KR102270252B1 - Nucleic acid based solid state single ion conductor, electrolyte having the same, and lithium ion cell having the same - Google Patents

Abstract

A nucleic acid-based solid-state single-ion conductor, an electrolyte including the same, and a battery including the same are provided. A nucleic acid-based solid-phase monoionic conductor comprises a nucleic acid complex consisting of at least 3 to 8 nucleic acid units and a central cation disposed at the center of the nucleic acid complex.

Description

Nucleic acid-based solid-state single ion conductor, electrolyte including same, and lithium ion battery comprising same

The present disclosure relates to a nucleic acid-based solid-state single ion conductor, a method for preparing the same, an electrolyte including the same, and a lithium ion battery including the same.

Recently, miniaturization and weight reduction of electronic products, electronic devices, communication devices, etc. is rapidly progressing, and as the need for electric vehicles is greatly raised in relation to environmental problems, the demand for performance improvement of secondary batteries used as power sources for these products also increases. the situation is. Among them, lithium ion batteries are receiving considerable attention as high-performance batteries because of their high energy density and high standard electrode potential.

A lithium ion battery using a liquid electrolyte made of a flammable organic solvent expands when overheated or overcharged, and there is a potential risk of ignition and explosion. In order to enhance the stability of devices or systems using lithium secondary batteries, such as ICT devices, electric vehicles, and energy storage systems (ESS), new electrolyte technology that does not lead to ignition or explosion is required.

Since performance degradation is caused by side reactions and polarization between the electrode active material and the liquid electrolyte interface, a method for preventing these performance degradation is required.

The present disclosure seeks to provide a nucleic acid-based solid phase monoionic conductor.

An object of the present disclosure is to provide a solid electrolyte comprising a nucleic acid-based solid-phase monoion conductor.

An object of the present disclosure is to provide a lithium ion battery including a solid electrolyte including a nucleic acid-based solid phase single ion conductor.

A nucleic acid-based solid-phase monoionic conductor according to embodiments includes a nucleic acid complex consisting of at least 3 to 8 nucleic acid units and a central cation disposed at the center of the nucleic acid complex.

Electrolytes according to embodiments include a nucleic acid-based solid-state monoion conductor.

The electrolyte according to the embodiments may further include any one selected from a liquid electrolyte, a polymer electrolyte, and an inorganic electrolyte.

Lithium ion batteries according to embodiments include an electrolyte including a nucleic acid-based solid-state single-ion conductor.

Since the electrolyte including the nucleic acid-based solid-state monoion conductor according to the embodiments does not use an organic solvent, the risk of ignition and explosion is low.

Since the nucleic acid-based solid-state single-ion conductor according to the embodiments has a single-ion conduction characteristic, it is possible to prevent performance degradation due to side reactions and polarization between the conventional electrode active material and the liquid electrolyte interface.

1 is a schematic diagram of a nucleic acid-based solid-phase monoion conductor according to embodiments.
2 shows complexes according to the types of nucleic acid units.
3 shows various cases in which the substituents of guanine are changed.
4 is a WAXS (Wide Angle X-ray Scattering) pattern of each of the lithium single ion conductors (R1_Li, Q1_Li, Y1_Li, Y2_Li) composed of the molecularly modified guanines (R1, Q1, Y1, Y2) shown in FIG. indicates.
5 is a schematic diagram showing that the attraction between the central cation and the ion channel can be adjusted when _{R 3 is modified.}
6 is a synthetic schematic diagram for explaining the molecular modification of the guanine unit for structural stabilization.
7 is a schematic diagram illustrating molecular modification of a guanine unit to improve ionic conductivity properties by controlling PES.
8 is a schematic diagram for explaining a method for preparing a nucleic acid-based solid-phase monoion conductor.
9 is a schematic diagram of an all-solid-state lithium ion battery including an electrolyte layer made of a nucleic acid-based solid-state single-ion conductor according to embodiments.
10 illustrates a case in which a protective film for a negative electrode of a metal battery is formed with a nucleic acid-based solid-state conductor according to embodiments.
11 and 12 show the results of measuring the cation transport coefficient and Arrhenius plot of the molecularly modified guanine (Y2)-based lithium single ion conductor represented by Chemical Formula 3, respectively.
13 and 14 show a lithium single ion conductor (AQ1_Li) made of molecularly modified guanine (AQ1) represented by Formula 4 and a lithium single ion conductor (Q1_Li) made of molecularly modified guanine (Q1) represented by Formula 5, respectively. Each WAXS (Wide Angle X-ray Scattering) pattern and ion conductivity (Nyquist plot) measurement results are shown.

