JP4932200B2 - Electrode, manufacturing method thereof, and photoelectric conversion element - Google Patents

Description

  The present invention relates to an electrode using a porous carbon member as a counter electrode used in a photoelectric conversion element such as a dye-sensitized solar cell, a method for producing the same, and a photoelectric conversion element including the electrode.

  Dye-sensitized solar cells were developed by Gretzell et al. In Switzerland, and have the advantages of high photoelectric conversion efficiency and low manufacturing costs, and are attracting attention as new types of solar cells (for example, patents) Documents 1 and 2 and Non-Patent Document 1).

  As shown in FIG. 3, the general structure of this dye-sensitized solar cell is usually an oxide such as titanium dioxide on a transparent conductive electrode substrate composed of a first base material 102 and a transparent conductive film 104. The working electrode 108 is formed by forming a porous film 105 made of semiconductor fine particles. On the other hand, the second substrate 103 coated with a conductive layer 107 such as platinum is provided as a counter electrode 109, and the porous film 105 of the working electrode 108 is provided on the porous film 105. A photosensitizing dye is supported, and an electrolyte 106 containing a redox pair is filled between the working electrode 108 and the counter electrode 109. In this type of dye-sensitized solar cell 101, oxide semiconductor fine particles are sensitized by a photosensitizing dye that absorbs incident light such as sunlight (indicated as hν in FIG. 3), and the working electrode 108, the counter electrode 109, When an electromotive force is generated during this period, it functions as a photoelectric conversion element that converts light energy into electric power.

As a counter electrode of the dye-sensitized solar cell, an electrode having a platinum film formed by vapor deposition or sputtering on a conductive electrode substrate or a metal plate is generally used.
However, platinum is expensive, and sputter film formation is a vacuum process, so that there is a limit to manufacturing at low cost. Depending on the electrolyte, platinum may be dissolved, resulting in deterioration of power generation characteristics.

On the other hand, a dye-sensitized solar cell aiming at long-term stability has been developed by using a counter electrode using carbon that is cheaper than platinum and chemically stable (see, for example, Patent Document 3). .
However, in the case of a counter electrode using carbon, since the carbon used as the counter electrode is a sintered body, the surface is not smooth and there are fine voids, and the electrolytic solution gradually infiltrates into the voids. After assembly, there is a risk that it will stop working after a while.
Japanese Patent No. 2664194 JP 2001-160427 A JP 2004-152747 A M. Graetzel et al., Nature (UK), 1991, No. 737, p. 353

  The present invention has been made in view of the above circumstances, and suppresses permeation of the electrolytic solution into the electrode made of a porous carbon member, and an electrode suitable for a photoelectric conversion element excellent in long-term stability of power generation characteristics and a method for manufacturing the same, An object of the present invention is to provide a photoelectric conversion element using this electrode.

The electrode according to claim 1 of the present invention is an electrode that forms a counter electrode that is disposed at least partially via an electrolyte layer with respect to the working electrode, and the counter electrode is at least porous on the side in contact with the electrolyte layer It is composed of a carbon member, and a conductive oxide is locally arranged only on the electrolyte layer side of the porous carbon member.
An electrode according to a second aspect of the present invention is the electrode according to the first aspect, wherein the conductive oxide is filled in at least a part or the whole of the void portion facing the electrolyte layer of the porous carbon member. And
A method for producing an electrode according to claim 3 of the present invention is a method for producing an electrode that constitutes a counter electrode that is disposed at least partially through an electrolyte layer with respect to a working electrode, and carbon is applied to one surface of a substrate. A step α for forming a carbon member by applying a paste as a main component, a step β for forming a porous carbon member by subjecting the carbon member to a heat treatment, and a locally conductive oxidation on the porous carbon member And at least a step γ for forming an object.
According to a fourth aspect of the present invention, there is provided the electrode manufacturing method according to the third aspect, wherein in the step γ, the conductive oxide raw material solution is sprayed toward the porous carbon member, and the conductive oxide is porous. The conductive carbon member is provided so as to cover all the electrolyte layer side, and then the conductive oxide is processed, thereby filling the conductive oxide with a part or all of the voids of the porous carbon member. It is characterized by that.
The electrode manufacturing method according to claim 5 of the present invention is the electrode manufacturing method according to claim 3, wherein the step γ sprays a raw material solution of a conductive oxide toward the porous carbon member, and the conductive oxide is porous. The conductive oxide is filled in part or all of the voids of the porous carbon member by partially covering the electrolyte layer side of the porous carbon member.
The photoelectric conversion element according to claim 6 of the present invention is a photoelectric conversion element provided with an electrode forming a counter electrode that is disposed at least partially via an electrolyte layer with respect to the working electrode, wherein the electrode is The side in contact with the electrolyte layer is composed of at least a porous carbon member, and a conductive oxide is locally disposed only on the electrolyte layer side of the porous carbon member.

  In the electrode according to the present invention, the side in contact with the electrolyte layer is composed of at least a porous carbon member, and a conductive oxide is locally disposed on the electrolyte layer side of the porous carbon member. It is possible to suppress the penetration of the electrolytic solution, which is an electrolyte, into the porous carbon member, and to provide an electrode that does not cause deterioration of power generation characteristics over a long period of time. In addition, the electrode reaction is relatively stable due to the low electrical resistance of the conductive oxide, and the electrode can be suitable for a photoelectric conversion element with excellent power generation efficiency.

