JP2010198758A - Dye-sensitized solar cell and electrode substrate with wiring used for it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent corrosion of current collector wiring in non-electric conduction state and conduction state to increase durability and to enable to perform stable power generation for a long period. <P>SOLUTION: The dye-sensitized solar cell 1 has a transparent electrode substrate 2 in which a transparent conductive film 2b is formed on one face of a transparent substrate 2a and a counter electrode substrate 3 which faces the transparent electrode substrate 2, and has an electrolyte layer 4 formed between the transparent electrode substrate 2 and the counter electrode substrate 3. The dye-sensitized solar cell 1 has a current collector wiring 5 formed on the transparent conductive film 2b, a wiring protection film 6 formed on the surface of the current collector wiring 5, and a shield film 7 which covers the surface of the wiring protection film 6 and shields chemically and electrically the current collector wiring 5 and the wiring protection film 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a dye-sensitized solar cell and an electrode substrate with wiring used therein.

  Conventionally, a solar cell is known as an element that converts light energy such as sunlight into electric energy. As the solar cell, a silicon solar cell using single crystal silicon, polycrystalline silicon, or amorphous silicon is known. Although silicon type solar cells have high photoelectric conversion efficiency, they have problems such as high energy consumption in the manufacturing process, high manufacturing cost, and low freedom of shape and color. Dye-sensitized solar cells are attracting attention as solar cells that can solve the problems of simple silicon solar cells.

  The dye-sensitized solar cell was devised by Michael Gretzzel of Switzerland, and has a thin-film electrode made of oxide semiconductor fine particles adsorbed with a dye and a counter electrode made of platinum or the like. It has a structure in which an electrolyte layer containing iodine ions is formed between the electrodes. Dye-sensitized solar cells do not require large-scale equipment like a semiconductor manufacturing apparatus, can be manufactured at low cost, are easily mass-produced, and have a high degree of freedom in color and shape.

  By the way, the thin film electrode constituting the dye-sensitized solar cell is formed by laminating a transparent conductive film made of ITO (tin-added indium oxide) on a transparent plate such as a glass plate. The resistance value is higher than that of a film made of metal. For this reason, it has been difficult to increase the photoelectric conversion efficiency of the dye-sensitized solar cell. Conventionally, a current collecting wiring (collecting wiring) made of a metal such as gold, silver, or copper is formed on a transparent conductive film. There was an idea to lower the resistance value.

  However, when the current collector wiring is formed on the transparent conductive film, the current collector wiring is exposed to the electrolyte layer at all times. Therefore, the current collector wiring corrodes due to a chemical reaction with iodine in the electrolyte layer. There was a problem that the function deteriorated.

  Therefore, conventionally, by forming a physical film such as a glass film or an oxide film on the surface of the current collector wiring, direct contact between the current collector wiring and the electrolyte layer is eliminated, thereby preventing the current collector wiring from corroding. The technique of preventing was known (for example, refer patent document 1, 2, 3).

JP 2008-192427 A JP 2003-297158 A JP 2006-286434 A

  If the current collector wiring is covered with, for example, a glass film, a dye-sensitized solar cell having such a structure is placed in a dark room so that power generation is not performed. Corrosion of the wiring can be prevented.

  However, when the energized state in which power is generated by irradiating sunlight or the like is left, there is a problem that a disconnection portion due to corrosion appears in the current collecting wiring after a certain period of time has passed. This is thought to be due to the following.

  When the current collector wiring is covered with, for example, a glass film, a chemical reaction occurs due to the components of the glass film and iodine ions in the electrolyte layer, but the reaction speed is extremely slow in a non-energized state. Therefore, if the non-energized state is set, corrosion of the current collector wiring can be prevented for a long period.

  However, when the energized state is generating electricity, the oxidation / reduction reaction of iodine ions in the electrolyte layer is repeated, so that the speed of the chemical reaction between the components of the glass film and the iodine ions in the electrolyte layer is accelerated. The reaction proceeds at a much faster rate than in the non-energized state. For this reason, it is considered that when the energized state is maintained, pinholes and cracks are generated in the glass film after a certain period of time has elapsed, and as a result, the current collecting wiring is corroded.