Hereinafter, embodiments will be described in detail so that those of ordinary skill in the art can easily implement it. The embodiment may be implemented in various different forms, and is not limited to the specific embodiment described herein.

Referring to FIG. 1 , a nucleic acid-based solid-state single ion conductor 1 according to embodiments is an aggregate of a plurality of ion channels 10 . The ion channel 10 may be formed of a 1D tubular ion channel. The ion channel 10 may be formed by stacking a macrocycle 40 composed of a nucleic acid unit 20 and a central cation 30 .

The nucleic acid unit 20 may bind to the central cation 30 through electrostatic attraction.

The charge of the central cation 30 may be +1 to +3. As the central cation used, Li+, Na+, K+, Mg++, Zn++, Al+++, and the like may be used.

The nucleic acid unit 20 may include a core building block 22 and a peripheral building block 24 . The core building block 22 and the peripheral building block 24 may include a substituent for structural stabilization and a substituent for improving ion conductivity.

As the nucleic acid unit, a purine-based nucleic acid, a substituted purine-based nucleic acid, a pyrimidine-based nucleic acid, a substituted pyrimidine-based nucleic acid, a derivative molecule thereof, or the like can be used.

Adenine, guanine, etc. may be used as a purine-based nucleic acid.

As the pyrimidine-based nucleic acid, cytosine, thymine, uracil, and the like may be used.

As the purine-based nucleic acid derivative molecule, xanthine, caffeine, uric acid, and the like may be used.

Nucleic acid units 20 may form a complex (eg, triplex, quadruplex, quintuplex, sextuplex, sevenfold, octuplicate) by gathering 3 to 8 according to the type.

2 exemplifies various complexes according to the type of the nucleic acid unit 20 .

2, a guanine quadruplex and an isoguanine _{pentamer (isoG 5} -pentamer) are exemplified as an example of the complex.

Formula 1 represents guanine or a derivative thereof as an example of the nucleic acid unit 20.

[Formula 1]

In the above formula, R1 is any one selected from the group consisting of H, F, and the following formula,

Ar is any one selected from the group consisting of the following formula,

X is O, S, Se or Te;

n is 1 to 3,

, 또는

이고, A is C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego,

p is 0 to 24, m is 1 to 12, k is 0 to 8,

,

, 및 하기 화학식으로 표시되는 그룹에서 선택된 어느 하나이고, In the above formula, R ₂ is H, C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

,

, and any one selected from the group represented by the following formula,

,

,

, 또는

이고, A is C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego,

p is 0 to 24, m is 1 to 12, k is 0 to 8,

Wherein R ₃ is NH ₂ or NHCOR,

, 또는

이고R is CH ₃ , CF ₃ , benzene, C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego

p is 0 to 24, m is 1 to 12, and k is 0 to 8.

Formula 2 represents a guanine derivative capable of stacking by π-π interaction.

[Formula 2]

,

, 및 하기 화학식으로 표시되는 그룹에서 선택된 어느 하나이고, In the above formula, R ₂ is H, C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

,

, and any one selected from the group represented by the following formula,

,

,

, 또는

이고, A is C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego,

p is 0 to 24, m is 1 to 12, k is 0 to 8,

Wherein R ₃ is NH ₂ or NHCOR,

, 또는

이고R is CH ₃ , CF ₃ , benzene, C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego

p is 0 to 24, m is 1 to 12, k is 0 to 8,

In the above formula, Ac is any one selected from the following formulas.

