KR101139923B1 - Multi-layered dyes-sensitized solar cells and method for preparing the same - Google Patents

Abstract

The present invention relates to a dye-sensitized solar cell having a multi-layered dye structure in a single cell and a method of manufacturing the same. More specifically, the present invention provides a photoelectrode comprising at least two or more dye layers having different wavelengths on a transparent conductive substrate, a counter electrode including a platinum layer disposed opposite to the photoelectrode and formed on a transparent conductive substrate; It provides a dye-sensitized solar cell comprising an electrolyte filling between the photoelectrode and the counter electrode and a manufacturing method thereof.
The dye-sensitized solar cell of the present invention has the advantage of absorbing a wide range of sunlight by forming a multilayer of dyes having different light absorption wavelengths in a single cell without connecting multiple cells. In addition, it is possible to apply a nano oxide for each dye, it is possible to implement a dye-sensitized solar cell having a high energy conversion efficiency.

Description

Multi-Layer Dye-Sensitized Solar Cell and Manufacturing Method {MULTI-LAYERED DYES-SENSITIZED SOLAR CELLS AND METHOD FOR PREPARING THE SAME}

The present invention relates to a dye-sensitized solar cell and a manufacturing method thereof, and more particularly, to a metal oxide nanoparticle layer having a multilayer dye layer in which two or more different dyes are vertically stacked by using a viscous dye desorption solution; It relates to a dye-sensitized solar cell and a method for manufacturing the same comprising a metal oxide nanooxide nanoparticle layer of different types formed on the dye layer.

A dye-sensitized photovoltaic cell is represented by a photoelectrochemical solar cell published by Gratzel et al. In Switzerland in 1991, and shows a general structure in FIG. 1A. The dye-sensitized solar cell is generally composed of a transparent conductive substrate 10, a light absorption layer 30, a counter electrode 70, and an electrolyte 40, of which the light absorption layer has a wide bandgap energy. Metal oxide nanoparticles and photosensitive dyes are adsorbed and used, and a counter electrode is used by coating platinum (Pt) 60 on the transparent conductive substrate 10.

In the dye-sensitized solar cell, when the sunlight is incident, the photosensitive dye absorbing the sunlight is in an excited state to send electrons to the conduction band of the metal oxide. The conducted electrons move to the electrode and flow to the external circuit to transfer the electric energy, and as low as the electric energy is transferred, the electrons move to the counter electrode. Thereafter, the photosensitive dye is supplied with electrons from the electrolyte solution 40 as much as the number of electrons transferred to the metal oxide, and returns to its original state. In this case, the electrolyte used receives the electrons from the counter electrode by a redox reaction and the photosensitive dye. It serves to convey.

In order to absorb light in a wide range of wavelengths, a single dye having a wide absorption wavelength range is developed or two or more nanoparticle layers are stacked to adsorb dyes having different absorption wavelengths. In particular, since the latter has the advantage of absorbing light in a wide range of wavelengths, as shown in Figure 3, it is possible to control the absorption wavelength range of the dye-sensitized solar cell using a dye having a variety of absorption wavelengths previously developed, Furthermore, it is expected that it can make a big contribution to improving efficiency. However, the metal oxide nanoparticle layer must undergo a high temperature sintering process in order to enable electron transfer. Since the dye is easily destroyed at a high temperature, once the dye adsorption process is performed, the additional metal oxide nanoparticle layer cannot be sintered. For this reason, until now, almost all dye-sensitized solar cells use only one type of dye or simply mix two or more dyes. In addition, as shown in FIG. 1B, two or more individual cells including dyes absorbing light in different wavelength ranges are stacked to increase efficiency. However, the method has a problem in that two conductive substrates are placed between the light absorbing layers, which not only impairs transparency, which is an advantage of the dye-sensitized battery, but also reduces the amount of light reaching the rear light absorbing layer. In addition, such a structure is hardly considered to be the efficiency of a single cell in that two individual cells are stacked.

In addition, in order to solve this problem, the applicant has developed a technique for stacking dyes absorbing light in different wavelength regions, such as Korean Patent Publication No. 2009-91870, so that a dye-sensitized solar cell absorbs light in a wide range of wavelength regions. To generate a high photocurrent. However, the method includes a process of reducing the photoelectric characteristics of the solar cell, such as a polymer formation-removal process to prevent pores in the lamination process and a process using an aqueous solution, thereby realizing a highly efficient dye-sensitized solar cell which is the ultimate purpose. There is a difficulty.

In order to solve the problems of the prior art, an object of the present invention is to simplify the desorption process of the dye while showing high efficiency, and to eliminate the process of removing the polymer, which can simplify the whole process of the multi-layered dye-sensitized solar cell To provide a manufacturing method.

Still another object of the present invention is to provide a highly efficient dye-sensitized solar cell which absorbs light evenly in a wide wavelength region manufactured by the method of manufacturing the dye-sensitized solar cell and has excellent photoelectric characteristics.

In order to achieve the above object, the present invention

Forming a metal oxide nanoparticle layer and a light scattering layer on one surface of the transparent conductive substrate on which the blocking layer is formed, and then performing titanium tetrachloride (TiCl ₄ ) treatment;

Adsorbing a primary dye on the metal oxide nanoparticle layer formed on the transparent conductive substrate;

Desorbing only the primary dye of the portion located above in the metal oxide nanoparticle layer to which the primary dye is adsorbed using a viscous basic desorbent;

Adsorbing a secondary dye having a different wavelength from the primary dye to the desorption site to prepare a metal oxide nanoparticle layer having a dye layer having a stacked structure having a different wavelength and a photoelectrode having a light scattering layer thereon;

Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And

Disposing the photoelectrode and the counter electrode and filling an electrolyte

It provides a method for producing a dye-sensitized solar cell comprising a.

In addition, the present invention forms a metal oxide nanoparticle layer having a laminated structure of two or more layers of the same or different type on one surface of a transparent conductive substrate on which a blocking layer is formed, and after forming a light scattering layer thereon, titanium tetrachloride (TiCl ₄ ) treatment Proceeding with;

Adsorbing a primary dye onto at least two metal oxide nanoparticle layers formed on the transparent conductive substrate;

Desorbing only the primary dye of at least one or more layers of the metal oxide nanoparticle layer of the upper portion of the two or more layers of the metal oxide nanoparticle layer to which the primary dye is adsorbed using a viscous basic desorbent;

Adsorbing a secondary dye on the desorption site to produce a photoelectrode having two or more metal oxide nanoparticle layers having a dye layer having a stacked structure having different absorption wavelengths and a light scattering layer thereon;

Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And

Disposing the photoelectrode and the counter electrode and filling an electrolyte

It provides a method for producing a dye-sensitized solar cell comprising a.

In addition, the method of the present invention, by repeating the desorption process and the resorption process of the dye may be laminated three or more dyes on the metal oxide nanoparticle layer formed on the light scattering layer.

In addition, the present invention is produced by the above method,

A photoelectrode formed on the transparent conductive substrate and including a metal oxide nanoparticle layer and a light scattering layer to which dye is adsorbed,

A counter electrode disposed opposite the photoelectrode and including a platinum layer formed on a transparent conductive substrate;

An electrolyte filling between the photoelectrode and the counter electrode,

The dye-adsorbed metal oxide nanoparticle layer provides a dye-sensitized solar cell having a multi-layered dye, including a dye layer having two or more stacked structures in which two or more dyes having different wavelengths are respectively adsorbed.

At this time, the dye oxide metal oxide nanoparticle layer is adsorbed

In the metal oxide nanoparticle layer formed of one layer, two or more dyes having different wavelengths are adsorbed in a stacked structure, or

In the metal oxide nanoparticle layer formed of two or more layers, two or more dyes having different wavelengths may be separately adsorbed to each layer to have a layered dye layer.

Hereinafter, the present invention will be described in detail.

