoroethanesulfonyl) imide (LiBETI) A tetraphenylporphyrin derivative having methylimidazole or tritylimidazole as an axial ligand component, and a tetraphenylporphyrin derivative in which a polymer having imidazole as a side chain is coordinated, may be used.

The support salt may be added in excess to the extent that the electrical properties of the present invention can be exhibited. The content of the supporting salt may be, for example, 2 to 70 parts by weight, for example, 20 to 50 parts by weight based on 100 parts by weight of the solvent.

When lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) is contained, the amount is preferably 20 to 35 parts by weight, and more preferably 25 to 35 parts by weight. In the case where lithium bis (pentafluoroethanesulfonyl) imide and LiBeTI are contained, the amount of the lithium bis (pentafluoroethanesulfonyl) imide is preferably 25 to 40 parts by weight, more preferably 30 to 40 parts by weight. And may further include other metal salts, for example, AlCl ₃ , MgCl ₂ , NaCl, KCl, NaBr, KBr, CaCl _{2 and the} like.

The electrolytic solution can be obtained by dissolving the tetraphenylporphyrin derivative and the supporting salt of the microporous coordinator in the above-mentioned high electron donor compound in a solvent or by adding an axial ligand. Addition of an axial ligand in the solvent allows the axial ligand of the electron donor to naturally coordinate at the fifth position of the tetraphenylporphyrin derivative to form the oxygen absorbing / desorbing material.

Further, a lithium ion conductive solid electrolyte membrane (not shown) may be disposed between the anode 110 and the cathode 120, if necessary. Examples of the lithium ion conductive solid electrolyte film include inorganic materials containing lithium ion conductive glass, lithium ion conductive crystals (ceramic or glass-ceramic), or mixtures thereof. In consideration of chemical stability, the lithium ion conductive solid electrolyte film 16 may be an oxide.

Further, if necessary, a separator (not shown) may be disposed between the lithium ion conductive solid electrolyte membrane and the anode 110. The separator is not limited as long as it can withstand the range of use of the lithium air battery. For example, a polymer nonwoven fabric such as a nonwoven fabric of polypropylene material or a nonwoven fabric of polyphenylene sulfide material, an olefin resin such as polyethylene or polypropylene And a combination of two or more of them may be used.

As used herein, the term "air" is not meant to be limited to atmospheric air, but may include a combination of gases containing oxygen, or pure oxygen gas. This broad definition of the term "air" can be applied to all applications, for example, air cells and the like.

As the electrochemical device, in addition to the lithium air cell exemplified above, a fuel cell using hydrogen and alcohol as fuel can be used.

As an example of the oxygen absorbing / desorbing material of the present invention, an example in which benzoimidazole is coordinated at the fifth position of tetrapyropallylphenylporphyrin-cobalt complex (CoTpivPP) will be described first. However, the present invention is not limited to the following description

<Examples>

      [Example 1]

[Synthesis of tetrapivaloylphenylporphyrine-cobalt complex (CoTpivPP)]

The synthesis of tetrapyropallylphenylporphyrin-cobalt complex (CoTpivPP) can be carried out by a known method. As an example, three steps of synthesis of H ₂ TamPP, synthesis of H ₂ TpivPP, and synthesis of CoTpivPP were carried out.

1. Synthesis of amino acid H ₂ TamPP

20.0 g (132.4 mmol) of 2-nitrobenzaldehyde and 9.2 ml (132.4 mmol) of pyrrole were dissolved in 400 ml of acetic acid, and the mixture was boiling-point-refluxed at 120 ° C for 30 minutes. After the reaction, the reaction mixture was cooled to room temperature, and 50 mL of chloroform was added thereto, followed by filtration and washing with chloroform. After drying, 3.53 g (yield 13%) of the nitrosome was obtained. After 5.0 g (6.3 mmol) of nitrosome was dissolved in 250 ml of hydrochloric acid, 19.2 g (84.9 mmol) of tin chloride dihydrate was added and the mixture was stirred at 70 캜 for 30 minutes for reduction. After completion of the reaction, the reaction mixture was sufficiently cooled, neutralized with aqueous ammonia and extracted with chloroform. After the solvent was removed, the product was recrystallized from a mixed solution of ethanol and hexane, filtered, washed with methanol and dried to obtain four kinds of atropisomers (α, α, α, α-, α, (yield: 79%) of an amino acid H ₂ TamPP consisting of?,?,? -,?,?,?,? -