,

,

Formula 3 represents xanthan or a derivative thereof as another example of the nucleic acid unit 20.

[Formula 3]

In the above formula, R1 is any one selected from the group consisting of H, F, and the following formula,

Ar is any one selected from the group consisting of the following formula,

X is O, S, Se or Te;

n is 1 to 3,

, 또는

이고, A is C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego,

p is 0 to 24, m is 1 to 12, k is 0 to 8,

,

, 및 하기 화학식으로 표시되는 그룹에서 선택된 어느 하나이고, In the above formula, R ₂ is H, C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

,

, and any one selected from the group represented by the following formula,

,

,

, 또는

이고, A is C _p H _2p+1 , C _p H _2p , C _m F _2m+1 ,

, or

ego,

p is 0 to 24, m is 1 to 12, and k is 0 to 8.

3 illustrates various examples (R1, Q1, Y1, Y2) of guanine formed by changing _{R 1} and/or R _{2 .}

When the guanine shown in FIG. 3 is applied, the structural stability of the ion channel 10 made of a guanine quadruplex can be improved. Specifically, in FIG. 4, each of the lithium single ion conductors (R1_Li, Q1_Li, Y1_Li, Y2_Li) composed of the molecularly modified guanines (R1, Q1, Y1, Y2) shown in FIG. 3 is WAXS (Wide Angle X-ray Scattering) The pattern is shown. In FIG. 4, the pattern (d ₍₁₀₀₎ , d ₍₁₁₀₎ , d _{(210) ) corresponding to the hexagonal columnar structure and the pattern (d (001)} ) corresponding to the stacked structure of the π-π interaction are can be seen to appear. Accordingly, it can be confirmed that each of the lithium single ion conductors (R1_Li, Q1_Li, Y1_Li, Y2_Li) achieves structural stability through molecular modification in which _{R 1} and/or R _{2 are different.}

5 is a schematic diagram showing that the attraction between the central cation 30 and the ion channel 10 can be adjusted when _{R 3 is modified.}

Hereinafter, controlling the attractive force between the central cation 30 and the ion channel 10 through the unit structure modification is referred to as a potential energy surface (PES) control.

As illustrated in FIG. 5 , ^{it can be seen that the electrostatic potential (Ha/e −} ) of the guanine quadruplex can be controlled in the range of -0.11162 to -0.10481 through structural modification of the guanine unit. Of course, the numerical range of FIG. 5 is exemplary, and these values can be controlled to be lower through modification of the substituent.

It can be seen from the results of FIG. 5 that the ion migration barrier can be lowered through the potential energy surface control. Therefore, the ionic conductivity of the solid-state ion conductor 1 can be realized beyond the ionic conductivity of the existing solid-state ion conductor. For example, the ionic conductivity may be controlled to be ^{10 -10} to 10 ^{-2 S/cm.}

6 is a synthetic schematic diagram for explaining the molecular modification of the guanine unit for structural stabilization.

In FIG. 6, a method for preparing guanine substituted with 3,4,5-tridodecyl-benzyl-ethyl (tridodecyloxy-benzyl-ethyl) group will be described as an example.

First, ethyl-3,4,5-trihydroxy-benzoate (ethyl-3,4,5-trihydroxy-benzoate) was reacted with bromodecane, and then sequentially reacted with LiAlH4 and PBr3 to 3,4 After forming ,5-tridodecyl-benzyl-ethyl bromide, it is reacted with guanine to form guanine substituted with 3,4,5-tridodecyl-benzyl-ethyl group.

The thus formed substituted guanine can achieve structural stability due to the 3,4,5-tridodecyl-benzyl-ethyl group.

7 is a schematic diagram illustrating molecular modification of a guanine unit to improve ionic conductivity properties by controlling PES.

7 is 3,4,5-tree, R ₂ dodecyl-ethyl group and the described method of manufacturing the unit guanine acetyl group is substituted by R _3-benzyl.

