KR20110011158A - Electrolytes for dye-sensitized solar cell using imidazole based ionic liquid - Google Patents

Abstract

PURPOSE: An imidazole-based ionic solution is provided to improve ion conductivity of electrolyte through the control of components added in the manufacture of electrolyte and the size of a linker of the ionic solution. CONSTITUTION: A method for preparing an imidazole-based polymer or oligomer type ionic solution comprises the steps of: reacting dichloromethane and 1,6-diisocyanatohexane with aminoalkylimidazole to obtain a monomer including an NCO group at a terminal group; adding chloroform and ethylene oxide compounds to the obtained compound to obtain polyethylene glycol; adding acetonitrile and alkyl iodide to the obtained compound to obtain diimidazolium iodide polyethylene.

Description

Electrolytes for dye-sensitized solar cell using imidazole based ionic liquid

The present invention relates to a dye-sensitized solar cell electrolyte using an imidazole-based ion solution, and more particularly, to an imidazole-based polymer or oligomeric ion solution represented by Formula 1 and a dye-sensitized solar cell electrolyte comprising the same. The present invention relates to a dye-sensitized solar cell employing an electrolyte.

Dye-sensitized Solar Cells (DSSCs) are photosensitive dyes adsorbed onto mesoporous films of nanoparticles TiO ₂ as photoelectrodes and triiodide / iodide redox pairs. It consists of an electrolyte containing / iodide redox couple, and a plated counter electrode.

The triiodide / iodide redox pairs in electrolytes dissolved in organic solvents are excellent mediators for the electron regeneration process in dye-sensitized solar cells, but have the disadvantage of being unstable due to volatility and leakage.

To solve this problem, non-volatile ionic liquids, which exist as stable liquids over a wide temperature range, were used as electrolytes. The use of non-volatile ionic liquids can prevent the reduction of electrolytes due to volatilization of organic solvents, but there is still a problem that electrolytes may leak during manufacture or breakage of the battery, thus deteriorating durability and handling of solar cells. .

Accordingly, gel electrolytes have been proposed in which a polymer is chemically bonded such as crosslinking or polymerization by using a bonding functional group of a monomer or an oligomer. However, the gel electrolyte also has a high risk of remaining compounds such as side reactions or unreacted functional groups during the coupling reaction such as crosslinking or polymerization, initiators and crosslinking agents added during the crosslinking and polymerization reaction, and when remaining in the electrolyte, voltage of the solar cell or Decreases the current characteristic.

In addition, when using a matrix such as a polymer in order to convert the liquid to a gel type as the gel electrolyte, the volatility or the possibility of leakage of the conventional liquid electrolyte may be improved to some extent, but the structure is merely a simple polymer to form an irregular structure. In addition, due to the lack of adhesion to the metal oxide layer, there is a problem in that the transfer path of the battery generated from the redox pair in the electrolyte is disturbed, thereby lowering conductivity or decreasing ion conductivity, thereby reducing energy conversion efficiency.

However, studies to improve the ionic conductivity by changing the properties of the electrolyte solution is insufficient.

Accordingly, the present inventors have diligently solved the above problems, and have been trying to develop an electrolyte for a dye-sensitized solar cell having excellent ion conductivity while improving stability and durability, and thus synthesized an imidazole-based polymer or oligomeric ion solution, The present invention has been completed by manufacturing a dye-sensitized solar cell having high energy conversion efficiency by employing an electrolyte containing the ion solution.

After all, the present invention has a main object to provide a dye-sensitized solar cell electrolyte containing the imidazole-based polymer or oligomeric ion solution and the ion solution, and a dye-sensitized solar cell employing the electrolyte.

In order to achieve the above object, the present invention provides an imidazole-based polymer or oligomeric ion solution.

In the present invention, the imidazole-based polymer or oligomeric ion solution is represented by the following formula (1), the weight average molecular weight is 500 to 30,000, characterized in that the linear copolymer having a symmetrical structure.

