KR101476743B1 - Method for manufacturing dye sensitized solar cells and dye sensitized solar cells manufactured by the same - Google Patents

Abstract

The present invention relates to a technology capable of improving efficiency of a dye-sensitized solar cell while at the same time remarkably reducing the dye-absorption time of a photoelectrode by mixing low price anion surfactants such as aerosol OT or the like, in dye-absorption solution. A method for manufacturing a dye-sensitized solar cell according to the present invention includes the steps of: forming a photoelectrode on a first substrate; forming a reduction electrode on a second substrate; and bonding the first substrate and the second substrate by making the photoelectrode and the reduction electrode face each other, and injecting an electrolyte therebetween. To absorb the dye in metal oxide particles to form the photoelectode, the dye is absorbed by being dipped in dye solution including an ion replacement to replace relative ion included in the dye with an ion lighter than the relative ion.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dye-sensitized solar cell and a dye-sensitized solar cell produced by the method. BACKGROUND ART < RTI ID = 0.0 >

TECHNICAL FIELD The present invention relates to a solar cell for converting solar energy into electric energy, and more particularly, to a dye-sensitized solar cell which absorbs a dye by adsorbing a dye by mixing an inexpensive anionic surfactant such as aerosol, The present invention relates to a technique capable of greatly reducing the time and increasing the efficiency of a dye-sensitized solar cell.

In the dye-sensitized solar cell, an exciton is formed when light is incident on a nanoparticle semiconductor oxide electrode in which dye molecules are chemically adsorbed, and a solar cell using a principle in which double electrons are injected into a conduction band of a semiconductor oxide to generate electric current to be.

In general, a dye-sensitized solar cell is formed by forming a film of an electrode material made of semiconductor nanocrystals having a large band gap energy capable of adsorbing a dye on a conductive substrate (glass, plastic or metal), adsorbing the dye on the surface of the film A counter electrode is disposed and an electrolyte is injected between both electrodes.

In the early days, dyes such as cis-dithiocyanatobis (2,2-bipyridine-4,4-dicarboxylate) ruthenium (II) dyes were mainly used as the dyes. However, in recent years, dyes constituting N3 dyes Bis (tetrabutylammonium) cis- dithiocyanatobis (2, 3, 4, 5, 6, 7) having anionic dicarboxylate anionic groups having tetrabutylammonium (TBA) counterions instead of dicarboxylic acid groups, 2-bipyridine-4-COOH, 4-COO - a) ruthenium (II)] dye is mainly used.

However, when the N3 dye is used for about 3 hours, the dye adsorption to the electrode made of the semiconductor nanocrystal is completed, whereas for the N719 dye, a long time is required for 20 hours or more before the dye adsorption is completed.

Despite this long process time, the reason why N719 dye is more widely used than N3 dye is because it has higher open-circuit voltage ( V _oc ) than N3 dye. It is known that the open-circuit voltage of a dye-sensitized solar cell is determined by the proton concentration at the interface between the electrode and the electrolyte. Since the N719 dye molecule provides less proton than the N3 dye, a small amount of proton is combined with a bidentate anionic oxygen atom (O ^2- ) on the surface of titanium oxide (TiO ₂ ) to form the end energy level of the TiO ₂ conduction band the level of the conduction-band edge shifts to the negative potential, which results in an increase in the open-circuit voltage.

On the other hand, in order to increase the adsorption rate of dyes, the following patent documents disclose a method for manufacturing a dye-sensitized solar cell, comprising a first step of forming a titanium oxide layer by applying a porous nanoparticle oxide on a first substrate on which a first conductive layer is formed, A third step of allowing the dye molecule solution to flow into the dye adsorption tank and adsorbing dye molecules on the titanium oxide layer in an environment of a temperature of 40 to 80 ° C and a vortex flow of 200 to 800 rpm; A fourth step of bonding the first substrate with a second substrate comprising a second conductive layer and a platinum layer, and a fifth step of providing an electrolyte between the first substrate and the second substrate. A manufacturing method of a battery is disclosed. That is, the dye is adsorbed in a vortex environment. According to this method, although the adsorption rate of the N719 dye can be increased, there is a limit to increase the efficiency of the solar cell.

Further, in order to increase the dye adsorption rate, a method of applying thermal or electrical energy may be used. However, when such a method is used, there arises a problem that the dye molecules easily aggregate to deteriorate the efficiency of the solar cell.