First, guanine is substituted with an acetyl group, and then reacted with 3,4,5-tridodecyl-benzyl-ethyl bromide to prepare PES-controlled guanine units (Acetyl Q1, AQ1).

8 is a schematic diagram for explaining a method of manufacturing a nucleic acid-based solid-phase single-ion conductor (1).

First, a solution in which the nucleic acid unit 20 and the salt containing the central cation 30 are mixed in a predetermined molar ratio is prepared.

8 illustrates a guanine nucleic acid unit (AQ1) in which an acetyl group is substituted with a nucleic acid unit 20 to achieve PES control, and a 3,4,5-tridodecyl-benzyl-ethyl group is substituted to achieve structural stabilization, and a central cation ( 30) exemplifies lithium ions, but these may be changed to various nucleic acid units and central cations.

When the nucleic acid unit 20 is molecularly modified guanine and the central cation 30 is lithium ion, a solution mixed in a molar ratio of 4:1 may be used. In this case, as the solvent, THF, CHCl ₃ , acetone, etc. may be used.

In the mixed solution, the nucleic acid unit 20 and the central cation 30 are combined by electrostatic attraction (eg, hydrogen bonding) to form the macrocycle 40 .

Then, macrocycles (eg, guanine metabolites) are stacked in a π-π interaction to form an ion channel 10 .

In general, in the case of a nucleic acid-based quadruplex, the maximum is that about 4 to 5 macrocycles are stacked, whereas in the ion channel 10 according to embodiments, 10 or more and at most tens of macrocycles are stacked and crystallinity is improved.

The reason is that a nucleic acid-based quadruplex was synthesized as a solid phase. Most of the observation reports of nucleic acid-based quadrules were conducted in the liquid phase, and in the liquid phase, the size of the central cation and the solvation energy affect the stability of the quadruple.

The synthesis of the solid-phase quadruplex according to the embodiments may exclude the solvation energy of the central ion, so that the quadruplex is formed using Li+ having a high unit charge density as the central ion.

In addition, K+ has a large ion size and is positioned between two quadruples, whereas Li+ has a small size and is positioned between one quadruple. Accordingly, the Li+-based quadruplex has relatively high stacking stability.

In order to ensure sufficient self-assembly time, an extraction solvent (acetone, ethyl ether, etc.) is injected into the mixed solution at a sufficiently low rate, and then the precipitated assembly is washed/dried to obtain a nucleic acid-based solid-phase single-ion conductor (1). .

The ion channels 10 are vertically oriented by various vertical alignment methods to finally form a nucleic acid-based solid-phase single ion conductor 1 .

The vertical orientation method is described in J. Am. Chem. Soc. 2006, 128,5574 or ACS Nano 2014, 8,11977. The method disclosed in et al. can be applied.

The nucleic acid-based solid-state single ion conductor 1 according to embodiments may have an activation energy of about 0.13 eV. This is significantly lower than that of the conventional inorganic electrolyte. And, since the nucleic acid-based solid-phase single ion conductor 1 according to the embodiments is a conductor that selectively moves only cations, it may exhibit an excellent cation transference number. Specifically, the cation transport coefficient (t _Li ⁺ ) may represent about 0.7 to 0.99.

9 is a schematic diagram of an all solid state lithium ion cell including an electrolyte layer 11 made of a nucleic acid-based solid state single ion conductor 1 according to embodiments.

In the all-solid-state lithium ion battery, the anode 2 and the cathode 4 are in contact on both sides of the electrolyte layer 11 made of the nucleic acid-based solid-state single ion conductor 1, respectively, and the anode current collector 3 is located on the outside of the anode 2 ) is the cathode current collector 5 is in contact with the outside of the cathode (4). During charging, electrons (e-) are supplied to the anode 2 side, and lithium ions (Li+) are accumulated in the anode 2 . On the other hand, during discharge, lithium ions (Li+) accumulated in the anode 2 return to the cathode 4 side, and electrons are supplied to the operation site 6 .