[Formula 1]

The present invention also provides a dye-sensitized solar cell electrolyte comprising the imidazole-based polymer or oligomeric ion solution and a dye-sensitized solar cell employing the electrolyte.

Electrolyte of the present invention is a liquid electrolyte, it is possible to improve the ionic conductivity by adjusting the molecular weight of the connector of the ionic solution or the components of the electrolyte manufacturing, the dye-sensitized solar cell employing the electrolyte is more stable and durable It is characterized by an improvement.

The imidazole-based polymer or oligomeric ion solution according to the present invention has a very high viscosity or a nearly solid state at room temperature, and has a symmetrical structure, and thus has a fuel-sensitized aspect compared to other ion solutions of the same weight (molecular weight). Since the iodine ions essential to the electrolyte of the battery may be included in a relatively high concentration, and the overall molecular weight and length may be adjusted by adjusting the size of the connector of the ion solution, the electrolyte containing the ion solution may be the size of the connector or the electrolyte. It is possible to improve the ion conductivity through the control of the components and the like at the time of manufacture.

In addition, the electrolyte according to the present invention can prepare a replacement electrolyte which is added to the liquid electrolyte of the conventional fuel-sensitized solar cell or replaces the main components of the liquid electrolyte to improve its performance and function, and also directly as a liquid electrolyte. Since it can be used, it can be usefully used for manufacturing fuel-sensitized solar cells with high energy conversion efficiency.

In addition, the dye-sensitized solar cell employing the electrolyte according to the present invention can solve the problems caused by the leakage and volatilization of the electrolyte generated in the dye-sensitized solar cell using the conventional liquid electrolytic material to provide a more stable and improved dye-sensitized solar cell It is possible to manufacture.

Hereinafter, the present invention will be described in detail.

The present invention provides an imidazole-based polymer or oligomeric ionic solution.

In the present invention, the imidazole-based polymer or oligomer type ion solution is represented by the following general formula (1), iodine ion (I ^-), and 1 to 25 ethylene oxide units (to appear in the formula (I) by *) and the ethylene It is characterized by having an imidazolium structure at the terminal, including an oxide unit, a urethane and urea structure connecting the same.

[Formula 1]

In addition, the imidazole-based polymer or oligomeric ionic solution of the present invention comprises 1 to 25 oxygen atoms, 2 to 50 carbon atoms, including 1 to 25 ethylene oxide units, between urethane and urea The aliphatic chain is characterized in that it contains 1 to 15 carbon atoms, the aliphatic chain between the urethane and urea may further include oxygen, nitrogen, sulfur which is a hetero atom.

In addition, the weight average molecular weight of the imidazole-based polymer or oligomeric ion solution is 500 to 30,000, characterized in that the linear copolymer having a symmetrical structure.

When the weight average molecular weight of the ion solution is less than 500, the viscosity of the oligomer is insufficient to show the characteristics as a sufficient liquid electrolyte, and when it exceeds 30,000, the viscosity increases, rather it is not preferable because the ion conductivity is lowered.

Further, the imidazole-based polymer or a counter anion of the oligomer-type ion solution is a halogen ^{_{anion, CF 3 COO -, N (}} CF 3 SO 3) 2 -, B (CN) 4 -, PF 6 -, NCS -, BF _{^{4 -, C (CN) 3}} - are characterized, or the like.

The present invention also provides a method for preparing the imidazole-based polymer or oligomeric ion solution.

In one embodiment of the present invention, the imidazole-based polymer or oligomeric ionic solution is chemically synthesized by the method shown in Scheme 1 below.

Specifically, the present invention (1) reacting aminochloroimidazole with dichloromethane and 1,6-diisocyanatohexane (1,6-Diisocyanatohexane) to obtain a monomer containing an NCO group in the terminal group Making; (2) adding chloroform and an ethylene oxide compound to the compound obtained in step (1) to obtain diimidazolium polyethylene glycol; And (3) adding acetonitrile and alkyl iodine to the compound obtained in step (2) to obtain diimidazolium iodine polyethylene.