Korean Patent Laid-Open Publication No. 2013-0090430

The present invention provides a method of manufacturing a dye-sensitized solar cell capable of shortening a long process time required for manufacturing a conventional photo-electrode and improving the efficiency of a solar cell by improving the aggregation of dyes generated in a dye adsorption process .

According to an aspect of the present invention, there is provided a method of manufacturing a photoelectric conversion device, comprising: forming a photoelectrode on a first substrate; forming a reduction electrode on a second substrate; And injecting an electrolyte therebetween. The dye-sensitized solar cell according to claim 1, wherein in adsorbing the dye to the metal oxide particles forming the photo-electrode, Wherein the dye is immersed in a dye solution containing an ion exchanger capable of exchanging light ions with light ions compared to the counter ions, thereby adsorbing the dye.

The dye may comprise TBA (tetrabutylammonium).

The first substrate or the second substrate may be formed of glass, polyethyleneterephthalate, polyethylene naphthalate, polycarbonate, polypropylene, polyimide, triacetylcellulose ).

The photoelectrode may include a light absorbing layer and a light scattering layer.

The reducing electrode may include a transparent conductive electrode formed on the second substrate and a catalyst layer formed on the conductive electrode.

The dye may comprise N719.

The ion exchanger may comprise aerosol OT (sodium bis (2-ethylhexyl) sulfosuccinate).

The metal oxide may be at least one selected from the group consisting of TiO ₂ , SnO ₂ , WO ₃ , ZnO, SiO ₂ , ZrO ₂ , MgO, SrTiO ₃ , Al ₂ O _3,

The transparent conductive electrode may include ITO, FTO, ATO, ZnO, SnO ₂ , ZnO ₂ O _3, and ZnO-Al ₂ O ₃ .

The catalyst layer may be formed of Pt, Ru, Pd. Ir, Rh, Os, C, WO _3, and TiO ₂ .

The manufacturing of the photoelectrode includes the steps of forming a light absorbing layer on the first substrate, forming a light scattering layer on the light absorbing layer, dissolving N719 dye and aerosol ottion in the solvent on the light absorbing layer and the light scattering layer And then the dye is washed by washing and drying the photoelectrode to which the N719 dye is adsorbed.

The solvent may comprise ethanol.

The concentration of N719 may be 0.5 mM or more.

The concentration of the aerosol may be 0.3 to 0.6 mM.

The present invention also provides a dye-sensitized solar cell produced by the above-described method.

The method of manufacturing a dye-sensitized solar cell according to the present invention can achieve the following effects.

According to the present invention, since the dye liquid contains a surfactant capable of ion exchange with heavy TBA which is a counter ion of N719 dye molecule and having a light cation as a counter ion, the dye adsorption time of the N719 dye molecule can be shortened .

In addition, the ion-exchanged N719 dye molecules reduce the aggregation phenomenon and reduce the recombination of charges that may occur at the interface between the electrolyte and the titanium oxide, thereby improving the photoelectric conversion efficiency of the dye-sensitized solar cell.

FIG. 1A shows the adsorption rate of N719 dye according to N719 dye concentration.
FIG. 1B shows the adsorption rate of N719 dye according to the concentration of aerosol in the N719 dye solution.
FIG. 2 shows the absorbance of the photoelectrodes (Film A) adsorbing N719 dye to 20 nm-sized titanium oxide particles and the absorbance of the photoelectrodes (Film B) adsorbing N719 dye by applying aerosol otion over time.
3A shows the amount of dye adsorbed on titanium oxide according to the dye adsorption temperature.
FIG. 3B illustrates the result of FIG. 3A by using the Arrhenius equation to obtain the activation energy.
Fig. 4 is a graph showing the adsorption amount of N3 dye according to the dye adsorption time of the photoelectrode (Film A) adsorbing N3 dye to 20 nm size titanium oxide particles and the photo electrode (Film B) adsorbing N3 dye by applying aerosol .
FIG. 5 is a graph showing the change of intermolecular binding energy in the dye solution used in the dye adsorption of the photoelectrodes by using X-ray photonelectron spectroscopy (XPS, K-alpha (Thermo VG, UK) .
FIG. 6 shows the results of Fourier transform infrared (FTIR) using attenuated total reflectance (ATR) to determine the degree of dye aggregation at the photoelectrode.
FIG. 7 is a graph showing the results of measurement of a photo-electrode (Film B) adsorbing N719 dye by applying a photo-electrode (Film A) adsorbing N719 dye to a 20 nm-sized titanium oxide particle and aerosol otion and distilled water (1 ml) For 10 minutes.
8 is a graph showing the photocurrent-light voltage curves and photoelectric conversion efficiency characteristics of the dye-sensitized solar cell according to the present invention with a solar simulator (Newport, Oriel class A, 92251A) under the conditions of 1 Sun (AM 1.5, 100 mW / cm ² ) And the results are shown in Fig.
9A is a graph showing a result of measuring a recombination resistance (Rct) between an electrode and an electrolyte in a second semicircle of the low frequency region of the Nyquist line.
Figure 9b shows the result obtained the recombination lifetime (recombination lifetime, τ _r) by using a pick-frequency of the low-frequency region (<10 ² Hz) of the phase board lead.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. Also, when a part is referred to as "including " an element, it does not exclude other elements unless specifically stated otherwise.