  Accordingly, the present invention has been made to solve the above-mentioned problems, and in a dye-sensitized solar cell and an electrode substrate with wiring used therein, the current collector wiring is prevented from corroding in a non-energized state and a conductive state, and is durable. The purpose is to improve the performance and enable stable power generation over a long period of time.

  In order to solve the above problems, the present invention includes a transparent electrode substrate having a transparent conductive film formed on one side of a transparent substrate, and a counter electrode substrate facing the transparent electrode substrate, A dye-sensitized solar cell in which an electrolyte layer is formed between a counter electrode substrate, a current collector wiring formed on a transparent conductive film, and a wire formed on the surface of the current collector wiring It is characterized by a dye-sensitized solar cell having a protective film and a shield film that covers the surface of the wiring protective film and shields the current collecting wiring and the wiring protective film chemically and electrically.

  In this dye-sensitized solar cell, the current collector wiring and the wiring protective film are chemically and electrically shielded by the shield film so that the current collector wiring and the wiring protective film do not cause a chemical reaction with the electrolyte layer. .

  Moreover, in the said dye-sensitized solar cell, it is preferable to further have the oxide semiconductor porous film which consists of oxide semiconductor fine particles by which the pigment | dye was adsorbed. In this dye-sensitized solar cell, power can be generated by such an oxide semiconductor porous film.

  Further, in the case of the dye-sensitized solar cell, the shield film is composed of an oxide semiconductor to which a dye is adsorbed, and the dye is densely formed on the surface layer portion of the oxide semiconductor on the counter electrode substrate side and porous to the oxide semiconductor. It is preferable to have a dye adsorbing structure that is adsorbed more than the surface layer portion on the counter electrode substrate side of the film.

  When the shield film has such a dye adsorption structure, the current collector wiring and the wiring protective film can be shielded chemically and electrically by the shield film.

Furthermore, in the case of the dye-sensitized solar cell, the shield film is preferably formed so as to cover the entire transparent conductive film.
With such a structure, a dye-sensitized solar cell can be easily manufactured.

  And in the case of the said dye-sensitized solar cell, the oxide semiconductor which comprises a shield film can have an amorphous structure which does not have a space | gap substantially inside.

  Furthermore, the shield film can have a dense structure composed of oxide semiconductor fine particles to which a dye is adsorbed and having an average particle diameter smaller than that of the oxide semiconductor porous film.

  In any of the above dye-sensitized solar cells, the shield film is preferably formed thinner than the current collecting wiring and the wiring protective film.

  By doing in this way, the situation where the adhesiveness of a wiring protective film and a shield film falls can be avoided.

  Furthermore, in any of the above dye-sensitized solar cells, the wiring protective film is preferably formed using alkali-free glass containing no alkali metal. By doing in this way, about a wiring protective film, a chemical reaction with an electrolyte layer can be made hard to occur.

  And this invention has a transparent electrode board | substrate with which the transparent conductive film is formed in the single side | surface of a transparent substrate, and a counter electrode board | substrate facing the transparent electrode board | substrate, A transparent electrode board | substrate and a counter electrode board | substrate An electrode substrate with wiring used for a dye-sensitized solar cell in which an electrolyte layer is formed between the transparent electrode substrate, a current collector wiring formed on the transparent conductive film, and a surface of the current collector wiring Provided is an electrode substrate with wiring having a wiring protective film formed thereon, and a shield film that covers the surface of the wiring protective film and shields the wiring protective film and the wiring protective film chemically and electrically.

  In the case of the above-mentioned electrode substrate with wiring, it is preferable to further have an oxide semiconductor porous film made of oxide semiconductor fine particles adsorbed with a dye.

  The shield film is composed of an oxide semiconductor to which a dye is adsorbed, and the dye is densely formed on the surface layer portion of the oxide semiconductor on the counter electrode substrate side and from the surface layer portion of the oxide semiconductor porous film on the counter electrode substrate side. It is preferable to have a dye adsorbing structure that is adsorbed in a large amount.

  As described above in detail, according to the present invention, in the dye-sensitized solar cell and the electrode substrate with wiring used therein, the corrosion of the current collecting wiring in the non-energized state and the energized state is prevented and the durability is improved. This makes it possible to generate power stably over a long period of time.