Korean Patent Publication No. 2009-91870 developed by the present applicant provides a dye-sensitized solar cell having a multi-layered dye, but the method produces a polymer material by polymer coating in a process of desorbing the primary dye used. In this case, the polymer and the organic solvent used have a bad effect on the characteristics of the solar cell. In addition, the method may cause deterioration of organic dyes in the process of thermal polymerization of the polymer, it is difficult to apply to a large area module due to a complex process.

Thus, the conventional multi-layered dye-sensitized solar cell has a polymer coating to selectively desorb the dye by controlling the pores of the metal oxide nanoparticles, this process was complicated and adversely affected the performance of the solar cell.

Accordingly, the present invention provides a method for solving the above problems, and to provide an improved invention of the Republic of Korea Patent Publication No. 2009-91870. In other words, the present invention shows a high efficiency, while simplifying the desorption process and eliminating the desorption process using a thermal polymerization process and an aqueous solution to simplify and simplify the overall process, and a method for manufacturing a multi-layered dye-sensitized solar cell It is characterized by providing a dye-sensitized solar cell manufactured from.

The present invention forms a metal oxide nanoparticle layer on a conductive substrate to adsorb a primary dye having an absorption capability of a specific wavelength region, and then desorbs the upper layer to a desired thickness with a viscous basic solution without a separate polymer coating. The present invention relates to a multi-layered dye-sensitized solar cell using a method of resorbing a secondary dye capable of absorbing different wavelength bands, and a method of manufacturing the same.

In particular, the present invention reduces the average size of the pores of the metal oxide nanoparticles of the light absorption layer by about 10% through post-treatment of titanium tetrachloride (TiCl ₄ ) of the metal oxide nanoparticle layer before dye adsorption, the molecular weight of the basic material of the dye desorption solution By increasing, the dye was selectively desorbed only with a viscous desorption solution without a polymer coating. Therefore, the method according to the present invention can eliminate the coating and removal process of the polymer, it is possible to eliminate the cause of the thermal polymerization process of the polymer and the photoelectric characteristics of the solar cell is impaired due to the use of unnecessary organic solvent. In this case, the TiCl ₄ treatment method may be performed by immersing the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution having a concentration of 0.02 to 0.2 mol at 20 ° C. to 80 ° C. for 20 minutes to 20 hours. Preferably, the TiCl ₄ treatment method is to immerse the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution of 0.03 to 0.06 molar concentration at 50 ℃ to 80 ℃ for 20 minutes to 1 hour. The viscous basic desorbent has a viscosity of 20 cps to 1500 cps.

In addition, the present invention can eliminate the polymer formation-removal process previously used by using a large molecular weight tetrabutylammonium hydroxide solution instead of the conventional sodium hydroxide (NaOH) aqueous solution as the basic desorption solution.

Hereinafter, a method of manufacturing a dye-sensitized solar cell according to a preferred embodiment of the present invention and a dye-sensitized solar cell having a multi-layered dye prepared therefrom will be described in detail with reference to the drawings.

First, the manufacturing method of the dye-sensitized solar cell according to the first embodiment of the present invention,

Forming a metal oxide nanoparticle layer and a light scattering layer on one surface of the transparent conductive substrate on which the blocking layer is formed, and then performing titanium tetrachloride (TiCl ₄ ) treatment;

Adsorbing a primary dye on the metal oxide nanoparticle layer formed on the transparent conductive substrate;

Desorbing only the primary dye of the metal oxide nanoparticle layer of the upper portion of the metal oxide nanoparticle layer to which the primary dye is adsorbed using a viscous basic desorbent;

Preparing a photoelectrode having a metal oxide nanoparticle layer having a dye layer having a laminated structure having a different wavelength and a light scattering layer thereon by adsorbing a secondary dye having a different wavelength from the primary dye at the desorption site;

Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And

And opposing the photoelectrode and the counter electrode and filling the electrolyte.

In addition, the manufacturing method of the dye-sensitized solar cell according to a second embodiment of the present invention,

Forming a metal oxide nanoparticle layer having a laminated structure of two or more layers of the same or different type on one surface of the transparent conductive substrate on which the blocking layer is formed, forming a light scattering layer thereon, and then performing titanium tetrachloride (TiCl ₄ ) treatment;

Adsorbing a primary dye onto at least two metal oxide nanoparticle layers formed on the transparent conductive substrate;

Desorbing only the primary dye of at least one or more layers of the metal oxide nanoparticle layer of the upper portion of the two or more layers of the metal oxide nanoparticle layer to which the primary dye is adsorbed using a viscous basic desorbent;

By adsorbing a secondary dye having a different wavelength from the primary dye to the desorption site, to prepare a photoelectrode having two or more metal oxide nanoparticle layer having a dye layer of a laminated structure having a different wavelength and a light scattering layer formed thereon Making;

Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And

And opposing the photoelectrode and the counter electrode and filling the electrolyte.

In addition, the method according to the first embodiment and the second embodiment of the present invention in the step of manufacturing the photoelectrode, so that the metal oxide nanoparticle layer has a dye layer of two or more laminated structure having a different wavelength, desorption The process and the process of resorbing the dye can be repeated.

For example, in the first embodiment, after adsorbing the secondary dye, the metal oxide nanoparticle layer of the upper portion of the metal oxide nanoparticle layer in which the secondary dye is adsorbed using a viscous basic desorbent is used. Desorption of only the secondary dye, and the step of adsorbing additional dyes having a different wavelength from the primary and secondary dyes used in the photoelectrode to the desorption site of the secondary dye to further form a dye layer at least once It may further comprise the step. Therefore, the additional dye may be a tertiary dye, a quaternary dye, or the like, and may implement a desired form as necessary. Thus, the present invention can provide a dye-sensitized solar cell having a dye layer of a multi-layered structure.

In addition, in the case of the second embodiment, the additional procedure is the same, and using at least one layer of the two or more layers of the metal oxide nanoparticle layer on which the secondary dye is adsorbed, using a viscous basic desorbent, Desorbing only the secondary dye of the metal oxide nanoparticle layer, and adsorbing a third dye having a wavelength different from that of the primary and secondary dyes used in manufacturing the photoelectrode to the desorption site of the secondary dye to further form a dye layer. It may further comprise repeating one or more times.

At this time, in the method according to the second embodiment, the selection of the desorption site in the process of desorbing the dye using the basic desorption liquid can be adjusted as necessary. In addition, in the present invention, "at least one layer of the metal oxide nanoparticle layer of the upper portion is located in the form of the dye adsorbed on the two or more metal oxide nanoparticle layer, first formed on the surface in contact with the transparent conductive substrate It means the upper portion of the metal oxide nanoparticle layer. Thus, when using the method according to the second embodiment, if the metal oxide nanoparticle layer is formed of two layers, the "at least one layer of the metal oxide nanoparticle layer of the upper portion located" is on the transparent conductive substrate A second metal oxide nanoparticle layer on the first metal oxide nanoparticle layer directly contacted is shown. Therefore, the desorption site of the dye in this case may be the second metal oxide nanoparticle layer. In addition, when two or more dyes are used when the metal oxide nanoparticle layer is three or more layers, the desorption site of the dye may be a second metal oxide nanoparticle layer, a third metal oxide nanoparticle layer, or a mixed layer thereof. Therefore, when the multilayer metal oxide nanoparticle layer is stacked, the desorption site of the dye may be determined by the stacking order of the metal oxide nanoparticle layer.