The present inventors have studied a dye adsorption method which can improve the photoelectric conversion efficiency by reducing the adsorption time of the N719 dye, which is excellent in photoelectric conversion efficiency but takes a long time for dye adsorption, and reduces aggregation of the dye. The results are as follows.

Since the TBA (tetrabutylammonium) forming the counter ion in the N719 dye is heavy, the migration to the titanium oxide is not smooth and the adsorption rate of the dye is decreased.

Since an ion exchanger tends to bond with ions having a higher polarizability, an ion exchanger having a cation having a lower polarization ratio than TBA ⁺ of N719 dye as a counter ion is added to the N719 dye The ion exchanger tries to bond with TBA ⁺ , the N719 dye accepts the cation of the ion exchanger as a counter ion by charge compensation, and the ion exchanger having a light cation as compared with TBA ⁺ like Na ⁺ When incorporated into the N719 dye, the N719 dye accepts the light cation of the ion exchanger, which can increase the migration rate of the N719 dye and increase the dye adsorption rate.

As a result, in the case of cation-exchanged dyes, since the electron injection efficiency of the conduction path of titanium oxide is increased and the surface area of titanium oxide exposed to the electrolyte is reduced, the electrons existing in the conduction band of titanium oxide and the tree The recombination with the iodine ion (I ₃ ^- ) can be suppressed, and the efficiency of the solar cell can also be improved.

According to another aspect of the present invention, there is provided a method of fabricating a dye-sensitized solar cell, comprising: forming a photoelectrode on a first substrate; forming a reduction electrode on a second substrate; The first substrate and the second substrate are bonded to each other, and an electrolyte is injected therebetween to produce a dye-sensitized solar cell. The dye containing TBA (tetrabutylammonium) is adsorbed on the metal oxide particles forming the photo- , An ion exchanger having a cation that is lighter than the TBA is adsorbed on the dye.

The first substrate may be formed of a transparent material so as to allow external light to be incident thereon, and may be made of a glass or a polymeric material. The polymeric material may include, for example, poly (ethylene terephthalate) polyethyleneterephthalate (PET), polyethylenenaphthalate (PEN), polycarbonate (PC), polypropylene (PP), polyimide (PI) and triacetylcellulose .

The photoelectrode may include a light absorbing layer made of a transparent metal oxide. In addition, the optical electrode may further include a light scattering layer formed on the light absorption layer.

The transparent surface of the metal oxide particles to absorb the external light is absorbed the dye containing TBA (tetrabutylammonium) for generating excited electrons, as the metal oxide is TiO _2, SnO _2, WO _3, ZnO, SiO _2, ZrO ₂ , MgO, SrTiO ₃ , Al ₂ O _3, or a composite thereof. At this time, the thickness of the photoelectrode is preferably 1 mu m to 30 mu m.

The second substrate disposed opposite to the first substrate serves as a support for supporting the reducing electrode, and may be formed in a transparent manner, and may be formed of the same material as the first substrate.

The reducing electrode may include a transparent electrode formed on the second substrate and a catalyst electrode formed on the transparent electrode. The transparent electrode may include ITO, FTO, ATO, ZnO, SnO ₂ , ZnO ₂ O ₃ , ZnO- Al ₂ O _3, and the like. In addition, the catalyst electrode serves to activate a redox couple, and Pt, Ru, Pd. Ir, Rh, Os, C, WO ₃ , TiO ₂ , and the like.