2. Synthesis of free base S ₂ H ₂ TpivPP

The above-mentioned atropic isomer is in optically and thermally equilibrium state, and the α, α, α, α-isomer exhibits particularly strong adsorption to silica gel (chloroform / diethyl ether (v / v = 4/1) : α, α, α, α-, 0.04; α, α, β, β-, 0.43 ;, α, β, α, β-, 0.64 ;, α, α, α, β-, 0.77). Hereinafter, the experimental operation until the formation of the Pb free period was carried out under all light shielding conditions.

3.0 g (4.45 mmol) of the amino compound was dissolved in 150 mL of benzene, and the mixture was refluxed for 24 hours at 80 DEG C with 72 g of silica gel. The porphyrin-adsorbed silica gel was filtered and washed with chloroform to elute the α, β, α, β-, α, α, β and β-isomers and successively elute the chloroform / diethyl ether (v / v = 0.46 g (yield: 15%) of the α, α, α, β-isomer was obtained by changing the solvent to chloroform / acetone (v / v = 1/1) , and 2.34 g (yield: 78%) of the? -form were fractionated, respectively. 2.34 g (yield 78%) of the above α, α, α, α-isomer and 10.8 mL (40 equivalents, 138.8 mmol) of pyridine were dissolved in 100 mL of chloroform, and while cooling with ice, 17.1 mL (40 equivalents, 138.8 mmol ), And the mixture was reacted at 0 ° C for 1 hour and at room temperature for 12 hours. Pyridine and pyridine hydrochloride were removed by washing with a basic aqueous solution of ammonium. After washing with pure water until neutral, chloroform extraction was conducted to obtain 2.75 g (yield 78%) of free base form H ₂ TpivPP.

3. Synthesis of tetrapivaloylphenylporphyrin-cobalt complex (CoTpivPP)

In order to prevent irreversible oxidation of cobalt (II) by water and oxygen, the atmosphere was purged with nitrogen for 30 minutes or more in advance, and 3.01 mL of free base material H ₂ TpivPP 0.50 (0.5 mmol) and triethylamine And dissolved in 60 mL of chloroform. 3.50 g (40 equivalents, 20.0 mmol) of anhydrous cobalt (II) dissolved in 30 mL of methanol was added dropwise and the mixture was refluxed at 70 DEG C for 24 hours. After completion of the reaction, the unreacted cobalt (II) acetate was separated by filtration, and the concentrated filtrate was completely removed from the cobalt (II) acetate, which was purified and dissolved by a basic alumina column using chloroform as a solvent. Subsequently, the residue was fractionated by flash column chromatography (Rf value: CoTpivPP, 0.35; H ₂ TpivPP 0.25) using diethyl ether / hexane (v / v = 95/5) as a solvent to obtain tetrapyral 0.35 g of phenyl porphyrin-cobalt complex (CoTpivPP) was obtained (yield: 65%).

The synthesis of the tetrapivaloylphenylporphyrin-cobalt complex (CoTpivPP) is described in J. Am. Soc. Chem., 97, 1427 (1974).

[Production of oxygen absorbing / desorbing material]

The tetrapyropallylphenylporphyrin-cobalt complex (CoTpivPP) was dissolved in? -Butyrolactone to prepare a 5 占 테 solution of tetrapivaloylphenylporphyrin-cobalt complex (CoTpivPP). The benzylimidazole is naturally added to the tetraphenylpolypyrin-cobalt complex (CoTpivPP) solution by adding a predetermined amount of benzylimidazole as the axial ligand of the highly electron donated compound to form the tetraphenylpolypyrin-cobalt complex CoTpivPP) was obtained.

 [Examples 2 to 4]

 Instead of adding a certain amount of benzylimidazole as a coordinator ligand of a highly electron donor to the tetrapyropallyphenylporphyrin-cobalt complex (CoTpivPP) solution, imidazole, 1-methylimidazole and tritylimidazole The imidazole, 1-methylimidazole, and tritylimidazole were naturally added to the oxygen of Examples 2 to 4, which were coordinated to the fifth position of the tetraphenylpolypyrin-cobalt complex (CoTpivPP) An oxygen absorbing / desorbing material was obtained in the same manner as in Example 1, except that the absorbing / desorbing material was obtained.