It is sectional drawing which shows typically the structure of the dye-sensitized solar cell which concerns on embodiment of this invention. Similarly, it is sectional drawing which shows a wiring protective film and a shield film. Similarly, it is sectional drawing which shows an oxide semiconductor porous film. Similarly, it is sectional drawing which shows typically the chemical reaction in an electrolyte layer with the behavior of an electron or a hole. It is sectional drawing which shows the current collection wiring and wiring protective film in which the shield film is not formed. (A) is a top view which shows the current collection wiring formed with the striped pattern, (b) is a top view which shows the current collection wiring formed with the grid | lattice pattern. It is sectional drawing which shows a current collection wiring, wiring protective film, and shield film when the shield film in which film thickness differs from FIG. 1 is formed. It is the figure which showed schematic structure of the light irradiation apparatus used by the comparative example. It is a figure which shows the result of a solar cell with a shield film, and shows an initial state. It is a figure which shows the result of the solar cell with a shield film, and shows the 31st day. It is a figure which shows the result of a solar cell without a shield film, and shows an initial state. It is a figure which shows the result of a solar cell without a shield film, and shows the 31st day. It is sectional drawing which shows typically the structure of the dye-sensitized solar cell which concerns on a modification. It is sectional drawing which shows typically the structure of the dye-sensitized solar cell which concerns on another modification.

  Hereinafter, embodiments of the present invention will be described. In addition, the same code | symbol is used for the same element and the overlapping description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view showing a configuration of a dye-sensitized solar cell 1 according to an embodiment of the present invention. As shown in FIG. 1, the dye-sensitized solar cell 1 includes a transparent electrode substrate 2 and a counter electrode substrate 3 facing the transparent electrode substrate 2, and includes a transparent electrode substrate 2 and a counter electrode substrate 3. An electrolyte layer 4 is formed therebetween. In addition, the dye-sensitized solar cell 1 includes a current collector wiring 5, a wiring protective film 6, a shield film 7, and an oxide semiconductor porous film 8.

  Among these, the electrode substrate 9 with wiring is comprised by the transparent electrode substrate 2, the current collection wiring 5, the wiring protective film 6, and the shield film 7. FIG. The electrode substrate with wiring 9 is used for the dye-sensitized solar cell 1, and the dye-sensitized solar cell 1 can be manufactured.

  The transparent electrode substrate 2 includes a transparent substrate 2a and a transparent conductive film 2b formed on the surface of the transparent substrate 2a on the counter electrode substrate 3 side.

  The transparent substrate 2a is a plate material using a transparent material such as glass or PET film, and has a thickness of about 0.7 mm to 3.0 mm. The transparent conductive film 2b is made of ITO (tin-added indium oxide), FTO (fluorine-added tin oxide), a mixture of ITO and ATO (antimony oxide), etc., and has a thickness of about 0.1 μm to 1 μm.

  The counter electrode substrate 3 includes an electrode substrate 3a and a catalyst film 3b formed on the surface of the electrode substrate 3a on the transparent electrode substrate 2 side. The electrode substrate 3a is a plate material using a conductive material such as titanium or nickel, and has a thickness of about 0.3 mm to 1.5 mm. The catalyst film 3b is a thin film obtained by evaporating platinum (Pt), carbon, rhodium, ruthenium or the like, and has a thickness of about 0.1 μm to 10 μm. In addition to the above, the counter electrode substrate 3 may be a glass substrate on which a transparent conductive film is formed.

  The electrolyte layer 4 is formed by sealing an electrolyte solution in a space secured between the transparent electrode substrate 2 and the counter electrode substrate 3. The electrolyte solution consists of a solvent, a redox couple and an additive. As the solvent, nitrile solvents (for example, acetonitrile, propionitrile, etc.), carbonate solvents (for example, ethylene carbonate, propylene carbonate, etc.), and ionic liquids (for example, dimethylpropylimidazolium iodide, etc.) can be used. As the redox couple, a cationic compound such as iodine / metal iodide compound, iodine / methylpropylimidazolium iodide, or an iodine / quaternary ammonium salt compound can be used. Furthermore, as the additive, a heterocyclic compound containing an N (nitrogen) atom (for example, pyridine, tertiary butyl pyridine, quinoline, acridine, etc.) can be used.