And a ^{dye, wherein} the dye N719 [ruthenium (II) bis ( tetrabutylammonium) cis -dithiocyanatobis (2,2-bi pyridine-4-COOH, 4-COO)].

The ion exchanger may be any one that is capable of being ion-exchanged with TBA constituting the N719 dye and having a lighter ion than TBA, but in particular, aerosol OT, sodium bis (2-ethylhexyl) sulfosuccinate, , The ion exchange with TBA at a low cost is preferable because it is very light as sodium (Na).

Hereinafter, a method of manufacturing a dye-sensitized solar cell according to the present invention will be described in detail.

[Example]

Photoelectrode manufacturing process

First, a photo electrode was formed on a transparent glass substrate by a screen printing process using commercially available titanium oxide paste for screen printing.

Specifically, a TiO ₂ paste having an average particle size of 20 nm for dye adsorption was applied through a screen printing process so as to have a film thickness of 12 μm, and heat treatment was performed at 500 ° C. for 30 minutes using a box furnace The polymer binder and the solvent were removed to form a light absorbing layer.

Then, a TiO ₂ paste having an average particle size of 400 nm was applied through a screen printing process so as to have a thickness of 6 μm, and then heat treatment was performed at 500 ° C. for 30 minutes using a box furnace to remove the polymer binder and solvent Thereby forming a light scattering layer.

The surface modification of the photoelectrode, in which the light absorbing layer and the light scattering layer were laminated, was performed using a known surface modification method. Specifically, 40 mM of titanium tetrachloride (TiCl ₄ ) was immersed in a container diluted with an aqueous solution to prevent impurities such as Fe in the electrode and recombination that may occur on the titanium oxide surface to some extent. For 30 minutes, and the electrodes were washed and dried using distilled water and anhydrous ethanol. Then, a heat treatment was performed at 500 ° C. for 30 minutes using a box furnace.

Dye adsorption process

The dye used in the solar cell according to the embodiment of the present invention is an N719 dye. In the dye adsorption process according to the embodiment of the present invention, aerosol OT (sodium bis (2-ethylhexyl) sulfosuccinate) is added to the N719 dye as an ion exchanger to perform the dye adsorption process.

In order to evaluate the optimum concentration of aerosol water contained in the N719 dye and the ion exchanger, the adsorption rate of the N719 dye according to the concentration of the N719 dye adsorbed on the photoelectrode prepared according to the embodiment of the present invention and the concentration of the aerosol And the results were as shown in Figs. 1A and 1B. At this time, the dye adsorption amount of the photo-electrodes was calculated by measuring the absorbance of the dye desorbed from each of the electrodes using UV-Vis spectroscopy (Optizen POP spectrophotometer).

Specifically, FIG. 1A shows the amount of dye adsorbed on the surface of titanium oxide according to the concentration of N719 dye during the same adsorption time, and it is shown that the N719 dye can be sufficiently adsorbed when the adsorption time is more than 0.5 mM. In addition, FIG. 1B shows the amount of dye adsorbed on the surface of titanium oxide according to the concentration of aerosol in the same adsorption time. When the concentration is 0.3 to 0.6 mM, the dye is adsorbed sufficiently.

From these results, in the example of the present invention, a dye solution in which aerosol is added at a concentration of 0.3 mM to an N719 dye solution diluted to a concentration of 0.5 mM in anhydrous ethanol was prepared.

The photoelectrode was immersed in the thus prepared dye solution for a predetermined time to allow the dye to be adsorbed. The dye-adsorbed photoelectrode was washed with ethanol and dried at room temperature to prepare a photoelectrode.

Electrolyte injection process

A glass substrate coated with FTO as the photoelectrode and the counter electrode as a counter electrode was prepared and masked by using an adhesive tape on the conductive side of the substrate and then H ₂ PtCl ₆ solution was dropped thereon dropwise, dried on a hot plate heated to 100 ° C, and heat-treated at 500 ° C for 30 minutes in a box furnace to form a catalyst electrode, thereby preparing a relative reduction electrode.

A fine hole having a diameter of about 0.75 mm was formed on the relative reduction electrode using an electric drill equipped with a diamond tip.