In the step (1), the aminoalkylimidazole is preferably an aminoalkylimidazole having 1 to 20 carbon atoms, more preferably 1- (3-aminopropyl) imidazole, and the diimi of step (2) Dazolium polyethylene glycol is preferably adjusted to the molecular weight or viscosity of the imidazole-based polymer or oligomeric ionic solution finally obtained by using diethlyene glycol or polyethylene glycol (PEG). It is preferable that the molecular weight of is 100-1000.

In addition, the imidazolium iodine salt of step (3) is preferably a mono (Mono-) or di (Di-) imidazolium iodine salt.

However, the method for preparing the imidazole polymer or oligomeric ion solution according to the present invention does not need to be particularly limited, and any method may be used as long as it is a conventional synthetic method.

In addition, there is provided a dye-sensitized solar cell electrolyte comprising an imidazole-based polymer or oligomeric ion solution prepared by the method of the present invention.

In the present invention, the electrolyte containing the imidazole-based polymer or oligomeric ionic solution is a liquid having a very high viscosity at room temperature or exists in a solid state according to the size of the linker (PEO), and has a symmetrical structure. Because of the relatively high concentration of iodine ions essential to the electrolyte of the dye-sensitized solar cell, it is characterized by the ability to control the ion conductivity by controlling the molecular weight of the connector or by adjusting the component ratio of the components in the preparation of the electrolyte.

In addition, the electrolyte containing the imidazole-based polymer or oligomeric ionic solution of the present invention can be used as an additive added to the liquid electrolyte of the conventional dye-sensitized solar cell or as a substitute for replacing the main components of the liquid electrolyte. It can also be used in the production of alternative electrolytes with improved performance and function of conventional electrolytes.

When the electrolyte according to the present invention is used as an additive or substitute for electrolyte, it is preferable to dissolve it in a solvent used in a conventional liquid electrolyte. At this time, the solvent is acetonitrile, ethylene glycol, butanol, isobutyl alcohol, isopentyl alcohol, isopropyl alcohol, ethyl ether, dioxane, tetrahydrofuran, n-butyl ether, propyl ether, isopropyl ether, acetone, methyl ethyl Ketones, methylbutyl ketone, isobutyl ketone, ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), gamma-butyrolactone (GBL) It is preferably an organic solvent selected from the group consisting of N-methyl-2-pyrrolidone, 3-methoxypropionitrile (MPN) and mixtures thereof. However, the present invention is not limited to the kind of the organic solvent. In addition, the electrolyte of the present invention with respect to the organic solvent is preferably mixed in a concentration of 0.2 ~ 0.8M the performance of the electrolyte is preferred.

In addition, when the ion solution according to the present invention is used as an additive / replacement agent for electrolytes, other additives (for example, 4-tert-butylpyridine (TBP), etc.) which are commonly used for preparing a liquid electrolyte of a dye-sensitized solar cell, or It may further include a plasticizer.

In addition, the electrolyte containing the imidazole-based polymer or oligomeric ion solution of the present invention can be used directly as a liquid electrolyte of a dye-sensitized solar cell under conditions of maintaining a liquid state at room temperature.

When the electrolyte according to the present invention is directly used as a liquid electrolyte of a dye-sensitized solar cell, an iodide salt capable of dissolving I ₂ or supplying iodine ions to the imidazole-based polymer or oligomeric ion solution of the present invention is further added. It is preferable to use.