  The current collector wiring 5 is made of a metal having good conductivity such as gold, silver, copper, or platinum, and is formed on the transparent conductive film 2b. As shown in FIG. 6A, the current collecting wiring 5 has a striped pattern in which current collecting lines 5a formed on a straight line are regularly arranged at almost equal intervals. FIG. 1 shows two adjacent current collection lines 5 a constituting the current collection wiring 5. As shown in FIG. 6B, the current collecting wiring 5 can also be formed in a grid pattern by forming current collecting lines 5b that intersect the current collecting lines 5a in a perpendicular manner.

  The current collecting line 5a has a substantially rectangular cross section, has a thickness of about 10 μm to 20 μm, a width of about 0.1 mm to 2 mm, and an interval (wiring pitch) between adjacent ones of 3 mm to 10 mm. It is about.

  The wiring protective film 6 is made of non-alkali glass containing no alkali metal and has a thickness of about 5 μm to 30 μm. The wiring protective film 6 covers the entire surface (the upper surface 5b and the side surface 5c) of each current collecting line 5a constituting the current collecting wiring 5 so that the surface of the current collecting wiring 5 is not exposed. Is formed. Thus, the wiring protective film 6 protects the current collecting wiring 5 and the electrolyte layer 4 by eliminating physical contact.

  The shield film 7 is formed so as to cover the entire surface of the transparent conductive film 2b, and is formed not only on the part where the wiring protective film 6 exists but also on the part where the wiring protective film 6 does not exist, and is connected to one sheet. It is in the form of a film. The shield film 7 is formed so as to cover the entire surface of the wiring protective film 6 so that the surface of the wiring protective film 6 is not exposed, and is in close contact with the entire surface of the wiring protective film 6. The shield film 7 covers the entire surface of the wiring protective film 6 to physically shield (seal) the current collecting wiring 5 and the wiring protective film 6. The current collector wiring 5 and the wiring protective film 6 are chemically and electrically shielded by the action of the dye 12 described later so as not to cause a chemical reaction with the electrolyte layer 4.

  As shown in detail in FIG. 2, the shield film 7 includes the oxide semiconductor layer 11 and the dye 12, and is thinner than the current collecting wiring 5 and the wiring protective film 6, and has a thickness of about 1 μm to 5 μm. (In FIG. 1, the thick line portion of the shield film 7 indicates the dye 12).

  The oxide semiconductor layer 11 is made of an oxide semiconductor such as amorphous titanium oxide, and has a dense structure in which there is almost no void inside the layer and the inside is almost occupied by the oxide semiconductor to which the dye 12 is adsorbed. is doing. The dye 12 can be a ruthenium complex (N3 or the like) and is densely adsorbed on the entire surface of the oxide semiconductor layer 11 on the electrolyte layer 4 (counter electrode substrate 3) side.

  Since the oxide semiconductor layer 11 has a dense structure made of an oxide semiconductor, it is difficult for the dye 12 to enter the inside. Therefore, although the dye 12 is uniformly and densely adsorbed to the surface layer portion 11c of the oxide semiconductor layer 11 on the electrolyte layer 4 (counter electrode substrate 3) side, within the oxide semiconductor layer 11, the oxide semiconductor layer 11 It is adsorbed only partially. The surface layer portion 11 c means a thin layer portion along the surface 7 a in the vicinity of the surface 7 a in the oxide semiconductor layer 11.

  When the ratio (adsorption rate) in which the dye 12 is adsorbed per unit volume of the oxide semiconductor with respect to such a shield film 7 is observed, in the surface layer portion 11c on the electrolyte layer 4 (counter electrode substrate 3) side, the oxide is present. It becomes higher than the surface layer portion 8c on the electrolyte layer 4 (counter electrode substrate 3) side of the semiconductor porous film 8 (a thin layered portion along the surface 8a in the vicinity of the surface 8a in the oxide semiconductor porous film 8; see FIG. 3). ing. In this way, the shield film 7 has the dye 12 in the surface layer portion 11 c on the electrolyte layer 4 (counter electrode substrate 3) side from the surface layer portion 8 c on the electrolyte layer 4 (counter electrode substrate 3) side of the oxide semiconductor porous film 8. It has a dye adsorbing structure that is adsorbed in a large amount. This is because, since the oxide semiconductor layer 11 has a dense structure made of an oxide semiconductor, a region where the dye 12 can be adsorbed is ensured uniformly over the entire surface layer portion 11c. As will be described later, since the film 8 has a large number of voids 14 in the inside thereof, the region where the dye 15 can be adsorbed is a partial portion of the surface layer portion 8c.