Then, the photoelectrode and the relative reduction electrode are disposed so as to face the conductive surface, and the two electrodes are bonded using a thermosetting polymer material, Surlyn (Meltonix 1170-60, Solaronix). The two electrodes can be bonded together by holding them in an oven set at a temperature of about 120 ° C for about 2 minutes while being fixed using a forceps.

After bonding the photoelectrode and the counter electrode, the electrolyte is injected into the space between the two electrodes through the micropores formed in the counter electrode. The electrolyte was prepared by dissolving 1-butyl-3-methyl-imidazolium iodide in a solvent in which the volume ratio of acetonitrile and valeronitrile was 85:15, BMII) is 0.7M, iodine (I ₂₎ is 0.03M, guanidyl Stadium thiocyanate (guanidinium thiocyanate, GSCN) is 0.1M, 4- tert-butyl-pyridine is diluted to a (4-tert-butylpyridine) 0.5M Respectively. After the electrolyte was filled, the thermosetting material, Surlyn, was covered with pores and the cover glass was placed thereon, and the solder paste was melted to bond the cover glass and the photoelectrode. Through this process, it is possible to prevent the problem that the electrolyte is volatilized and lost.

Meanwhile, since the relative reduction electrode and the electrolyte according to the present invention are manufactured by a conventional method, they are not particularly limited to the embodiment of the present invention.

[Comparative Example]

For comparison with a solar cell manufactured according to an embodiment of the present invention, a photoelectrode was prepared by using only the N719 dye liquid diluted to a concentration of 0.5 mM in anhydrous ethanol without adding aerosol water to the dye adsorption process, The other steps were carried out in the same manner as in the example of the present invention to prepare a dye-sensitized solar cell.

The absorbances of the two types of dye-sensitized solar cells fabricated as described above were compared. FIG. 2 shows the absorbance of the photoelectrodes (Film A) adsorbing N719 dye to 20 nm-sized titanium oxide particles and the absorbance of the photoelectrodes (Film B) adsorbing N719 dye by applying aerosol otion over time.

As shown in FIG. 2, it can be seen that the absorbance of the dye-adsorbed photoelectrode in the N719 dye solution for about 19 hours was about the same as that of the photoelectrode adsorbed for about 10 hours by adding the dye to the N719 dye solution. This means that the addition of aerosol otion to the N719 dye solution almost doubles the dye adsorption rate.

FIG. 3A shows the amount of dye adsorbed to titanium oxide according to the dye adsorption temperature, and the activation energy can be obtained through FIG. 3B which is schematized using the Arrhenius equation. 3B, the activation energy of the photoelectrode (Film A) adsorbing the N719 dye to the 20 nm-sized titanium oxide particles was 7.8 kJ mol ^-1 , the activation energy of the photo-electrode (Film B) adsorbed on the N719 dye by applying aerosol Is 5.3 kJ mol &lt; ^{-1 &} gt ;. The 32% reduced activation energy of the photoelectrode (Film B) adsorbing the N719 dye by applying aerosol otion supports the fast dye adsorption observed in FIG.

Fig. 4 is a graph showing the adsorption amount of N3 dye according to the dye adsorption time of the photoelectrode (Film A) adsorbing N3 dye to 20 nm size titanium oxide particles and the photo electrode (Film B) adsorbing N3 dye by applying aerosol Show.

As shown in FIG. 4, when the N3 dye having no counter ion is used, there is almost no difference in the amount of dye adsorption depending on the adsorption time of the dye depending on whether the aerosol is used or not, This means that it only affects the adsorption rate of N719 dye with counter ion rather than N3.

X-ray photoelectron spectroscopy (XPS, K-alpha (Thermo VG, UK)) was used to observe the intermolecular binding energy change in the dye solution used in the dye adsorption of the photoelectrodes And the results are shown in FIGS. 5A and 5B.

5A and 5B are XPS spectra of N1s and O1s of dye solution (AOT / N719) to which aerosol is added to N719 dye solution and N719 dye solution, respectively. Figure 5a is the N1s spectrum associated with nitrogen in the NCS group, terpyridine / bipyridine ligand, and TBA ⁺ that make up the N719 dye molecule. As the aerosol is added, the TBA ⁺ peak is increased by 0.2 eV And moved to binding energy. Figure 5b shows the O1s spectrum associated with a carboxy (COO ^- group) group comprising the N719 dye molecule, with the addition of aerosol, the peak shifted to a binding energy of 0.2 eV lower. These XPS results indicate that the chemical environment around the carboxy group of the N719 dye molecule and the counter ion, TBA ⁺ , significantly changed due to the addition of aerosol.