In the present invention, the iodide salt is not particularly limited, but lithium iodide, sodium iodide, potassium iodide, magnesium iodide, copper iodide, silicon iodide, manganese iodide, barium iodide, molybdenum iodide, calcium iodide, iron iodide, iron iodide, Zinc iodide, mercury iodide, ammonium iodide, methyl iodide, methylene iodide, ethyl iodide, ethylene iodide, isopropyl iodide, isobutyl iodide, benzyl iodide, benzoyl iodide, allyl iodide, and imidazole iodide. . However, iodide salts may be used in combination with additional additives to prevent this phenomenon because in some cases they may affect the efficiency of the entire solar cell by intercalation or other interactions with TiO ₂ in the solar cell. Which is common to those skilled in the art.

The present invention also provides a dye-sensitized solar cell employing an electrolyte containing the above-mentioned imidazole-based polymer or oligomeric ion solution.

In the present invention, the electrolyte may be used as an additive added to a conventional liquid electrolyte or as a substitute for replacing the main components of the liquid electrolyte, or may be used directly as a liquid electrolyte.

Dye-sensitized solar cell employing an electrolyte according to the present invention can solve the problems caused by leakage and volatilization that can occur in the conventional liquid electrolyte, it is possible to control the ion conductivity of the electrolyte.

Hereinafter, the present invention will be described in more detail with reference to Examples.

However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited to the following examples.

Example 1 Monomer Synthesis Containing NCO Group at Terminal

A 100 ml three-necked flask was equipped with a cooler and dissolved in 10 ml of dichloromethane with 1- (3-aminopropyl) imidazole (0.97 ml, 7.9 mmol). And a solution obtained by dissolving 1,6-diisocyanatohexane (1.6-Diisocyanatohexane; 1.31 ml, 7.9 mmol) in 8 ml of dichloromethane were mixed at room temperature under nitrogen and reacted for 24 hours. After 24 hours, the reaction solution was filtered, and the filtered solid was washed with dichloromethane (yield: 95% or more).

Example  2. Diimidazolium Polyethylene glycol  100 ( Di - imidazolium  Synthesis of polyethyleneglycol 100)

A 100 mL three-necked flask was equipped with a cooler, diethyleneglycol (1.5 g, 15 mmol) was dissolved in 30 ml of chloroform (Chloroform), and the monomer (1.7 g, 60 mmol) prepared in Example 1 was prepared. It added under nitrogen conditions and made it react at 60 degreeC for 16 hours. Upon completion of the reaction, unreacted material was removed by precipitation in an ether solution (yield: 90% or more).

Example 3 Synthesis of Di-imidazolium polyethyleneglycol 200

A 100 ml three-necked flask was equipped with a cooler, and polyethylene glycol 200 (Polyethyleneglycol; 1.2 g, 6 mmol) was dissolved in 30 ml of chloroform, and the monomer (3.51 g, 12 mmol) prepared in Example 1 was dissolved under nitrogen. It was added and reacted at 60 degreeC for 16 hours. After the reaction was completed, precipitated in ether solution to remove unreacted material (yield: 90% or more).

Example 4 Synthesis of Di-imidazolium polyethyleneglycol 1000

A 100 ml three-necked flask was equipped with a cooler, and polyethylene glycol 1000 (1.5 g, 1.5 mmol) was dissolved in 30 ml of chloroform, and the monomer (1.76 g, 6 mmol) prepared in Example 1 was added under nitrogen conditions. The reaction was carried out at 60 ° C. for 16 hours. After the reaction was completed, precipitated in ether solution to remove unreacted material (yield: 90% or more).

Example 5 Synthesis of Mono imidazolium iodide salt (MII)

A 100 ml three-necked flask was equipped with a cooler, and 1 g of the monomer of Example 1 was dissolved in 20 ml of acetonitrile, and 0.35 ml of methyl iodide was added under nitrogen conditions for 12 hours at 40 ° C. Reacted. Upon completion of the reaction, unreacted material was removed by precipitation in an ether solution (yield: 90% or more).