The thickness of the electrolyte layer 11 comprising the nucleic acid-based solid-state single ion conductor 1 is not particularly limited, but it is preferably as thin as possible to prevent a short circuit between the anode 2 and the cathode 4 . Specifically, it is preferable that it is 1-1000 micrometers, and it is more preferable that it is <200 micrometers.

In addition, the anode current collector (3), the anode (2), the electrolyte layer 11 including the nucleic acid-based solid-state single ion conductor (1), the cathode (4), between each layer of the cathode current collector (5) or You may interpose or arrange|position a functional layer, a member, etc. suitably on the outer side. In addition, each layer may be comprised by a single layer, and may be comprised by multiple layers.

If necessary, the electrolyte layer 11 may be configured in a complex form of an existing electrolyte and a nucleic acid-based solid-state monoion conductor according to embodiments. For example, liquid electrolyte (1M LiPF6 in EC/DEC=1/1 (v/v), 1M LiTFSI in DOL/DME=1/1 (v/v), etc.), polymer electrolyte (PEO w/ Li salt, lithiated nafion, etc.), inorganic electrolytes (LLZO, LGPS, etc.) and a nucleic acid-based solid-phase single-ion conductor are combined to form the electrolyte layer 11, so that the advantages of each electrolyte can be used in a complex way.

10 illustrates a case in which the protective film 111 for the negative electrode 100 of a metal battery is formed with the nucleic acid-based solid-state conductor 1 according to the embodiments.

Metal battery negative electrodes, such as lithium metal negative electrodes, are known to cause problems such as increased surface resistance layer due to electrode/electrolyte interface side reactions, electrolyte and lithium depletion, dendrite formation due to non-uniform lithium electrodeposition and elution, and short circuit inside the battery. have.

When the protective film 111 made of the nucleic acid-based solid-state conductor 1 according to the embodiments is formed on the metal battery negative electrode 100 (eg, lithium metal negative electrode) as illustrated in FIG. 10 , as described above Since the same irreversible problem does not occur, the lifespan characteristics of the lithium metal battery negative electrode can be improved.

Hereinafter, preferred experimental examples are presented to help the understanding of the present invention, but the following experimental examples are merely illustrative of the present invention, and the scope of the present invention is not limited to the following examples.

Experimental Example 1

Preparation of guanine quadruple-based solid-phase monoionic conductors

A tetrahydrofuran solution was prepared in which molecularly modified guanine (Y2) represented by the following Chemical Formula 4 and a lithium salt were mixed in a molar ratio of 4:1. In order to secure sufficient time for self-assembly of the nucleic acid molecules in the mixed solution, an extraction solvent (acetone) was injected in a gaseous state. Then, the precipitated assembly was washed/dried to prepare a molecularly modified guanine (Y2)-based lithium single ion conductor (Y2_Li) represented by Chemical Formula 4 (4).

[Formula 4]

Confirmation of self-assembly of molecularly modified guanine (Y2)-based lithium single ion conductor (Y2_Li) represented by Formula 4

The result of forming a solid sheet having a diameter of about 1 cm with the prepared material (Y2_Li) is shown on the left side of FIG. 11 , and the result of XRD measurement on the solid sheet is shown on the right side of FIG. 11 . From the XRD measurement data, the pattern corresponding to the hexagonal columnar structure (d ₍₁₀₀₎ , d ₍₁₁₀₎ , d ₍₂₁₀₎ ) and the pattern corresponding to the stacked structure of the π-π interaction (d ₍₀₀₁₎ ) You can see that this appears. Through this, it can be confirmed that a self-aligned single ion conductor is formed.

Measurement of cation transport coefficient and Arrhenius plot of molecularly modified guanine (Y2)-based lithium monoion conductor (Y2_Li) represented by Formula 4

The left side of FIG. 12 shows the result of Arrhenius float measurement and the right side shows the activation energy of the conventional electrolyte. From the measurement results, it can be seen that the molecularly modified guanine (Y2)-based lithium single ion conductor (Y2_Li) represented by Chemical Formula 4 exhibits an activation energy of 0.13 eV. From this, it can be seen that the activation energy can be significantly lowered compared to the conventional electrolyte.