Figure 2a shows the manufacturing process of the dye-sensitized solar cell having a multi-layered dye according to the first embodiment of the present invention. As shown in Figure 2a, the solar cell of the present invention (a) a general conductive transparent conductive substrate 10, the metal oxide precursor or nanoparticles and the like applied as a blocking layer 20 and then heat-treated. (b) A metal oxide nanoparticle paste including metal oxide nanoparticles having an average particle diameter of 1 nm to 80 nm, a binder resin, and a solvent is coated on the blocking layer and heat treated to form a metal oxide nanoparticle layer for use as a light absorption layer. Subsequently, (c) a paste including metal oxide nanoparticles having a mean particle size of 100 nm to 2000 nm, a binder resin, and a solvent is applied onto the metal oxide nanoparticle layer formed in (c) and heat treated to form a light scattering layer. Thereafter, (d) the primary dye material 31a is adsorbed only on the sintered metal oxide nanoparticle layer. And, (e) the basic solution is induced to desorb only the dye present on top of the metal oxide nanoparticle layer. By this process, the metal oxide 31c to which the dye is not adsorbed is present. Subsequently, (f) only the portion where the dye is desorbed on the upper portion of the metal oxide nanoparticle layer in which the metal oxide 31c is not adsorbed is adsorbed with a different type of secondary dye material 31b to form a dual dye of a stacked structure. The structure of the photoelectrode including the light absorption layer 30 including the configured metal oxide nanoparticles may be provided. In addition, by repeating this process, the present invention enables the formation of a structure including not only a double layer but also triple, quadruple or more multiple dye layers in a single nanoparticle layer.

In this case, the metal oxide nanoparticle paste for forming the metal oxide nanoparticle layer is prepared by mixing the metal oxide nanoparticles with a solvent to prepare a colloidal solution of the viscosity of the metal oxide dispersed 5 × 10 ⁴ to 5 × 10 ⁵ cps After mixing the binder resin, it is prepared by removing the solvent for 30 minutes-1 hour at 40-70 ℃ with a Rotor Evaporator. The metal oxide nanoparticles may be prepared by hydrothermal synthesis, or may be prepared using commercially available metal oxide nanoparticles. In addition, the mixing ratio of the metal oxide nanoparticles, the binder resin, and the solvent is not particularly limited. For example, the metal oxide: Terpineol: ethyl cellulose: lauric acid is 1: 2 to 6 : 0.2 to 0.5: can be used by mixing in a weight ratio of 0 to 0.3.

In addition, in the present invention, the light scattering layer is formed to increase energy conversion efficiency, and the metal oxide nanoparticle paste for forming the light scattering layer is not particularly limited in its manufacturing method, and may be manufactured using the same method as described above. have.

Metal oxide nanoparticles that can be used in the light absorption layer and the light scattering layer of the photoelectrode are Ti, Zr, Sr, Zn, In, Yr, La, V, Mo, W, Sn, Nb, Mg, Al, Y, Sc, Any metal oxide selected from the group consisting of Sm and Ga, or a composite oxide thereof may be used. Preferably, the metal oxide nanoparticle layer and the light scattering layer, which are light absorption layers of the photoelectrode, include titanium (Ti) oxide, zirconium (Zr) oxide, strontium (Sr) oxide, zinc (Zn) oxide, indium (In) oxide, and lanta, respectively. La oxide, vanadium (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, tin (Sn) oxide, niobium (Nb) oxide, magnesium (Mg) oxide, aluminum (Al) oxide It may include one or more materials selected from the group consisting of yttnium (Y) oxide, scandium (Sc) oxide, samarium (Sm) oxide, gallium (Ga) oxide, and strontium titanium (SrTi) oxide. More preferably, the light absorption layer of the metal oxide nanoparticle layer and the light scattering layer of the photoelectrode in the group consisting of titanium oxide (TiO ₂ ), zinc oxide (ZnO), tin oxide (SnO ₂ ) and tungsten oxide (WO ₃ ). Can be used to select.

In the case of the metal oxide nanoparticle layer in which the dye used as the light absorption layer is adsorbed, the nanoparticle size of the metal oxide is preferably 1 nm to 80 nm in average particle diameter. In addition, the average particle diameter of the metal oxide nanoparticles used in the light scattering layer is preferably 100 nm to 2000 nm, more preferably 200 nm to 600 nm.

The kind of the binder resin is not particularly limited, and polymers serving as ordinary binders may be used. Preferably, a polymer should be selected in which organic matter does not remain after heat treatment. Suitable polymers include polyethylene glycol (PEG), polyethylene oxide (PEO), polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), ethylcellulose and the like. In order to more evenly disperse the prepared paste, the three ceramic rolls may be dispersed once more by adding the paste to a three-roll grinder turning like a cog wheel and post-processing.

The solvent may be used without particular limitation as long as it is used in the preparation of the colloidal solution. Examples of the solvent include ethanol, methanol, terpineol, lauric acid, THF, and water.

In the present invention, an example of the metal oxide nanoparticle paste composition may be a composition containing titanium oxide, terpineol, ethyl cellulose and lauric acid or a composition of titanium oxide, ethanol and ethyl cellulose.

In addition, in the present invention, the thickness of the dye-adsorbed metal oxide nanoparticle layer and the light scattering layer may be 5 μm to 60 μm. In addition, the thickness of the dye-adsorbed metal oxide nanoparticle layer may be 2μm to 50μm, the thickness of the light scattering layer may be 2μm to 10μm.

In addition, the blocking layer 20 is preferably formed by spin-coating a metal oxide precursor or a nanoparticle solution on a transparent conductive substrate, followed by heat treatment at least at a high temperature of 450 to 500 ° C. in air or oxygen for 10 minutes. The metal oxide nanoparticle layer 32 is applied to the metal oxide nanoparticle paste prepared above on the blocking layer and then in air or oxygen for 10 to 120 minutes at 400 to 550 ° C., preferably at a high temperature of 450 to 500 ° C. It is preferable to form by heat-processing for 30 minutes.

In addition, in the present invention, the dye substances 31a and 31b are adsorbed to generate photocharges on the metal oxide nanoparticle layer formed on the photoelectrode.

The primary dye material 31a preferably includes a material capable of absorbing visible light, infrared light, and ultraviolet light. For example, conventional metal complexes, inorganic dyes, organic dyes, and the like may be used. Preferably, the dye material is ruthenium (Ru) complex dye N719 (bis (tetrabutylammonium) -cis- (dithiocyanato) -N, N'-bis (4-carboxylato-4'-carboxylic acid-2,2'-bipyridine) ) ruthenium (II)), N749 ((4,4 ', 4' '-tricarboxy-2,2': 6 ', 2'-terpyridine) ruthenium (II)), CdSe as inorganic dye, P5 as organic dye Can be used. As a dye adsorption method, a method used in a general dye-sensitized solar cell may be used. For example, a method of immersing a photoelectrode in which metal oxide nanoparticles are formed in a dispersion containing a dye and then adsorbing at an appropriate temperature may be employed. It is available. The solvent for dispersing the dye is not particularly limited, but preferably acetonitrile, dichloromethane or an alcohol solvent may be used. After adsorbing the dye, the method may include washing the dye that is not adsorbed by a solvent washing method.

Then, as described above, the present invention is a primary dye of the portion located on the upper side of the portion of the first dye is adsorbed in the metal oxide nanoparticle layer adsorbed using a viscous basic desorption solution Detach the bay.

The components basically included in the basic solution for desorption vary widely, and the kind thereof is not particularly limited. For example, the basic solution may be a solution in which basic compounds such as sodium hydroxide and tetrabutylammonium hydroxide are dissolved in water, an organic solvent or a polymer mixture solution.

However, it is preferable to use a basic solution using an organic solvent such as ethanol rather than water in order to minimize the damage of the primary dyes and oxides that are already adsorbed. In addition, in order to effectively control the thickness of desorption, it is preferable to use tetrabutylammonium hydroxide or the like having a higher molecular weight than a low molecular material such as sodium hydroxide. In addition, in the present invention, in order to control the degree of desorption, the number of desorption, the exposure time of the desorption liquid, the type of desorption material, etc. can be adjusted. In particular, in the present invention, a specific viscous polymer is used to impart viscosity to the basic desorption solution.