Example  6. Diimidazolium  Iodine polyethylene 100 ( Di - imidazolium iodide  Synthesis of polyethylene 100)

A 100 ml three-necked flask was equipped with a cooler, 1 g of di-imidazolium polyethylene glycol synthesized in Example 2 was dissolved in 20 ml of acetonitrile, and 0.35 ml of methyl iodine) was added under nitrogen to 40 ° C. The reaction was carried out for 12 hours. After the reaction was completed, precipitated in ether solution to remove unreacted material (yield: 90% or more).

Example 7 Synthesis of Di-imidazolium iodide polyethylene 200

A 100 ml three-necked flask was equipped with a cooler, 1 g of di-imidazolium polyethylene glycol 200 synthesized in Example 3 was dissolved in 20 ml of acetonitrile, and 0.35 ml of methyl iodine was added under nitrogen conditions at 40 ° C. The reaction was carried out for 12 hours. After the reaction was completed, precipitated in ether solution to remove unreacted material (yield: 90% or more).

Example 8 Synthesis of Di-imidazolium iodide polyethylene 1000

A 100 ml three-necked flask was equipped with a cooler, and 1 g of di-imidazolium polyethylene glycol synthesized in Example 4 was dissolved in 20 ml of acetonitrile, and 0.35 ml of methyl iodine was added under nitrogen conditions at 40 ° C. The reaction was carried out for 12 hours. After the reaction was completed, precipitated in ether solution to remove unreacted material (yield: 90% or more).

Experimental Example 1. Confirmation of Structure

Compounds synthesized in the above Example was confirmed the structure using ¹ H NMR (Brucker Avance 400M, Brucker, Germany), the results are shown in Figures 1 and 2.

As shown in Figure 1, in the case of the monomer (NCO-Imidazole) prepared in Example 1, the hydrogen peak of the carbon double bond of the imidazole can be confirmed in the vicinity of 6.9 ~ 7.2 ppm, between the imidazole in the vicinity of 7.6 ppm The hydrogen peak of carbon in was found. However, in the case of MII prepared in Example 5, the peaks of 6.9 to 7.2 ppm and 7.6 ppm were changed to salt form by iodination, and thus, it was confirmed that the MII was shifted to the downfield by the charge change by iodine.

In Figure 2, monomer and diimidazolium polyethylene glycol (DIPEG) showed hydrogen peak of carbon double bond of imidazole at 6.9 ~ 7.2 ppm, and hydrogen peak of carbon between imidazole at 7.6 ppm. , NH peaks at 5.8-5.9 ppm. In addition, when the peak of glycol appeared in the vicinity of 4.1-4.2 ppm, and the hydrogen peak of the carbon next to the NCO of glycol appeared in the vicinity of 3.8 ppm, it was confirmed that glycol was couple | bonded with NCO.

In addition, diimidazolium iodine polyethylene (DIIPEG) also shifted downfield by positive charge / negative charge because peaks of 6.9 to 7.2 ppm and 7.6 ppm are converted into salt form by iodination. I could confirm that.

Example 9 Preparation of Electrolyte 1 Using Diimidazolium Iodine Polyethylene

In order to evaluate the function as an electrolyte when the ionic solution according to the present invention is used as an additive for an electrolyte which is added to a conventional liquid electrolyte, diimidazolium iodine polyethylene (DIIPEG) prepared in Examples 6 to 8 was dissolved in 0.1 M tetrachloric acid tetrachlorate. Each 2 mM electrolyte was prepared by dissolving in 3-methoxypyropionitrile (MPN) containing butylammonium (Tetrabutylammonium Perchlorate, TBAP).

For all solar cell (DSSC) performance measurements, commercial liquid electrolyte EL141 (Dyesol) and ionic liquid base electrolyte PMII (Solaronix SA) were used as comparative examples.

The liquid electrolyte of DSSC is obtained by dissolving iodine and 4-tert-butylpyrindine (TBP) in 3-methoxypropionitrile (MPN) as an additive using PMII and the oligomeric ionic solution electrolyte of the present invention. At this time, iodide, iodine and TBP were added at concentrations of 0.5 M, 0.05 M and 0.5 M, respectively.