Next, as shown in FIG. 3, the oxide semiconductor porous film 8 includes fine particles 13 of an oxide semiconductor such as titanium oxide (TiO ₂ ) and tin oxide (SnO ₂ ) on which the dye 15 is adsorbed, and the shield film 7. It is formed in a portion between the adjacent current collecting lines 5a and is intermittently arranged. The thickness of the oxide semiconductor porous film 8 is about 5 μm to 50 μm.

  In addition, since the oxide semiconductor porous film 8 does not have a dense structure like the shield film 7, a large number of voids 14 exist therein. Furthermore, although the dye 15 is adsorbed on the surface of each fine particle 13 constituting the oxide semiconductor porous film 8, the adsorption rate of the dye 15 is substantially uniform regardless of whether it is inside or near the surface. ing.

  The dye-sensitized solar cell 1 having the above configuration irradiates light L such as sunlight from the outside of the transparent electrode substrate 2 as shown in FIG. Then, as shown in FIG. 4 (hatching is omitted for the sake of illustration), the dye 15 contained in the oxide semiconductor porous film 8 is excited by absorbing the light L and emits electrons 15a. To do. The electrons 15a move to the transparent electrode substrate 2 side, proceed into the transparent conductive film 2b, are taken out to the outside through the current collecting wiring 5, and move to the counter electrode substrate 3 through wiring not shown.

On the other hand, the dye 15 that has emitted the electrons 15 a becomes holes (h ⁺ ) 15 b, but is regenerated by an oxidation reaction that takes electrons from iodine ions (I ⁻ ) present in the electrolyte layer 4. At this time, iodine ions (I ⁻ ) become iodide ions (I ₃ ⁻ ) by depriving the electrons, but are regenerated by a reduction reaction that receives electrons 16 from the counter electrode substrate 3.

  Thus, in the dye-sensitized solar cell 1, the redox reaction is repeatedly performed by irradiating light L such as sunlight from the outside of the transparent electrode substrate 2, thereby generating electric power.

In the dye-sensitized solar cell 1, the shield film 7 having the dye adsorption structure is formed, and the dye 12 is densely adsorbed on the surface 7a. Since the dye 12 is also excited by absorbing the light L and emits electrons 12a, the surface 7a of the shield film 7 has a large number of electrons 12a and is negatively charged. Therefore, the surface 7a of the shield film 7 and the iodine ion (I ⁻ ) have both negative polarities, so that a Coulomb force repels each other between them, and the shield film 7 is connected to the current collector wiring 5. And it acts to keep iodine ions (I ⁻ ) away from the wiring protective film 6.

Here, as shown in FIG. 5, a case is considered in which the wiring protective film 6 is not covered with the shield film 7 (hatching is omitted for convenience of illustration). The above-described oxidation-reduction reaction is repeated by leaving the energized state in which power is generated. Therefore, the chemical reaction between the components of the wiring protective film 6 and iodine ions (I ⁻ ) is accelerated, and pinholes and cracks are generated in the wiring protective film 6 after a certain period of time has passed.

Then, if the current collector wiring 5 is made of, for example, silver (Ag), silver (Ag) constituting the current collector wiring 5 becomes silver ions (Ag ⁺ ) and dissolves in the electrolyte layer 4, Silver iodide (AgI) is produced from the ions (Ag ⁺ ) and iodine ions (I ⁻ ). In addition, when energized, iodine ions (I ⁻ ) are repeatedly generated by the above-described oxidation-reduction reaction, so that silver iodide (AgI) is also repeatedly generated. Will make it progress.

However, when the wiring protective film 6 is covered with the shield film 7, the dye 12 is densely adsorbed on the surface 7 a of the shield film 7. Therefore, a large number of holes (h ⁺ ) 12b are generated, and each of the holes (h ⁺ ) 12b takes electrons from iodine ions (I ⁻ ), so that a large number of iodide ions (I ₃ ⁻ ) are generated. Become. When iodide ion (I ₃ ⁻ ) reacts with silver iodide (AgI), silver (Ag) and iodine (I) are generated, so that corrosion of the current collector wiring 5 can be suppressed.