Accordingly, the viscous basic desorbent used in the present invention is characterized by using a mixed solution of aqueous solution of water or ethanol, preferably a tetrabutylammonium hydroxide solution dissolved in ethanol and a viscous polymer . The aqueous tetrabutylammonium hydroxide solution and the viscous polymer may be mixed at a volume ratio of 5: 1 to 1: 10. In addition, the basic desorption solution used in the present invention preferably has a viscosity of 20 cP to 1500 cP.

The viscous polymer is polypropylene glycol, polyurethane, polyethylene oxide, polypropylene oxide, polyethylene glycol, chitosan, chitin, polyacrylamide, polyvinyl alcohol, polyacrylic acid, cellulose, ethyl cellulose, polyhydroxyethyl methacrylic acid, polyethylene , Polymeric materials such as polypropylene, polyethylene naphthalate, polyethylene terephthalate, and the like dissolved in an organic solvent may be mixed and used in the basic solution.

Preferably, in the present invention, it is preferable to use an aqueous solution of tetrabutylammonium hydroxide and polypropylene glycol in a volume ratio of 5: 1 to 1:10.

Thus, the present invention dissolves a basic material having a large molecular weight in ethanol, which can minimize dye damage, and gives viscosity to a desorption solution using a polymer material, thereby eliminating the need for a separate polymer coating and thermal polymerization process. Desorption of the dye may be induced.

In this case, the portion located toward the upper portion of the portion where the primary dye is adsorbed means a portion corresponding to 10 to 90% of the total thickness of the metal oxide nanoparticle layer to which the primary dye is adsorbed. Therefore, the present invention desorbs the surface thickness of the portion of the dye adsorption portion located in the upper portion to be desorbed from the dye layer adsorbed to the metal oxide nanoparticle layer to the desired thickness, so as to remove two or more other dyes different from the primary dye. It can additionally be adsorbed.

In addition, the secondary dye material for adsorbing to the site where the upper portion of the primary dye is desorbed may use the same or different absorption wavelength band characteristics of the primary dye. For example, the dye material is ruthenium (Ru) complex dye N719 (bis (tetrabutylammonium) -cis- (dithiocyanato) -N, N'-bis (4-carboxylato-4'-carboxylic acid-2,2'- bipyridine) ruthenium (II)), N749 ((4,4 ', 4' '-tricarboxy-2,2': 6 ', 2'-terpyridine) ruthenium (II)), inorganic dye CdSe, organic dye P5 Etc. can be used. The adsorption method of the dye is the same as the adsorption method of the primary dye, it is possible to adjust the adsorption time, the concentration of the dye, the molecular size of the dye and the like to control the penetration depth of the secondary dye.

In addition, according to the present invention, it is possible to further form a third or more dye layer in the laminated structure in which the primary and secondary dye layers are formed (FIGS. 2B and 2C). To this end, the present invention, it is possible to form a multiple dye layer by repeating the process of selective desorption of the top dye, and resorption of the additional dye one or more times. At this time, by adjusting the depth of the desorption of the upper layer of the metal oxide nanoparticle layer and the depth of resorption, the adsorption of the additional dye can be controlled, and the depth of the desorption and the depth of the resorption can be controlled within the desorption process and the resorption process of the additional dye. It is controlled by all the variables. That is, according to the present invention, the second dye is desorbed, and the second dye is desorbed, and the second dye is desorbed, and the second dye is desorbed after the second dye is resorbed. , A dye layer having a dye layer having the same or different wavelength as that of the primary and secondary dye layers by resorbing the additional dye having a different wavelength from the primary and secondary dyes and removing the polymer material at least once. It may further include. Preferably, the dye material is N719 (bis (tetrabutylammonium) -cis- (dithiocyanato) -N, N'-bis (4-carboxylato-) which is the same ruthenium (Ru) complex dye as the primary and secondary dyes used above. 4'-carboxylic acid-2,2'-bipyridine) ruthenium (II)), N749 ((4,4 ', 4' '-tricarboxy-2,2': 6 ', 2'-terpyridine) ruthenium (II) ), CdSe, which is an inorganic dye, and P5, which is an organic dye, may be used. In addition, the portion located above the portion where the secondary dye is adsorbed may correspond to 10 to 90% of the total thickness of the metal oxide nanoparticle layer adsorbed on the secondary dye, and the dye should be desorbed as needed. The thickness of the surface layer of the upper part can be adjusted.

In addition, in order to manufacture the counter electrode 70 required for forming a solar cell, the present invention is preferably coated with a platinum solution on a transparent conductive substrate, and then heat treated at a high temperature of about 400 degrees to manufacture the counter electrode.

The transparent conductive substrate 10 may be selected from those conventional in the art to which the present invention pertains, and preferably, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate (PC), polypropylene ( Indium tin oxide (ITO), fluorine tin oxide (FTO), ZnO-Ga _{2 on} a transparent plastic or glass substrate comprising any one of PP), polyimide (PI), and triacetylcellulose (TAC) One coated with a conductive film including any one of O ₃ , ZnO-Al ₂ O ₃ , and SnO ₂ -Sb ₂ O ₃ may be used, but is not limited thereto.

On the other hand, the present invention is a dye-sensitized solar cell comprising a light absorbing layer 30 having a multiple dye layer by placing the two electrodes 70, 80 prepared by the above facing each other facing each other and then bonding and filling the electrolyte Can be prepared.

The electrolyte 40 is illustrated as one layer for convenience of description in FIG. 2C, but is actually uniformly dispersed in the metal oxide nanoparticle layer, which is a porous membrane, in the space between the light absorption layers 30.

The dye-sensitized solar cell according to the present invention is characterized in that it has a laminated structure of a multi-dye layer and a multi-layered metal oxide nanoparticle layer, the electrolyte 40 except for this has a conventional configuration in the technical field to which the present invention belongs It may include, and the production method is also not particularly limited because it can be prepared using conventional methods.

For example, the electrolyte 40 may be used as an iodide / triodide pair that may serve to transfer electrons from the counter electrode 70 by oxidation-reduction to a dye in the light absorption layer 30.

This method of the present invention can broaden the absorption range of light by adsorbing multiple dyes in a single oxide particle layer of a conductive substrate in a stack, and discontinuous between the metal oxide particle layer adsorbed with the primary dye and the metal oxide particle layer adsorbed with the additional dye. A stacked structure is formed within a single oxide particle layer without significant space to effectively express the characteristic bands of the two dyes. In addition, the present invention is the characteristics of the solar cell by controlling the molecular weight of the basic solute desorbs the dye, without the process of forming and removing the polymer, as described in the patent application 10-2008-0017071 developed by the present applicant Has greatly improved and the process has been greatly simplified. In addition, the desorption solute was dissolved in an organic solvent, in particular ethanol, rather than an aqueous solution to prevent the reduction of properties due to water. In addition, the present invention can maximize the electron injection efficiency of each dye by laminating a metal oxide nanoparticle layer suitable for each laminated dye used in the dye-sensitized solar cell to match the stacked dye layer.

In addition, in the manufacturing method according to the second embodiment of the present invention, except that the method of forming the metal oxide nanoparticle layer on which the dye having a stacked structure is adsorbed is different, the method of the counter electrode is the same as that of the first embodiment. To prepare a dye-sensitized solar cell.

Next, a method of forming a metal oxide nanoparticle layer adsorbed with a dye having a laminated structure according to the second embodiment will be described.