In general, the ion exchanger tends to associate with ions having a higher polarizability, so from the absorbance results of the N719 dye of Figure 2 and the XPS results of Figure 5, Since the sulfate group (SO ₃ ^- group) of aerosol otion tries to bind further with TBA ⁺ , the counter ion of N719 dye, which has higher polarizability than the counter ion sodium ion, ion exchange between aerosol and N719 dye Can be inferred.

Fourier transform infrared spectroscopy (FTIR) using attenuated total reflectance (ATR) was used to grasp the degree of dye aggregation at the photoelectrode. The results are shown in FIG. 6 .

The proportion of dye molecules that are weakly bound to the TiO ₂ surface can be predicted by comparing the intensities of the two peaks. Two peaks are the carboxylic acid group (COOH group, 1375 cm ^-1 stretching mode) chemically bonded to the TiO ₂ surface and the carboxylic acid group (1715 cm ^-1 C = O band) of the weakly physically adsorbed dye molecules. The calculated value shows the degree of dye aggregation.

The degree of aggregation of the dye calculated from FIG. 6A was about 23.1% for the photoelectrode (Film A) in which the N719 dye was adsorbed on the titanium oxide particle having the size of 20 nm, and the photoelectrode (Film B) on which the N719 dye was adsorbed by applying aerosol Is about 17.9%. That is, when the aerosol is introduced, the degree of dye aggregation is reduced. In addition, symmetric stretching mode (S = O stretching mode) of S = O, which is mainly observed in aerosol components of both electrodes, was not observed. This shows that the two electrodes are thoroughly cleaned and no aerosol components remain. FIG. 6B shows the intensity of the CH stretching band of the TBA + counter ion of the N719 dye. As a result, the intensity of the CH stretching band was decreased as a result of the addition of the aerosol, which is attributed to the ion exchange by the aerosol Seems to have done.

FIG. 7 is a graph showing the relationship between the photoelectrode (film A) adsorbing N719 dye on a 20 nm-sized titanium oxide particle and the photo-electrode (Film B) adsorbing N719 dye by applying aerosol otium to 1 mM potassium hydroxide (KOH) Of distilled water for 10 minutes. It can be seen that when the aerosol is applied, the desorption of the dye is less, which means that when the aerosol contains the aerosol, the aggregation of the dye decreases.

Then, the dye-sensitized solar cell of the photoelectric current in accordance with the present invention an optical voltage curve and the photoelectric conversion efficiency characteristics are 1 Sun (AM1.5, 100mW / cm 2) solar simulator conditions (Newport, Oriel class A, 92251A) in the The results are shown in FIG. 8 and Table 1 below.

Sample V _oc (mV) J _sc (mA / cm ² ) FF 侶 (%) Devicee 802 ± 0.25 13.7 ± 0.11 0.66 ± 0.01 7.3 ± 0.09 Device A * 796 ± 0.39 15.8 ± 0.19 0.67 ± 0.02 8.4 ± 0.11 Device B 820 ± 0.12 15.2 ± 0.15 0.66 ± 0.01 8.1 ± 0.12 Device B * 817 ± 0.36 17.0 + - 0.23 0.66 ± 0.01 9.2 ± 0.08

Here, a device (device A) using a photoelectrode (N719 dye) adsorbed on a titanium oxide particle having a size of 20 nm for 19 hours and a device (Device B) using a photoelectrode having an N719 dye adsorbed for 10 hours by applying aerosol Are compared. In Table 1, Device A * and Device B * are electrodes using an electrode in which a titanium oxide scattering layer having a size of 400 nm is further laminated.

Cells using photoelectrodes with N719 dye adsorption (Device A and Device A *) showed efficiencies of 7.3% and 8.4%, respectively, while those using photoelectrodes with N719 dye adsorbed using aerosol (Device B and Device B *) can achieve high efficiency of 8.1% and 9.1%, respectively.