Thus, the shielding film 7 positively causes a chemical reaction common to the above-described oxidation-reduction reaction by the dye 12 adsorbed densely generating a large number of holes (h ⁺ ) 12b. The iodine ions (I ⁻ ) that cause corrosion of the current collector wiring 5 are changed to iodide ions (I ₃ ⁻ ). In this way, the shield film 7 chemically shields the current collecting wiring 5 and the wiring protective film 6 so as not to cause a chemical reaction.

The shield film 7 not only changes iodine ions (I ⁻ ) to iodide ions (I ₃ ⁻ ), but also negatively charges the iodine ions (I ⁻ ) to the current collector wiring 5 and the wiring protective film. In this way, the current collecting wiring 5 and the wiring protective film 6 are electrically shielded.

  As described above, since the dye-sensitized solar cell 1 according to the present embodiment chemically and electrically shields the current collecting wiring 5 and the wiring protective film 6 with the shield film 7, it is in a non-energized state. It is possible to prevent the current collecting wiring 5 from being corroded even in an energized state. Therefore, the dye-sensitized solar cell 1 has high durability and can generate power stably over a long period of time.

  Further, in the dye-sensitized solar cell 1, the wiring protective film 6 is made of non-alkali glass, so that a chemical reaction with the electrolyte layer 4 hardly occurs, and therefore the current collector wiring 5 is hardly corroded. ing.

  Further, in the dye-sensitized solar cell 1, the shield film 7 is formed to be thinner than the current collecting wiring 5 and the wiring protective film 6. When the thickness of the shield film 7 is larger than that of the wiring protective film 6, for example, as shown in FIG. 7, a gap 21 is likely to be formed in the connection portion 20 of the wiring protective film 6 with the transparent conductive film 2b. A portion where the shield film 7 does not contact directly appears on the surface of the protective film 6. Even with such a shield film 7, the current collector wiring 5 and the wiring protective film 6 can be shielded chemically and electrically, so that corrosion of the current collector wiring 5 in the energized state can be prevented, but the air gap 21 exists. As a result, the adhesion between the wiring protective film 6 and the shield film 7 decreases. Therefore, the shield film 7 is preferably formed to be thinner than the current collecting wiring 5 and the wiring protective film 6.

  The shield film 7 can be manufactured more easily than intermittently forming like the shield film 37 described later.

(Description of comparative example)
Next, the comparative example performed about the dye-sensitized solar cell 1 which has the above structure is demonstrated. FIG. 8 is a diagram showing a schematic configuration of the light irradiation device 50 used in the comparative example.

  The light irradiation device 50 includes a lamp box 51, a sample stage 52 and a fluorescent lamp 53 arranged in the lamp box 51. The distance between the sample stage 52 and the fluorescent lamp 53 is set to h.

  In this light irradiation device 50, the dye-sensitized solar cell 1 is placed on the lamp box 51, and the light L is irradiated from the upper side thereof with the fluorescent lamp 53 so that the dye-sensitized solar cell 1 generates power. It has become.

  The following comparative example differs from the dye-sensitized solar cell 1 (solar cell with a shield film) described above in that it does not have the shield film 7, and the other dyes have the same configuration as the dye-sensitized solar cell 1. With respect to the sensitized solar cell (shield film-less solar cell), power generation using this light irradiation device 50 is performed, and the degree of corrosion of the current collecting wiring 5 in both is compared.

  The light irradiation device 50 was set at a temperature of 30 ° C. and a humidity of 45% inside, and continued to irradiate the light L with the fluorescent lamp 53 for 24 hours in such an environment. In this case, the number of corroded portions was measured before irradiation with the light L and when several days had elapsed from the start of irradiation, and the area of the corroded portion was roughly calculated when the 31st day from the start of irradiation.

  Then, in the solar cell with a shield film, the number of corrosion spots was 0 before irradiation. On the 30th day, there were 3 corrosion spots, but even on the 31st day, the number of corrosion spots did not change.

On the other hand, in the solar cell without a shield film, although the number of corroded portions was 0 before irradiation, 9 appeared on the third day from the start of irradiation. On the fifth day, the number of corrosion spots was 19, and on the 31st day, the number of corrosion spots was increased to 32. In addition, the area of the corroded portion was 0.0035 cm ² in the solar cell with the shield film, but increased to 0.0968 cm ² in the solar cell without the shield film.