First, in the present invention, two or more layers of metal oxide nanoparticles having the same or different type of laminated structure are laminated in order with a predetermined thickness so as to have a desired stacking number on a transparent conductive substrate before adsorbing the dye. At this time, the metal oxide nanoparticle layer having a laminated structure of two or more layers prior to adsorbing the dye is transparent conductive using first and second metal oxide nanoparticle pastes containing the same or different kinds of metal oxide nanoparticles. Sequentially applying and heat-treating the blocking layer formed on the substrate to form a double layered metal oxide nanoparticle layer, or one or more metal oxide nanoparticle pastes that are the same as or different from the first and second metal oxide nanoparticle pastes. It can be formed by repeating the process of coating and heat treatment on the metal oxide nanoparticle layer of the double-layer structure using one or more times. In addition, the metal oxide nanoparticles may be the same or different types. Preferably, the metal oxide nanoparticle layer having a laminated structure of two or more layers prior to adsorbing the dye may include a metal oxide nanoparticle paste including metal oxide nanoparticles having an average particle diameter of 1 nm to 80 nm, a binder resin, and a solvent. After coating and heat-treating to form a metal oxide nanoparticle layer, the process of coating and heat-treating the metal oxide nanoparticle paste thereon may be performed repeatedly two or more times. That is, in the case of having a metal oxide nanoparticle layer having a two-layer structure, a transparent conductive layer having a blocking layer formed by using the first and second metal oxide nanoparticle pastes containing the same or different types of metal oxide nanoparticles of A and B Sequential application and heat treatment on one surface of the substrate to form a metal oxide nanoparticle layer of a double laminated structure. Thereafter, a light scattering layer is formed on the metal oxide nanoparticle layer.

The primary dye is adsorbed onto the two or more metal oxide nanoparticle layers, and the upper portion of the two or more metal oxide nanoparticle layers on which the primary dye is adsorbed is formed using a viscous basic desorbent. Only the primary dye of at least one or more metal oxide nanoparticle layers is desorbed. In addition, by adsorbing a secondary dye having a wavelength different from the primary dye to the desorption site, the photoelectrode having two or more metal oxide nanoparticle layers having a dye layer of a laminated structure having a different wavelength and a light scattering layer thereon Can be prepared.

In addition, when the metal oxide nanoparticle layer having a three-layer structure as shown in Figure 2c, the method is similar except that one more metal oxide nanoparticle layer is formed in the above configuration.

That is, the present invention prepares the first to third metal oxide nanoparticle pastes containing the same or different kinds of metal oxide nanoparticles. Thereafter, the first metal oxide nanoparticle paste is coated on the transparent conductive substrate to a predetermined thickness and heat-treated to form the first metal oxide nanoparticle layer (including metal oxide A). Thereafter, the second metal oxide nanoparticle paste is coated on the first metal oxide nanoparticle layer to a predetermined thickness, and heat treated to form a second metal oxide nanoparticle layer (including metal oxide B). Then, the third metal oxide nanoparticle paste is coated on the second metal oxide nanoparticle layer to a predetermined thickness and heat treated to form a third metal oxide nanoparticle layer (including metal oxide C).

Thereafter, in order to form a light scattering layer in a structure in which the first to third metal oxide nanoparticle layers are sequentially stacked, light scattering is performed using a paste having the same conditions as in the first embodiment on the third metal oxide nanoparticle layer. Form a layer. Subsequently, the substrate having the first to third metal oxide nanoparticle layers (light absorbing layer) and the light scattering layer is immersed in a primary dye to adsorb the primary dye onto the transparent conductive substrate.

And, using a viscous basic desorption liquid, at least one or more layers of metal oxide nanoparticle layers positioned above, preferably second and third, among the three layers of metal oxide nanoparticle layers on which the primary dye (dye A) is adsorbed. Only the primary dye of the third metal oxide nanoparticle layer is desorbed. Then, the substrate obtained above is immersed in a secondary dye (dye B) to adsorb the secondary dye to the desorption site including the second and third metal oxide nanoparticle layers. Subsequently, among the second and third metal oxide nanoparticle layers in which the secondary dye is adsorbed using a viscous basic desorbent solution, at least one or more metal oxide nanoparticle layers positioned upward, preferably a third metal. Only the secondary dye of the oxide nanoparticle layer is desorbed. Subsequently, the substrate obtained above is immersed in a tertiary dye (dye C) to adsorb the tertiary dye to the desorption site including the third metal oxide nanoparticle layer.

Through this process, the metal oxide nanoparticle layer serving as the light absorption layer, as shown in Figure 2c, the dye A is adsorbed to the metal oxide A, the dye B is adsorbed to the metal oxide B, the dye C to the metal oxide C It is possible to obtain a form having a laminated structure adsorbed.

In addition, the photoelectrode has a form having a light scattering layer on the light absorption layer of the stacked structure.

In addition, after forming a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate in the same manner as in the first embodiment, the photoelectrode and the counter electrode are disposed to face each other and filled with an electrolyte to form a multilayered dye-sensitized solar cell. Can be prepared.

On the other hand, the present invention provides a dye-sensitized solar cell produced by the above method.

The dye-sensitized solar cell of the present invention is formed on a transparent conductive substrate, a photoelectrode including a metal oxide nanoparticle layer adsorbed by a dye, a counter electrode including a platinum layer disposed opposite to the photoelectrode and formed on a transparent conductive substrate, and It may have a structure including an electrolyte filling between the photoelectrode and the counter electrode. Preferably, the dye-adsorbed metal oxide nanoparticle layer is characterized by including two or more dye layers each of which two or more dyes having different wavelengths are adsorbed. In addition, a light scattering layer may be formed on the dye oxide-adsorbed metal oxide nanoparticle layer.

Here, the form in which the dye is adsorbed in the dye oxide-adsorbed metal oxide nanoparticle layer may be selective according to the method of the first embodiment and the second embodiment. For example, in the form, two or more dyes having different wavelengths may be adsorbed in a stacked structure in the metal oxide nanoparticle layer formed in one layer, or two or more dyes having different wavelengths in the metal oxide nanoparticle layer formed in two or more layers. The dye may be adsorbed separately to each layer to have a layered dye layer. That is, according to the present invention, after forming the metal oxide nanoparticle layer as a single layer on the transparent conductive substrate, two or more dyes may be formed in a portion in a laminated structure. In addition, the present invention after forming a metal oxide nanoparticle layer of the same or different type on the transparent conductive substrate, respectively, in a laminated structure, and then two or more dyes having different wavelengths in each of the metal oxide nanoparticle layer of the laminated structure in a laminated structure It may be formed. That is, as shown in Figure 2b, by applying a nanooxide suitable for the stacked dye, it is possible to increase the electron injection efficiency (electron injection efficiency), which is the efficiency of electron transfer from the dye to the nanooxide.

Figure 2b shows the structure of a multi-dye laminated dye-sensitized solar cell according to a first embodiment of the present invention. As illustrated in FIG. 2B, the dye-sensitized solar cell of the present invention includes a metal oxide nanoparticle layer having a blocking layer 20 on a transparent substrate 10 and having a dye layer A, a dye layer B, and a dye layer C thereon ( A photoelectrode 80 comprising a light scattering layer 32 and a light scattering layer 32, a counter electrode 70 having a platinum layer 60 on a transparent substrate 10 disposed opposite the photoelectrode 80, and the light. An electrolyte 40 filled between the electrode and the counter electrode, and an adhesive resin 50 may be provided. The metal oxide nanoparticle layer is used as the light absorption layer.

Figure 2c shows the structure of the dye-sensitized solar cell applying the metal oxide nanoparticles to the dye laminated in each layer according to the second embodiment of the present invention. As disclosed in FIG. 2C, the dye-sensitized solar cell of the present invention includes a blocking layer 20 on the transparent substrate 10 and the same or different metal oxides A, B, and C on the transparent substrate 10, respectively. The photoelectrode 80 including the metal oxide nanoparticle layer 30 and the light scattering layer 32 on which C is adsorbed, and the platinum layer 60 is disposed on the transparent substrate 10 and disposed opposite to the photoelectrode 80. The counter electrode 70, an electrolyte 40 filled between the photoelectrode and the counter electrode, and an adhesive resin 50 may be provided. The metal oxide nanoparticle layer is used as the light absorption layer.