Example 10 Preparation of Electrolyte 2 Using Diimidazolium Iodine Polyethylene

In order to evaluate the function as an electrolyte when the ionic solution according to the present invention is used as a substitute for an electrolyte that replaces the main components of the liquid electrolyte, the liquid electrolyte of DSSC is a diimidazolium iodine polyethylene prepared in Examples 6 to 8 ( DIIPEG) was prepared by dissolving iodine and 4-tert-butylpyrindine (TBP) in 3-methoxypropionitrile (MPN) as an additive, wherein DIIPEG, iodine and TBP It was added at concentrations of 0.25 M, 0.05 M and 0.5 M, respectively.

For all solar cell (DSSC) performance measurements, a commercial liquid electrolyte EL141 (Dyesol) consisting of organic and inorganic iodine salts and iodine in gamma-butyrolacton (GBL) was used as a comparative example.

In addition, for the electrochemical evaluation of the oligomeric ion solution of the present invention, dissolved in 3-methoxypyropionitrile (MPN) containing 0.1M Tetrabutylammonium Perchlorate (TBAP) 2 mM A liquid electrolyte was prepared.

Experimental Example 2 Analysis of Electrochemical Properties

The electrochemical reaction of the electrolyte prepared in Examples 9 and 10 and the commercial liquid electrolyte as a comparative example were measured by electrochemical cyclic voltammetry.

As a result, as shown in Figure 4, it was confirmed that both the commercial liquid electrolyte and the electrolyte according to the present invention showed the electrochemical reaction of the characteristic iodide and triiodide similarly.

Experimental Example 3. Evaluation of Functionality as an Electrolyte

Measuring the OCV (open circuit voltage, V _OC) and short circuit current (short circuit current, I _SC) of Example 9 and (for comparison) a liquid form electrolyte and a commercial liquid form electrolyte according to the present invention prepared in 10, and the photocurrent The IV curve of the voltage is shown in FIG. 5.

As a result, the liquid electrolyte according to the present invention is V _OC = 0.65 V, I _SC = 0.076 ㎃ (FF = 60.97) and V _OC = 0.73 V, I, respectively, under the same conditions when compared with a commercial liquid electrolyte (PMII manufactured by Solaronix). _{It was shown that SC} = 0.079 kPa (FF = 67.5), and it was confirmed that it could sufficiently replace the conventional liquid electrolyte of the dye-sensitized solar cell.

Experimental Example 4 Measurement of Ion Conductivity

The ionic conductivity of the liquid electrolyte and the commercial liquid electrolyte (comparative example) according to the present invention prepared in Examples 9 and 10 were measured using an electrochemical impedance method, and the results are shown in FIG. 6.

As shown in FIG. 6, the liquid electrolytes according to the present invention (DIIPEG100 and DIIPEG200) showed almost similar ionic conductivity as commercial liquid electrolytes (PMII manufactured by Solaronix).

Experimental Example 5. Evaluation of Electrolyte (3) Function Using Diimidazolium Iodine Polyethylene

In order to evaluate the function as an electrolyte when the ionic liquid according to the present invention was directly used as a liquid-free type, I was added to each of the imidazolium iodine polyethylenes (DIIPEG) prepared in Examples 6 to 8. After dissolving ₂ directly, the open circuit voltage (V _OC ) and the short circuit current (I _SC ) were measured, and the results are shown in FIG. 7.

As shown in FIG. 7, when the DIIPEG100 and the DIIPEG200 are directly used as electrolytes, the performance as the electrolytes is relatively insufficient compared to the comparative example, but it can be seen that it functions as a liquid electrolyte.

On the other hand, in the case of DIIPEG1000, the functional deterioration was remarkable, and it was confirmed that it was almost impossible to expect a function as an electrolyte. Since the experiment was conducted at room temperature, it is believed to be due to solidification and contact problems at the interface in the solar cell. Actually, when the temperature is raised to 80 ° C. or higher, the performance as an electrolyte may be remarkably improved.