FIG. 8B shows the efficiency change of the cells with respect to time and shows a certain stability regardless of addition of aerosol. The electrochemical impedance spectroscopy (EIS) of the dye-sensitized solar cell according to the present invention was measured using an impedance analyzer (BioLogic, SP-300) in the frequency range of 10 ^-1 to 10 ⁶ Hz And analyzed using the Z-view software. FIG. 9 shows the Nyquist plot and the Bode-phase plot.

The second semicircle of the low frequency region of the Nyquist plot of FIG. 9A means the recombination resistance (Rct) between the electrode and the electrolyte. The titanium oxide particle having a size of 20 nm was irradiated with a N719 dye for 19 hours, (Device A) was 15.2 ohm, and the cell using the photoelectrode (Device B), in which the N719 dye was adsorbed for 10 hours by applying aerosol, was 18.5 ohm.

Using the pick frequency of the low frequency region (<10 ² Hz) of the board phase diagram of FIG. 9B, the recombination lifetime (τ _r ) can be obtained. It can be seen that the addition of aerosol oat increases the recombination resistance and recombination life. This is related to the clustering of the dyes described above. Due to the addition of aerosol, the surface of titanium oxide exposed to the electrolyte decreases as the degree of dye aggregation decreases, and recombination is suppressed.

From the above results, it can be seen that, when the low-cost anionic surfactant, aerosol, is incorporated into the dye liquid according to the method of the present invention, the rate of dye adsorption on the titanium oxide surface is accelerated, The degree of aggregation can be improved, and the manufacturing cost of the solar cell can be reduced and the photoelectric conversion efficiency can be improved.

Claims (15)

Forming a photo-electrode on the first substrate,
Forming a reducing electrode on the second substrate;
The method of manufacturing a dye-sensitized solar cell according to claim 1, further comprising the steps of: bonding the first substrate and the second substrate to each other by opposing the photo-electrode and the reduction electrode; and injecting an electrolyte therebetween,
The dye is immersed in a dye solution containing an ion exchanger capable of exchanging counter ions contained in the dye with light ions in comparison with the counter ions in adsorbing the dye to the metal oxide particles forming the photo electrode, Wherein the dye-sensitized solar cell comprises a dye-sensitized solar cell. The method according to claim 1,
Wherein the dye is a dye containing tetrabutylammonium (TBA). The method according to claim 1,
The first substrate or the second substrate may be formed of glass, polyethyleneterephthalate, polyethylene naphthalate, polycarbonate, polypropylene, polyimide, triacetylcellulose, Wherein the dye-sensitized solar cell comprises a dye-sensitized solar cell. The method according to claim 1,
Wherein the photoelectrode comprises a light absorbing layer and a light scattering layer. The method according to claim 1,
Wherein the reducing electrode comprises a transparent conductive electrode formed on the second substrate and a catalyst layer formed on the conductive electrode. The method according to claim 1,
Wherein the dye comprises N719. The method according to claim 1,
Wherein the ion exchanger comprises aerosol OT (sodium bis (2-ethylhexyl) sulfosuccinate). The method according to claim 1,
Wherein the metal oxide is at least one selected from the group consisting of TiO ₂ , SnO ₂ , WO ₃ , ZnO, SiO ₂ , ZrO ₂ , MgO, SrTiO ₃ , Al ₂ O ₃ or a complex thereof. 6. The method of claim 5,
Wherein the transparent conductive electrode comprises ITO, FTO, ATO, ZnO, SnO ₂ , ZnO ₂ O ₃ and ZnO-Al ₂ O ₃ . 6. The method of claim 5,
The catalyst layer may be formed of Pt, Ru, Pd. Ir, Rh, Os, C, WO _3, and TiO ₂ . The method according to claim 1,
The photo-
Forming a light absorbing layer on the first substrate,
Forming a light scattering layer on the light absorbing layer,
Immersing the light absorbing layer and the light scattering layer in a dye solution obtained by dissolving N719 dye and aerosol dye in a solvent to adsorb the N719 dye,
And washing the photoelectrode where the dye absorbs the N719 dye, and drying the photoelectrode. 12. The method of claim 11,
Wherein the solvent is anhydrous ethanol. 12. The method of claim 11,
Wherein the concentration of N719 is 0.5 mM or more. 12. The method of claim 11,
Wherein the concentration of the aerosol is 0.3 to 0.6 mM. A dye-sensitized solar cell produced by the method according to any one of claims 1 to 14.

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