The dye layers A to C are light absorbing layers, and the dyes included therein may have different absorption wavelengths of different kinds. In addition, according to the present invention, the dye layer may further include a dye having the same or different wavelength as the dye used in the metal oxide nanoparticle layer to which the dye is adsorbed. In addition, although not shown in FIG. 2A for convenience, the dye layer includes a metal oxide nanoparticle layer. In addition, the metal oxide nanoparticles in the nanoparticle layer of the metal oxide on which the dye is adsorbed may have an average size of 1 nm to 80 nm, and may include one or more kinds of metal oxides of the same or different type. Preferably, the metal oxides A to C may use the same or different types, and may have a form in which metal oxides having different particle sizes or different metal oxides are mixed.

Dye-sensitized solar cell of the present invention provided by such a method, as shown in Figure 3, it can absorb a wider range of sunlight compared to conventional dye-sensitized solar cell containing a single dye, including multiple dye layers. It can be seen.

The present invention can implement a multi-layered dye-sensitized solar cell of higher performance by changing the process of the dye-sensitized solar cell is a multilayer of the conventionally published dye. By controlling the number of times of the desorption step using the viscous desorption solution, the lamination thickness of the lower layer dye can be controlled. The multilayered dye-sensitized solar cell manufactured according to the present invention showed significantly higher energy conversion efficiency than the energy conversion efficiency shown when the dye-sensitized solar cell using one dye was optimized, and was easy to apply to a large area module by simplifying the process. I did it. In addition, it is possible to increase the electron injection efficiency by multi-layering a nano oxide electrode suitable for each laminated dye.

1A is a schematic diagram of an organic dye solar cell configuration.
1B is a schematic diagram of a tandem structured organic dye solar cell previously studied.
Figure 2a shows a manufacturing process of an organic dye solar cell having a multi-layered dye according to a first embodiment of the present invention.
Figure 2b shows the structure of a dye solar cell having a multi-layered dye according to a first embodiment of the present invention.
Figure 2c shows the structure of a dye solar cell having a multi-layered dye by stacking the metal oxide nanoparticle layer according to a second embodiment of the present invention by adsorbing the dye.
Figure 3 is a schematic diagram showing a comparison of the absorption range of the conventional single dye structure and the broad absorption range of the multiple dye layered structure of the present invention.
4 shows measurement results of incident photon-current conversion efficiency of Example 2, Comparative Example 1, and Comparative Example 2. FIG.
5 shows measurement results of incident photon-current conversion efficiency of Example 3, Comparative Example 3, and Comparative Example 4. FIG.

Hereinafter, preferred embodiments of the present invention are described. However, the following examples are only illustrated to aid the understanding of the present invention, but the contents of the present invention are not limited to the following examples.

Example  One

(Manufacture of Multi-wavelength Absorption Dye-Sensitized Solar Cell with Multi-Dye Lamination Structure)

Before and after, a glass substrate coated with FTO was prepared as a substrate for the rear electrode. The counter electrode was prepared by coating a H ₂ PtCl ₆ solution on the conductive surface of the substrate for the rear electrode and performing heat treatment at 400 ° C. for 20 minutes. The conductive layer of the front electrode substrate was spin coated with 0.15 M titanium (IV) bis (ethyl acetoacetate) diisopropoxide solution and heat-treated at 500 ° C. for at least 10 minutes to form a blocking layer.

Subsequently, a metal oxide nanoparticle paste containing titanium oxide nanoparticles (average particle diameter: 20 nm), a binder polymer (ethyl cellulose), and a solvent (Terpineol) is applied onto the front electrode substrate (doctor blade) Method), and then the substrate was heat-treated at 500 ° C. for 30 minutes to form a porous titanium oxide nanoparticle layer used for the front electrode.

Then, a metal oxide nanoparticle paste including titanium oxide nanoparticles capable of scattering light (average particle diameter: 500 nm), a binder polymer (ethyl cellulose), and a solvent (Terpineol) is formed on the titanium oxide nanoparticle layer formed on the substrate. After coating, the substrate was heat treated at 500 ° C. for 30 minutes to form a light scattering layer. Subsequently, in order to increase the photocurrent and to adjust the pore size of the nanooxide to facilitate the desorption thickness control, the substrate on which the titanium oxide nanoparticle layer and the light scattering layer are formed is immersed in an aqueous TiCl ₄ solution of 0.04 molar concentration at 70 ° C. for 30 minutes. It was. At this time, the thickness of the blocking layer is about 30 nm, and the thickness of the titanium oxide nanoparticle layer is about 35 μm including the light scattering layer. That is, the titanium oxide nanoparticle layer used as the light absorption layer is about 30 μm and the light scattering layer is about 5 μm.

Subsequently, the front substrate was ruthenium-based photosensitive dye N719 (bis (tetrabutylammonium) -cis- (dithiocyanato) -N, N'-bis (4-carboxylato-4'-carboxylic acid-2,2'-bipyridine) ruthenium (II)) was immersed in an ethanol solution containing 0.5 mM at room temperature for 16 hours to adsorb the photosensitive dye only on the particle surface of the porous metal oxide layer.

A solution of tetrabutylammonium hydroxide dissolved in ethanol at a concentration of 100 mM and polypropylene glycol for imparting viscosity to the solution were mixed at a volume ratio of 1: 1 to prepare a basic desorbent solution having viscosity. After washing the substrate having the photosensitive dye adsorbed with ethanol, the prepared basic desorption solution was dropped onto the substrate, and after 30 seconds, the substrate was washed with ethanol, whereby the portion located toward the top of the metal oxide nanoparticle layer on which the dye was adsorbed was removed. Desorption was performed at a thickness of about 5-6 μm. After repeating the desorption process 3-4 times, another ruthenium-based photosensitive dye N749 ((4,4 ', 4' '-tricarboxy-2,2': 6 ', 2'-terpyridine) ruthenium (II)) The photosensitive dye was adsorbed to the desorption site for 6 hours at 40 ° C. by immersion in an ethanol solution containing 0.5 mM and Cheno Deoxycholic acid 20 mM. In this case, N719 and N749 double dye layer is formed on the porous metal oxide nanoparticle layer, and they have a laminated structure.

(Electrolyte injection, suture)

After joining the front electrode and the rear electrode, the acetonitrile electrolyte containing PMII (0.7M) and I2 (0.05M) was injected into the space therebetween, and then sealed and multi-wavelength having a double dye stack structure. An absorbing dye-sensitized solar cell was prepared.

Example  2

In order to compare the contribution of the current and efficiency improvement to the dye layer structure of the present invention, through the manufacturing process of Example 1, the lower layer of the titanium oxide nanoparticle layer having a thickness of 30μm N719, the upper layer is composed of N749 A laminated structure was produced.

Comparative example  One

In order to compare with Example 2, a unit cell was prepared in which the N719 dye was present only in the lower layer and the dye was not adsorbed in the upper layer.

Comparative example  2

In comparison with Example 2, a unit cell was prepared in which only N749 dye was present in the upper layer and no dye was adsorbed in the lower layer.

Example  3

In order to compare the contribution of the current and efficiency improvement to the dye layer structure of the present invention through the manufacturing process of Example 1, the lower layer of the titanium oxide nanoparticle layer having a thickness of 30 μm is P5 absorbing short wavelength, the upper layer is N749 A double layered structure was constructed.

Example  4

In the same manner as in Example 1, but the lower layer of the titanium oxide nanoparticle layer having a thickness of 30 μm was prepared a triple layered structure as shown in Figure 2b consisting of P5 absorbing short wavelength, the middle layer is N719, the upper layer is N749. .

Comparative example  3

In order to compare with Example 3, the unit cell was prepared in which the P5 dye was present only in the lower layer and the dye was not adsorbed in the upper layer.