The above results are characteristics commonly seen in the electrolyte of the conventional ionic solution system having a high viscosity. In the case of materials solidified at room temperature, it is apparent that the liquefaction proceeds at a high temperature and the interface contact property is remarkably improved. Furthermore, even in the case of solidification, it is well known that addition of a very small amount of liquid electrolyte greatly improves contact characteristics and overall ionic conductivity at an interface, thereby greatly improving performance as an electrolyte. Therefore, the electrolyte according to the present invention was able to sufficiently confirm the possibility of using directly as a liquid electrolyte.

In conclusion, the electrolyte according to the present invention can be added to the liquid electrolyte for conventional dye-sensitized solar cells or used as a substitute for the main components of the liquid electrolyte, and can also be used directly as a liquid electrolyte. This suggests that it is possible to develop alternative electrolytes.

As described above, specific portions of the contents of the present invention have been described in detail, and for those skilled in the art, these specific techniques are merely preferred embodiments, and the scope of the present invention is not limited thereto. Will be obvious. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

1 is a ¹ H NMR spectrum confirming the structure of the monomer (NCO-Imidazole) and mono imidazolium iodine salt (MII) containing an NCO group in the terminal group according to the present invention.

2 is a ¹ H NMR spectrum confirming the structure of the monomer (NCO-Imidazole), diimidazolium polyethylene glycol (DIPEG) and diimidazolium iodine polyethylene (DIIPEG) containing an NCO group in the terminal group according to the present invention.

Figure 3 is a graph measuring the thermal stability of diimidazolium iodine polyethylene (DIIPEG) according to the present invention using a thermogravimetric analysis (TGA).

Figure 4 is a graph comparing the electrochemical characteristics of the electrolyte and the conventional liquid electrolyte (PMII) according to an embodiment of the present invention.

FIG. 5 is a graph showing a correlation curve (IV curve) between photocurrent-photovoltage of an electrolyte and a conventional liquid electrolyte (PMII) according to an embodiment of the present invention.

6 is a graph illustrating changes in ion conductivity of an electrolyte and conventional liquid electrolytes (Dyesol EL141 and PMII) according to an embodiment of the present invention.

7 is a graph showing a correlation curve (IV curve) of photocurrent-photovoltage of an electrolyte according to another exemplary embodiment of the present invention.

Claims (20)

An imidazole-based polymer or oligomeric ionic solution represented by the following formula (1). [Formula 1]