  FIGS. 9 and 10 are photographs taken from above of the solar cell with a shield film. FIG. 9 shows an initial state and FIG. 10 shows the 31st day. 11 and 12 are photographs taken from above of a solar cell without a shield film. FIG. 11 shows an initial state, and FIG. 12 shows the 31st day. In each figure, corrosion of the current collector wiring 5 appears at a circle.

As described above, in the solar cell without a shield film, the number of corrosion sites increases to 32 on the 31st day, and the area of the corrosion portion expands to 0.0968 cm ² , whereas in the solar cell with a shield film Even on the 31st day, the number of corroded portions is limited to three, and the area of the corroded portion is also suppressed to 0.0035 cm ² . Also from this comparative example, it is clear that by using a solar cell with a shield film, corrosion of the current collecting wiring 5 in an energized state can be prevented and durability can be enhanced.

(Modification 1)
FIG. 13 is a cross-sectional view showing a configuration of a dye-sensitized solar cell 31 according to a modification. The dye-sensitized solar cell 31 is different from the above-described dye-sensitized solar cell 1 in that it has an electrode substrate with wiring 39, and the others have a common configuration. The electrode substrate with wiring 39 is different from the electrode substrate with wiring 9 in that it has a shield film 37, and the others have a common configuration.

  The shield film 37 is common to the shield film 7 in that the material has the same composition, but is formed only in a portion where the wiring protective film 6 exists and is formed in a portion where the wiring protective film 6 does not exist. It is not, and therefore differs in that it is formed intermittently.

  Since the shield film 37 also covers the entire surface of the wiring protective film 6 so that the surface of the wiring protective film 6 is not exposed like the shield film 7, the current collecting wiring 5 and the wiring protective film 6 are chemically treated. Shielded electrically and electrically. Therefore, the dye-sensitized solar cell 31 can also prevent the corrosion of the current collecting wiring 5 in the energized state and enhance the durability, like the dye-sensitized solar cell 1.

(Modification 2)
FIG. 14 is a cross-sectional view showing a configuration of a dye-sensitized solar cell 41 according to another modification. The dye-sensitized solar cell 41 is different from the above-described dye-sensitized solar cell 1 in that it has an electrode substrate 49 with wiring, and the others have a common configuration. The electrode substrate with wiring 49 is different from the electrode substrate with wiring 9 in that it has a shield film 47 and an oxide semiconductor porous film 48, and others have a common configuration.

The shield film 47 is made of an oxide semiconductor such as titanium oxide (TiO ₂ ) and tin oxide (SnO ₂ ), and is configured by accumulating and accumulating many fine particles having a fine structure. Each fine particle has a large average particle diameter of 40 nm or less, preferably 15 nm or less, so that the fine particles are closely gathered and accumulated. Thus, the fine particles different from the oxide semiconductor porous film 8 are accumulated. It has a structure. Moreover, although each pigment | dye has adsorb | sucked the pigment | dye to the surface, it has gathered closely. Therefore, like the shield film 7, the shield film 47 is larger in the surface layer part on the electrolyte layer 4 (counter electrode substrate 3) side than the surface layer part on the electrolyte layer 4 (counter electrode substrate 3) side of the oxide semiconductor porous film 48. It has a dye adsorption structure in which a dye is adsorbed.

  The oxide semiconductor porous film 48 is different from the oxide semiconductor porous film 8 in that it is formed so as to cover the entire transparent conductive film 2b.

  Since the dye-sensitized solar cell 41 having such a shield film 47 also covers the entire surface of the wiring protective film 6 so that the surface of the wiring protective film 6 is not exposed, the current collecting wiring 5 and the wiring protective film 6 is chemically and electrically shielded. Therefore, the dye-sensitized solar cell 41 can also prevent the corrosion of the current collecting wiring 5 in the energized state and enhance the durability, like the dye-sensitized solar cell 1. Moreover, since the oxide semiconductor porous film 48 is formed so as to cover the entire transparent conductive film 2 b, it can be manufactured more easily than the dye-sensitized solar cell 1.