[Comparative Example 1]

1. Synthesis of amino acid H ₂ TamPP

20.0 g (132.4 mmol) of 2-nitrobenzaldehyde and 9.2 ml (132.4 mmol) of pyrrole were dissolved in 400 ml of acetic acid, and the mixture was boiling-point-refluxed at 120 ° C for 30 minutes. After the reaction, the reaction mixture was cooled to room temperature, and 50 mL of chloroform was added thereto, followed by filtration and washing with chloroform. After drying, 3.53 g (yield 13%) of the nitrosome was obtained. After 5.0 g (6.3 mmol) of nitrosome was dissolved in 250 ml of hydrochloric acid, 19.2 g (84.9 mmol) of tin chloride dihydrate was added and the mixture was stirred at 70 캜 for 30 minutes for reduction. After completion of the reaction, the reaction mixture was sufficiently cooled, neutralized with aqueous ammonia and extracted with chloroform. After the solvent was removed, the product was recrystallized from a mixed solution of ethanol and hexane, filtered, washed with methanol and dried to obtain four kinds of atropisomers (α, α, α, α-, α, (yield: 79%) of an amino acid H ₂ TamPP consisting of?,?,? -,?,?,?,? -

2. Synthesis of free base S ₂ H ₂ TpivPP

The above-mentioned atropic isomer is in optically and thermally equilibrium state, and the α, α, α, α-isomer exhibits particularly strong adsorption to silica gel (chloroform / diethyl ether (v / v = 4/1) : α, α, α-, 0.04 ;, α, α, β, β-, 0.43 ;, α, β, α, β-, 0.64 ;, α, α, α, β-, 0.77). Hereinafter, the experimental operation was carried out under all light shielding conditions.

3.0 g (4.45 mmol) of the amino compound was dissolved in 150 mL of benzene, and the mixture was refluxed for 24 hours at 80 캜 with 72 g of silica gel. The porphyrin-adsorbed silica gel was filtered and washed with chloroform to elute the α, β, α, β-, α, α, β and β-isomers and successively elute the chloroform / diethyl ether (v / v = 0.46 g (yield: 15%) of the α, α, α, β-isomer was obtained by changing the solvent to chloroform / acetone (v / v = 1/1) , and 2.34 g (yield: 78%) of the? -form were fractionated, respectively. 2.34 g (yield 78%) of the α, α, α, α-isomer and 10.8 mL (40 equivalents, 138.8 mmol) of pyridine were dissolved in 100 mL of chloroform. The pyridine and pyridine hydrochloride were removed by washing with a basic aqueous solution of ammonium. After washing with pure water until neutral, chloroform extraction was performed to obtain 2.75 g (yield 78%) of free base form H ₂ TpivPP.

3. Synthesis of tetraphenylporphyrin-cobalt complex (CoTpivPP) in which the pseudorabies are not coordinated

In order to prevent irreversible oxidation of cobalt (II) by water and oxygen, the atmosphere was purged with nitrogen for 30 minutes or more in advance, and 3.01 mL of free base material H ₂ TpivPP 0.50 (0.5 mmol) and triethylamine Dissolved in 60 mL of chloroform, and 3.50 g (40 equivalents, 20.0 mmol) of anhydrous cobalt (II) dissolved in 30 mL of methanol was added dropwise and the mixture was refluxed at 70 ° C for 24 hours. After completion of the reaction, the unreacted cobalt (II) acetate was separated by filtration, and the concentrated filtrate was completely removed from the cobalt (II) acetate, which was purified and dissolved by a basic alumina column using chloroform as a solvent. Subsequently, the residue was fractionated by flash column chromatography (Rf value: CoTpivPP, 0.35; H ₂ TpivPP 0.25) using diethyl ether / hexane (v / v = 95/5) as a solvent to obtain tetraphenylporphyrin- To obtain 0.35 g of a cobalt complex (CoTpivPP) (yield: 65%).

[Evaluation of Oxygen Adsorption / desorption Ability]

The oxygen adsorbing / desorbing materials of Examples 1 to 4 and the oxygen adsorption / desorption ability of the tetraphenylporphyrin-cobalt complex (CoTpivPP) of Comparative Example 1 were evaluated by the following evaluation method of oxygen affinity.