Comparative example  4

In order to compare with Example 3, a unit cell was prepared in which only N749 dye was present in the upper layer and no dye was adsorbed in the lower layer.

Comparative example  5 and 6

A dye-sensitized solar cell of a single dye layer was fabricated by optimizing titanium oxide nanoparticle thickness and electrolyte using N749 dye (Comparative Example 5) and N749 dye (Comparative Example 6), which are widely used Ru-based dyes.

Experimental Example

The photoelectric characteristics (photocurrent density, open voltage, charge factor, energy conversion efficiency) of each dye-sensitized solar cell manufactured in Examples 2 to 3 and Comparative Examples 1 to 6 were measured using a solar simulator (Xe lamp [ 300 W, Oriel], AM1.5 filter, and Keithley SMU2400) and the results are shown in Tables 1 and 2. 4 shows current-voltage measurement results of the dye-sensitized solar cells of Example 2 and Comparative Examples 1 to 2. FIG. The measurement was masked by the black mask except for the active area to prevent scattered light from the side. The active area is about 0.4 cm 2.

In addition, the incident photon-to-current conversion efficiency (IPCE) of each dye-sensitized solar cell prepared in Examples 2 to 3 and Comparative Examples 1 to 3 was measured. 5 shows current-voltage measurement results under 1.5 AM light irradiation conditions of Example 3 and Comparative Examples 3 to 4. FIG.

division Photocurrent Density (mA / ㎠) Open voltage (mV) Fill factor (%) efficiency(%) Example 2 19.30 740.2 68.63 9.80 Comparative Example 1 15.68 725.0 70.40 8.00 Comparative Example 2 15.92 654.2 68.04 7.09

As shown in Table 1 and Figure 4, a dye-sensitized solar cell (Example 2) having a double dye stack structure in which the N749 dye is adsorbed on the upper portion and the N719 dye is adsorbed on the lower portion (Example 2) is a cell in which the N719 dye is adsorbed only on the lower portion (Comparative Example) Compared to 1) and the cell in which the N749 dye was adsorbed only on the upper part (Comparative Example 2), high photocurrent was shown. The reason is that the N719 has a high IPCE value in the wavelength range of 400 nm to 600 nm, and the N749 absorbs even the debt in the 900 nm wavelength range. This is because it absorbs light of wavelength zero. Therefore, in terms of energy conversion efficiency, the efficiency of 9.80% is improved by 18% compared to Comparative Examples 1 and 2.

division Photocurrent Density (mA / ㎠) Open voltage (mV) Fill factor (%) efficiency(%) Example 3 18.19 649.4 68.08 8.04 Comparative Example 3 3.87 539.2 75.34 1.57 Comparative Example 4 15.67 701.9 68.99 7.59 Comparative Example 5 15.06 824.3 73.10 9.08 Comparative Example 6 17.86 730.5 67.54 8.81

In addition, as shown in Table 2 and Figure 5, the dye-sensitized solar cell (Example 3) having a double-dye laminate structure in which the N749 dye is adsorbed on the top and P5, which is a yellow dye, is adsorbed on the bottom (Example 3). Compared to the battery (Comparative Example 3) and the cell (Comparative Example 4) in which the P5 dye was adsorbed only on the upper portion, high photocurrent values were shown. In other words, the N749 dye absorbs light up to 900 nm, but has a low IPCE value in the range of 300 nm to 400 nm. Therefore, the N749 dye can reinforce the short wavelength region of N749 by adsorbing P5, a dye that absorbs short wavelengths under the metal oxide. High photocurrent values can be obtained.

In addition, as shown in Table 2, dye-sensitized solar cells using the widely used and high efficiency dyes N719 and N749, and optimized the light absorption layer thickness and electrolyte (Comparative Example 5: N719, Comparative Example 6: N749) Even so, the solar cell (Example 2) having the double lamination dye of the present invention showed higher efficiency compared to Comparative Examples 5 and 6.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and a person skilled in the art does not depart from the spirit and scope of the present invention described in the above-described range and the appended claims. It will be appreciated that various changes and modifications can be made within the scope of the invention.

The present invention simplifies the process of multi-layered solar cells and improves the performance of the solar cells. Through this, it can be applied to the production of multi-wavelength absorbing dye-sensitized solar cells that can absorb a wide range of sunlight.

10: transparent conductive substrate
20: blocking layer
30: light absorption layer
31a: primary dye, 31b: secondary dye
31c: Metal oxides without dye adsorption
32: light scattering layer
40: oxidation / reduction electrolyte
50: bonding resin 60: platinum layer
70: counter electrode (or rear electrode)
80: photoelectrode (or front electrode)

Claims (25)