The method of claim 1, The ionic solution includes iodine ions (I ⁻ ), 1 to 25 ethylene oxide units (denoted by * in Formula 1), and the ethylene oxide units and urethane and urea structures connecting them to imidazolium at the end. An imidazole-based polymer or oligomeric ionic solution, characterized in that the structure. 3. The method of claim 2, Ethylene oxide unit of the ionic solution is an imidazole-based polymer or oligomeric ionic solution, characterized in that it comprises 1 to 25 oxygen atoms, 2 to 50 carbon atoms. 3. The method of claim 2, The aliphatic chain between the urethane and urea of the ionic solution is an imidazole-based polymer or oligomeric ionic solution, characterized in that it contains 1 to 15 carbon atoms. The method of claim 4, wherein The aliphatic chain between the urethane and urea of the ionic solution is an imidazole-based polymer or oligomeric ionic solution, characterized in that it further comprises a hetero atom oxygen, nitrogen, sulfur. The method of claim 1, The ion solution is an imidazole-based polymer or oligomeric ion solution, characterized in that the weight average molecular weight of 500 to 30,000. The method of claim 1, The ionic solution is an imidazole-based polymer or oligomeric ionic solution, characterized in that the linear copolymer having a symmetrical structure. The method of claim 1, The ion solution may be a counter anion, halogen anion, CF ₃ COO ⁻ , N (CF ₃ SO ₃ ) ₂ ⁻ , B (CN) ₄ ⁻ , PF ₆ ⁻ , NCS ⁻ , BF ₄ ⁻ , or C (CN) ₃ ⁻ Imidazole-based polymer or oligomeric ion solution, characterized in that it comprises a. (1) reacting an aminoalkylimidazole with dichloromethane and 1,6-diisocyanatohexane to obtain a monomer containing an NCO group at the terminal; (2) adding chloroform and an ethylene oxide compound to the compound obtained in step (1) to obtain diimidazolium polyethylene glycol; And (3) adding acetonitrile and alkyl iodine to the compound obtained in step (2) to obtain diimidazolium iodine polyethylene; the imidazole-based polymer type or oligomer type of claim 1 Method for preparing an ion solution. The method of claim 9, In the step (1), the aminoalkylimidazole is a method for producing an imidazole-based polymer or oligomeric ionic solution, characterized in that the aminoalkylimidazole having 1 to 20 carbon atoms. The method of claim 9, Diimidazolium polyethylene glycol of step (2) is the molecular weight or viscosity of the imidazole-based polymer or oligomeric ionic solution finally obtained using diethylene glycol (Diethlyene glycol) or polyethylene glycol (PEG) Method for producing an imidazole-based polymer or oligomeric ionic solution, characterized in that the control. The method of claim 9, Method for producing an imidazole-based polymer or oligomeric ionic solution, characterized in that the imidazolium iodine salt of step (3) is a mono (Mono-) or di (Di-) imidazolium iodine salt. An electrolyte for dye-sensitized solar cells comprising the imidazole polymer-type or oligomer-type ion solution of any one of claims 1 to 8. The method of claim 13, The electrolyte is a dye-sensitized solar cell electrolyte, characterized in that used as an additive to add to the liquid electrolyte of the dye-sensitized solar cell or as a substitute for replacing the main components of the liquid electrolyte. 15. The method of claim 14, The electrolyte is acetonitrile, ethylene glycol, butanol, isobutyl alcohol, isopentyl alcohol, isopropyl alcohol, ethyl ether, dioxane, tetrahydrofuran, n-butyl ether, propyl ether, isopropyl ether, acetone, methyl ethyl ketone , Methylbutyl ketone, isobutyl ketone, ethylene carbonate (EC), diethyl carbonate (DEC), propylene carbonate (PC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), gamma-butyrolactone (GBL), An electrolyte for dye-sensitized solar cells, further comprising an organic solvent selected from the group consisting of N-methyl-2-pyrrolidone, 3-methoxypropionitrile (MPN) and mixtures thereof. The method of claim 15, The electrolyte is a dye-sensitized solar cell electrolyte, characterized in that mixed in a concentration of 0.2 ~ 0.8M with respect to the organic solvent. The method of claim 13, The electrolyte is a dye-sensitized solar cell electrolyte, characterized in that used directly as a liquid electrolyte of the dye-sensitized solar cell. The method of claim 17, The electrolyte is a dye-sensitized solar cell electrolyte, characterized in that it further adds an iodide salt capable of supplying I ₂ or iodine ions. The method of claim 18, The iodide salts include lithium iodide, sodium iodide, potassium iodide, magnesium iodide, copper iodide, silicon iodide, manganese iodide, barium iodide, molybdenum iodide, calcium iodide, iron iodide, ammonium iodide, silver iodide, silver iodide, silver iodide, silver iodide An electrolyte for dye-sensitized solar cells, which is selected from the group consisting of methyl iodide, methylene iodide, ethyl iodide, ethylene iodide, isopropyl iodide, isobutyl iodide, benzyl iodide, benzoyl iodide, allyl iodide, and imidazolium iodide. A dye-sensitized solar cell employing an electrolyte containing the imidazole-based polymer or oligomer ion solution according to any one of claims 13 to 19.

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