Experimental Example 2

PES Controlled Guanine Quadruple-Based Solid Phase Monoionic Conductor Fabrication

Experimental Example A lithium single ion conductor (AQ1-Li) consisting of molecularly modified guanine (AQ1) represented by the following Chemical Formula 5 and a lithium single ion conductor (Q1_Li) consisting of a molecularly modified guanine (Q1) represented by the following Chemical Formula 6 were tested. It was prepared in the same manner as in 1.

[Formula 5]

[Formula 6]

Measurement of WAXS pattern and ionic conductivity of monoionic conductors

WAXS (Wide Angle X) of a lithium single ion conductor (AQ1_Li) composed of a molecularly modified guanine (AQ1) represented by Formula 4 and a lithium single ion conductor (Q1_Li) composed of a molecularly modified guanine (Q1) represented by Formula 5 -ray scattering) pattern is shown in FIG. 13 and ion conductivity (Nyquist plot) is shown in FIG. 14 .

It can be seen from the results of FIG. 13 that Q1_Li and AQ1_Li have a similar hexagonal columnar structure. From the results of FIG. 14 , it can be seen that in the case of AQ1 subjected to PES control, the ionic conductivity is ^{improved to 10 −5 S/cm.} This is interpreted because the interaction between lithium ions (Li+) and quadruplex molecules in AQ1_Li is lower than that of Q1_Li. That is, it can be confirmed that the ionic conductivity can be improved through the PES control.

Although various embodiments have been described above, the scope of the rights is not limited thereto. The implemented form can be implemented with various modifications within the scope of the detailed description and accompanying drawings of the invention, and it is natural that this also falls within the scope of the right.

Claims (14)

a nucleic acid complex consisting of at least 3 to 8 nucleic acid units; and
A nucleic acid-based solid-state monoionic conductor comprising a central cation disposed at the center of the nucleic acid complex. According to claim 1,
The nucleic acid unit is a nucleic acid-based solid-state single ion conductor which is a purine-based nucleic acid, a substituted purine-based nucleic acid, a pyrimidine-based nucleic acid, a substituted pyrimidine-based nucleic acid, or a derivative molecule thereof. According to claim 1,
The nucleic acid unit is a purine-based nucleic acid, a substituted purine-based nucleic acid, or a nucleic acid-based solid-state single-ion conductor that is a derivative molecule thereof. According to claim 1,
The cation is Li+, Na+, K+, Mg++, Zn++, or Al+++. According to claim 1,
The nucleic acid-based solid-phase monoion conductor is
A nucleic acid-based solid-state single ion conductor formed by integrating a plurality of ion channels formed by stacking the macrocycle to which the nucleic acid complex and the central cation are bound. 6. The method of claim 5,
The plurality of ion channels is a nucleic acid-based solid-state single ion conductor in which the plurality of ion channels are vertically oriented. The method of claim 1,
The nucleic acid-based solid-phase single-ion conductor has an ionic conductivity of 10 ^-6 to 10 ^-3 S/cm. The method of claim 1,
A cation transport coefficient of the nucleic acid-based solid-phase monoionic conductor is 0.8 or more. An electrolyte comprising a nucleic acid-based solid-state monoion conductor according to any one of claims 1 to 8. 10. The electrolyte of claim 9, wherein the electrolyte further comprises any one selected from the group consisting of a liquid electrolyte, a polymer electrolyte, and an inorganic electrolyte. A lithium ion battery comprising the electrolyte according to claim 9 . 12. The method of claim 11,
The electrolyte is a lithium ion battery further comprising any one selected from the group consisting of a liquid electrolyte, a polymer electrolyte, and an inorganic electrolyte. A protective film for a metal battery negative electrode comprising a nucleic acid-based solid-state single ion conductor according to any one of claims 1 to 8. A metal battery comprising the protective film according to claim 13 .

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