That is, first, a 1.0 M solution in which the oxygen absorbing / desorbing materials of Examples 1 to 4 were dissolved in? -Butyrolactone was prepared. Nitrogen was supplied to the solution at 25 ° C under a temperature condition, and the UV-vis spectrum at 551 nm absorption peak was measured, and the absorbance A ₁ was obtained. Subsequently, oxygen was supplied until it became pure oxygen. Then, each UV-vis spectrum was measured at a newly generated absorption peak at 551 nm, and absorbance A ₂ was obtained. (A ₂ -A ₁ ) was used to calculate the oxygen affinity parameter p ₅₀ of Examples 1 to 4 and the oxygen affinity parameter p ₅₀ of oxygen And the binding rate was calculated.

Examples 1 to 4 oxygen adsorption-desorption material and tetraphenyl porphyrin of Comparative Example 1-an oxygen affinity parameter p ₅₀ and the oxygen-binding rate of the cobalt complex (CoTpivPP) shown in Table 1 below.

The axonist of high-electron ball women Oxygen affinity parameter
(p ₅₀ / cmHg) Oxygen binding rate
(%) Example 1 Benzylimidazole 20 91 Example 2 Imidazole 43 64 Example 3 1-methylimidazole 31 67 Example 4 Tritylimidazole 23 79 Comparative Example 1 - Can not measure Less than 10

The oxygen adsorbing / desorbing materials of Examples 1 to 4 had higher oxygen binding ratio than the tetraphenylporphyrin-cobalt complex (CoTpivPP) of Comparative Example 1. In addition, the oxygen adsorption / desorption materials of Examples 1 to 4 had an oxygen bonding ratio of 60% or more, and the tetraphenylporphyrin-cobalt complex (CoTpivPP) of Comparative Example 1 had an oxygen affinity parameter p ₅₀ It could not be measured substantially.

100: lithium air cell 10, 110: positive electrode
111: collector 112: catalyst layer
11, 120: cathode 12, 130: electrolyte
13: Axisymmetric ligand of high electron donor 14: Oxygen (O ₂ )

Claims (13)

A cathode having oxygen as a cathode active material;
A negative electrode comprising a negative electrode active material capable of intercalating and deintercalating lithium ions; And
An oxygen adsorption / desorption material having an oxygen bonding rate of 60 to 95% under pure oxygen, and an electrolytic solution containing a solvent. The electrochemical device according to claim 1, wherein the oxygen absorbing / desorbing material is a tetraphenylporphyrine derivative having a structure in which an axial ligand of a high electron donor is coordinated to a fifth position and a pivaloyl group is bonded to a sixth positional direction. The electrochemical device according to claim 1, wherein the oxygen absorbing / desorbing material is a tetraphenylporphyrine derivative capable of coordinating oxygen molecules at a sixth position.   The electrochemical device according to claim 1, wherein the oxygen adsorption / desorption material comprises a tetraphenylporphyrin-metal complex. The electrochemical device according to claim 1, wherein the oxygen adsorbing / desorbing material comprises tetrapyropallyophenylporphyrine-cobalt complex (CoTpivPP) or diisophthalimide tetraphenylporphyrine-cobalt complex (CoThthPP). The electrochemical device according to claim 2, wherein the axial ligand of the high electron donor comprises amines, imines, imidazoles, or ethers. The electrochemical device according to claim 2, wherein the axial ligand of the high electron donor comprises a nitrogen-containing organic ligand.   The electrochemical device according to claim 1, wherein the content of the oxygen absorbing / desorbing material is 0.1 to 3 parts by weight based on 100 parts by weight of the solvent.   The electrochemical device according to claim 1, wherein the solvent is a non-aqueous organic solvent.   2. The electrochemical device of claim 1, wherein the electrolyte further comprises a support salt.  The electrochemical device according to claim 10, wherein the support salt is at least one of lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) and lithium bis (pentafluoroethanesulfonyl) imide (LiBETI).   The electrochemical device according to claim 1, wherein the electrochemical device is a lithium air battery.    The electrochemical device according to claim 1, wherein the negative electrode active material is lithium metal.

Images