Forming a metal oxide nanoparticle layer on one surface of the transparent conductive substrate on which the blocking layer is formed, forming a light scattering layer on the metal oxide nanoparticle layer, and then performing titanium tetrachloride (TiCl ₄ ) treatment;
Adsorbing a primary dye on the metal oxide nanoparticle layer formed on the transparent conductive substrate;
Desorbing only the primary dye in the upper portion of the metal oxide nanoparticle layer to which the primary dye is adsorbed, using a viscous basic desorbent having a viscosity of 20 cps to 1500 cps;
A photoelectrode having a metal oxide nanoparticle layer having a dye layer having a laminated structure having a different wavelength and a light scattering layer formed thereon by adsorbing a secondary dye having a different wavelength from the primary dye on a portion where only the primary dye is desorbed. Preparing a;
Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And
Disposing the photoelectrode and the counter electrode and filling an electrolyte
Including;
The TiCl ₄ treatment method includes immersing the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution having a concentration of 0.02 to 0.2 mol at 20 ° C. to 80 ° C. for 20 minutes to 20 hours.
The viscous basic desorption solution is a method for producing a dye-sensitized solar cell using a mixed solution of tetrabutylammonium hydroxide aqueous solution and a viscous polymer dissolved in a water-soluble solvent of water or ethanol. The method of claim 1, wherein the TiCl ₄ treatment method comprises immersing the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution having a concentration of 0.03 to 0.06 molar at 50 ° C. to 80 ° C. for 20 minutes to 1 hour. Method for producing a dye-sensitized solar cell. The method of claim 1, wherein the viscous polymer is polypropylene glycol, polyurethane, polyethylene oxide, polypropylene oxide, polyethylene glycol, chitosan, chitin, polyacrylamide, polyvinyl alcohol, polyacrylic acid, cellulose, ethyl cellulose, polyhydroxy Ethyl methacrylic acid, polyethylene, polypropylene, polyethylene naphthalate and polyethylene terephthalate is selected from the group consisting of one or more, dye-sensitized solar cell manufacturing method. The metal oxide nanoparticle layer of claim 1, wherein the portion of the metal oxide nanoparticle layer adsorbed on the upper portion corresponds to 10 to 90% of the total thickness of the metal oxide nanoparticle layer to which the primary dye is adsorbed. Method of manufacturing dye-sensitized solar cell. The method of claim 1, wherein the method comprises the steps of manufacturing the photoelectrode, the metal oxide nanoparticle layer has a dye layer of two or more laminated structure having a different wavelength,
After adsorbing the secondary dye, in the metal oxide nanoparticle layer adsorbed with the secondary dye using a viscous basic desorbent, only the secondary dye of the portion located upward is desorbed,
Further comprising repeating one or more times to form a dye layer by adsorbing a tertiary dye having a different wavelength from the primary and secondary dyes used in the photoelectrode production to the desorption site of the secondary dye. Method for producing a dye-sensitized solar cell. The method of claim 1, wherein the metal oxide nanoparticle layer prior to adsorbing the dye is a metal oxide nanoparticle paste containing a metal oxide nanoparticle, a binder resin and a solvent having an average particle diameter of 1nm to 80nm on the blocking layer and heat treatment Forming, to form a dye-sensitized solar cell. The dye-sensitized method of claim 1, wherein the light scattering layer is formed by applying a metal oxide nanoparticle paste including a metal oxide nanoparticle having an average particle diameter of 100 nm to 2000 nm, a binder resin, and a solvent on the metal oxide nanoparticle layer and performing heat treatment. Manufacturing method of solar cell. The method of claim 1, wherein the blocking layer is formed by spin coating a metal oxide precursor or a metal oxide nanoparticle solution on one surface of a transparent conductive substrate. The method of claim 7, wherein the heat treatment is performed for 10 to 120 minutes at 400 to 550 ℃. After forming a metal oxide nanoparticle layer having a laminated structure of two or more layers of the same or different type on one surface of the transparent conductive substrate having a blocking layer, and forming a light scattering layer on the metal oxide nanoparticle layer, titanium tetrachloride (TiCl ₄ ) treatment is performed. Proceeding;
Adsorbing a primary dye onto at least two metal oxide nanoparticle layers formed on the transparent conductive substrate;
Primary of at least one layer of the metal oxide nanoparticle layer of the two or more layers of metal oxide nanoparticle layers in which the primary dye is adsorbed, using a viscous basic desorbent having a viscosity of 20 cps to 1500 cps. Desorbing only the dye;
By adsorbing secondary dyes having different wavelengths from the primary dyes to the site where only the primary dyes are desorbed, two or more metal oxide nanoparticle layers having a dye layer having a laminated structure having different wavelengths and a light scattering layer formed thereon Manufacturing a photoelectrode having;
Manufacturing a counter electrode by forming a platinum layer on one surface of the transparent conductive substrate; And
Disposing the photoelectrode and the counter electrode and filling an electrolyte
Including;
The TiCl ₄ treatment method includes immersing the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution having a concentration of 0.02 to 0.2 mol at 20 ° C. to 80 ° C. for 20 minutes to 20 hours.
The viscous basic desorption solution is a method for producing a dye-sensitized solar cell using a mixed solution of tetrabutylammonium hydroxide aqueous solution and a viscous polymer dissolved in a water-soluble solvent of water or ethanol. The method of claim 10, wherein the TiCl ₄ treatment method comprises immersing the substrate on which the metal oxide nanoparticle layer and the light scattering layer are formed in a TiCl ₄ aqueous solution having a concentration of 0.03 to 0.06 molar at 50 ° C. to 80 ° C. for 20 minutes to 1 hour. Method for producing a dye-sensitized solar cell. The method of claim 10, wherein the viscous polymer is polypropylene glycol, polyurethane, polyethylene oxide, polypropylene oxide, polyethylene glycol, chitosan, chitin, polyacrylamide, polyvinyl alcohol, polyacrylic acid, cellulose, ethyl cellulose, polyhydroxy Ethyl methacrylic acid, polyethylene, polypropylene, polyethylene naphthalate and polyethylene terephthalate selected from the group consisting of at least one, manufacturing method of dye-sensitized solar cell. The method of claim 10, wherein the manufacturing of the photoelectrode comprises: a metal oxide nanoparticle layer having a dye layer having two or more laminated structures having different wavelengths.
After adsorbing the secondary dye, desorbed only the secondary dye of at least one or more layers of the metal oxide nanoparticle layer in the upper portion of the metal oxide nanoparticle layer adsorbed with the secondary dye using a viscous basic desorbent. and,
The method may further include repeating one or more steps of adsorbing a third dye having a wavelength different from that of the first and second dyes used in manufacturing the photoelectrode to a desorption site of the second dye to further form a dye layer. , Manufacturing method of dye-sensitized solar cell. The method of claim 10, wherein the metal oxide nanoparticle layer of the laminated structure of two or more layers before adsorbing the dye,
The first and second metal oxide nanoparticle pastes containing the same or different kinds of metal oxide nanoparticles are sequentially applied on a blocking layer formed on a transparent conductive substrate and heat treated to sequentially form a metal oxide nanoparticle layer having a double stacked structure. Or
It is formed by repeating one or more steps of applying and heat-treating the metal oxide nanoparticle layer of the double layered structure using one or more metal oxide nanoparticle pastes that are the same as or different from the first and second metal oxide nanoparticle pastes. Method of manufacturing a dye-sensitized solar cell. The dye-sensitized method of claim 10, wherein the light scattering layer is formed by applying a metal oxide nanoparticle paste, a binder resin, and a solvent including metal oxide nanoparticles having an average particle diameter of 100 nm to 2000 nm on the metal oxide nanoparticle layer and performing heat treatment. Manufacturing method of solar cell. The method of claim 10, wherein the blocking layer is formed by spin coating a metal oxide precursor or a metal oxide nanoparticle solution on one surface of a transparent conductive substrate. The method of claim 15, wherein the heat treatment is performed at 400 to 550 ° C. for 10 to 120 minutes. Prepared by the method of claim 1,
A photoelectrode formed on the transparent conductive substrate and including a metal oxide nanoparticle layer and a light scattering layer to which dye is adsorbed,
A counter electrode disposed opposite the photoelectrode and including a platinum layer formed on a transparent conductive substrate;
An electrolyte filling between the photoelectrode and the counter electrode,
The dye-adsorbed metal oxide nanoparticle layer is a dye-sensitized solar cell having a multi-layered dye, comprising a dye layer of two or more laminated structures each of two or more dyes having different wavelengths are adsorbed. The method of claim 18, wherein the dye is adsorbed metal oxide nanoparticle layer,
In the metal oxide nanoparticle layer formed of one layer, two or more dyes having different wavelengths are adsorbed in a stacked structure, or
2 or more dyes having different wavelengths in the metal oxide nanoparticle layer formed of two or more layers are adsorbed separately to each layer to have two or more layers of dye-sensitized solar cell. The dye-sensitized solar cell of claim 18, wherein the dye-adsorbed metal oxide nanoparticle layer comprises a dye selected from the group consisting of metal complexes, inorganic dyes, and organic dyes. The method of claim 20, wherein the dye-adsorbed metal oxide nanoparticle layer is
A dye-sensitized solar cell further comprising a dye selected from the group consisting of metal complexes, inorganic dyes and organic dyes, and dyes having the same or different wavelengths. 19. The method of claim 18, wherein the metal oxide nanoparticles in the nanoparticle layer of the metal oxide on which the dye is adsorbed have an average particle diameter of 1nm to 80nm, titanium (Ti) oxide, zirconium (Zr) oxide, strontium (Sr) oxide, zinc ( Zn) oxide, indium (In) oxide, lanthanum (La) oxide, vanadium (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, tin (Sn) oxide, niobium (Nb) oxide, Magnesium (Mg) oxide, aluminum (Al) oxide, yttrium (Y) oxide, scandium (Sc) oxide, samarium (Sm) oxide, gallium (Ga) oxide, and strontium titanium (SrTi) oxide selected from the group consisting of A dye-sensitized solar cell comprising one or more kinds of metal oxides of the same or different kind. The method of claim 18, wherein the light scattering layer has an average particle diameter of 100nm to 2000nm, titanium (Ti) oxide, zirconium (Zr) oxide, strontium (Sr) oxide, zinc (Zn) oxide, indium (In) oxide, lanthanum (La) oxide, vanadium (V) oxide, molybdenum (Mo) oxide, tungsten (W) oxide, tin (Sn) oxide, niobium (Nb) oxide, magnesium (Mg) oxide, aluminum (Al) oxide, Dye-sensitized solar cell, comprising at least one metal oxide selected from the group consisting of yttrium (Y) oxide, scandium (Sc) oxide, samarium (Sm) oxide, gallium (Ga) oxide, and strontium titanium (SrTi) oxide . 19. The method of claim 18,
The dye-sensitized metal oxide nanoparticle layer has a thickness of 2μm to 50μm, dye-sensitized solar cell. The dye-sensitized solar cell of claim 18, wherein the light scattering layer has a thickness of 2 μm to 10 μm.

Images