  In the above embodiment, the dye-sensitized solar cells 1, 31, 41 having the shield films 7, 37, 47 having the dye adsorption structure are described as an example. However, the current collector wiring 5 and the wiring protective film are described. If it is a structure which shields 6 chemically and electrically, you may have a shield film provided with other structures.

  The above description is the description of the embodiment of the present invention, and does not limit the apparatus and method of the present invention, and various modifications can be easily implemented. In addition, an apparatus or method configured by appropriately combining components, functions, features, or method steps in each embodiment is also included in the present invention.

  By applying the present invention, the dye-sensitized solar cell and the electrode substrate with wiring used therein can be prevented from corroding the current collecting wiring to enhance the durability. By such a dye-sensitized solar cell, It will be possible to generate power stably over a long period of time.

  DESCRIPTION OF SYMBOLS 1,31,41 ... Dye-sensitized solar cell, 2 ... Transparent electrode substrate, 3 ... Counter electrode substrate, 4 ... Electrolyte layer, 5 ... Current collection wiring, 6 ... Wiring protective film, 7, 37, 47 ... Shield film 8, 48 ... oxide semiconductor porous film, 9, 39, 49 ... electrode substrate with wiring, 11 ... oxide semiconductor layer, 12, 15 ... dye, 13 ... fine particles, 2a ... transparent substrate, 2b ... transparent conductive film.

Claims (11)

A transparent electrode substrate having a transparent conductive film formed on one side of the transparent substrate, and a counter electrode substrate facing the transparent electrode substrate, and an electrolyte layer between the transparent electrode substrate and the counter electrode substrate A dye-sensitized solar cell in which is formed,
Current collector wiring formed on the transparent conductive film;
A wiring protective film formed on the surface of the current collector wiring;
A dye-sensitized solar cell, characterized in that it has a surface of the wiring protective film and a shield film that chemically and electrically shields the current collecting wiring and the wiring protective film.   2. The dye-sensitized solar cell according to claim 1, further comprising an oxide semiconductor porous film comprising oxide semiconductor fine particles adsorbed with the dye.   The shield film is composed of an oxide semiconductor to which a dye is adsorbed, and the dye is densely formed on a surface layer portion of the oxide semiconductor on the counter electrode substrate side and on the counter electrode substrate side of the oxide semiconductor porous film. 3. The dye-sensitized solar cell according to claim 2, wherein the dye-sensitized solar cell has a dye adsorbing structure adsorbed more than the surface layer portion.   The dye-sensitized solar cell according to any one of claims 1 to 3, wherein the shield film is formed so as to cover the entire transparent conductive film.   5. The dye-sensitized solar cell according to claim 3, wherein the oxide semiconductor constituting the shield film has an amorphous structure having substantially no voids therein.   5. The dye-sensitized type according to claim 3, wherein the shield film has a dense structure composed of oxide semiconductor fine particles to which a dye is adsorbed and having an average particle diameter smaller than that of the oxide semiconductor porous film. Solar cell.   The dye-sensitized solar cell according to any one of claims 1 to 6, wherein the shield film is formed to be thinner than the current collecting wiring and the wiring protective film.   The dye-sensitized solar cell according to any one of claims 1 to 7, wherein the wiring protective film is formed using non-alkali glass containing no alkali metal. A transparent electrode substrate having a transparent conductive film formed on one side of the transparent substrate, and a counter electrode substrate facing the transparent electrode substrate, and an electrolyte layer between the transparent electrode substrate and the counter electrode substrate An electrode substrate with wiring used for a dye-sensitized solar cell in which is formed,
The transparent electrode substrate;
Current collector wiring formed on the transparent conductive film;
A wiring protective film formed on the surface of the current collector wiring;
An electrode substrate with wiring, characterized by having a shield film that covers the surface of the wiring protective film and shields the current collector wiring and the wiring protective film chemically and electrically.   The electrode substrate with wiring according to claim 9, further comprising an oxide semiconductor porous film made of oxide semiconductor fine particles adsorbed with a dye.   The shield film is composed of an oxide semiconductor to which a dye is adsorbed, and the dye is densely formed on a surface layer portion of the oxide semiconductor on the counter electrode substrate side and on the counter electrode substrate side of the oxide semiconductor porous film. The electrode substrate with wiring according to claim 10, wherein the electrode substrate has a dye adsorbing structure adsorbed more than the surface layer portion.