  Further, in the method for producing an electrode according to the present invention, since at least the step γ for locally forming a conductive oxide on the porous carbon member is provided, the penetration of the electrolyte as an electrolyte into the porous carbon member is suppressed. At the same time, it is possible to easily manufacture an electrode in which a conductive oxide capable of smoothly proceeding an electrode reaction with a low electric resistance is locally disposed on the electrolyte layer side of the porous carbon member.

  Furthermore, in the photoelectric conversion element using the electrode according to the present invention, the side in contact with the electrolyte layer is composed of at least a porous carbon member, and a conductive oxide is locally disposed on the electrolyte layer side of the porous carbon member. Are provided as counter electrodes. The electrode having this configuration suppresses permeation of the electrolyte, which is an electrolyte, into the porous carbon member and reduces the change in electrical characteristics over time, so that a photoelectric conversion element with stable power generation characteristics can be obtained over the long term. It will be a thing.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing the structure of a photoelectric conversion element using the electrode of the present invention, and FIG. 2 is a partially enlarged schematic sectional view for explaining the structure of the electrode of the photoelectric conversion element shown in FIG.
As shown in FIG. 1, the photoelectric conversion element 1 according to the present invention has a three-layered transparent substrate composed of a first base material 2, a transparent conductive film 4, and a porous oxide semiconductor layer 5. A window electrode (working electrode) substrate 8 is used. On the other hand, an electrode substrate composed of the second base material 3, the porous carbon member 7 and the conductive oxide 14 is used as a counter electrode substrate 9. The electrolyte solution (or electrolyte gel) 6 is sandwiched.

The first base material 2 is not particularly limited as long as it is a transparent member having electrical conductivity that conducts electricity by forming a film (layer) made of a conductive material on the surface and having high light transmittance. As the first base material 2, a glass plate is generally used, but other than the glass plate, for example, plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polycarbonate (PC). A ceramic polishing plate such as a sheet, titanium oxide, or alumina can be used. Here, the surface refers to the surface of the substrate surface that is disposed opposite to the porous carbon member 7 that forms the transparent conductive film 4 and the like and acts as a counter electrode.
In addition, the first base material 2 is a conductive material that can withstand high heat of about 500 ° C. when titanium dioxide (TiO ₂ ) is baked on the substrate on which a transparent conductive film is formed later as the porous oxide semiconductor 5 for supporting the dye. It is desirable to use heat resistant glass.

The transparent conductive layer 4 is a conductive film having a high light transmittance made of a conductive material formed on the first substrate 2. As the transparent conductive layer 4, for example, a transparent oxide semiconductor such as tin-added indium oxide (ITO), tin oxide (SnO ₂ ), or fluorine-added tin (FTO) is used alone or in combination of a plurality of types. However, it is not particularly limited, and a material that meets the purpose of use in terms of light transmittance and conductivity may be selected. Further, in order to provide a conductive assist (collecting current) effect, a metal wiring or the like may be added within a range that does not significantly impair the light transmittance.
And it is set as the window electrode board | substrate by forming the transparent conductive layer 4 on the 1st base material 2. FIG.

There are no particular limitations on the material and formation method of the porous oxide semiconductor layer 5, for example, titanium dioxide (TiO ₂ ), tin oxide (SnO ₂ ), tungsten oxide (WO ₃ ), zinc oxide (ZnO). ), Niobium oxide (Nb ₂ O ₅ ) or the like, or a composite of two or more, and is a porous thin film mainly composed of oxide semiconductor particles having an average particle diameter of 15 nm to 30 nm, and commercially available fine particles Or a colloidal solution obtained by a sol-gel method.

  As a method for forming a porous film, for example, colloidal solutions and dispersions (including additives as necessary), various coating methods such as screen printing, inkjet printing, roll coating, doctor blade, spin coating, spray coating, etc. In addition to coating by coating, electrophoretic electrodeposition of fine particles, combined use of a foaming agent, etc. may be used. The porous oxide semiconductor layer 5 carries a sensitizing dye.

  As the sensitizing dye, for example, a ruthenium complex containing a bipyridine structure, a terpyridine structure or the like as a ligand, a metal-containing complex such as porphyrin, phthalocyanine, or an organic dye such as erosine, rhodamine, or merocyanine can be used. An appropriate material can be selected without particular limitation depending on the use and the porous semiconductor membrane to be used.

  Further, the second base material 3 is a substrate on which the porous carbon member 7 used for the counter electrode is provided. Like the first base material 2, a glass plate is generally used. In addition to the glass plate, for example, it is possible to use a titanium (Ti) plate or a carbon plate that has good electrical conductivity and can be freely designed in thickness.

  As shown in FIG. 2, the porous carbon member 7 has a carbon portion 7 </ b> A and a fine gap portion 7 </ b> B at least on the side facing the electrolytic solution 6. Therefore, the fine void portion 7B may be provided in the entire porous carbon member 7.

  The porous carbon member 7 is formed by, for example, forming a carbon film by applying or printing a carbon paste containing a solvent on the second substrate 3, and evaporating the solvent contained by heating the carbon film. It can be formed to have a fine gap 7B. As shown in FIG. 1, the porous carbon member 7 described above is a film body provided on the second base material 3, but may be a plate body that also serves as the second base material 3.

  Further, a conductive oxide 14 is locally disposed on the electrolyte solution 6 side of the porous carbon member 7. Therefore, the porous carbon member 7 has a region where the carbon portion is exposed and a region covered with the conductive oxide 14 on the side in contact with the electrolytic solution 6.

The conductive oxide 14 is a conductive material having electrical conductivity. Examples thereof include tin-added indium oxide (ITO), tin oxide (SnO ₂ ), and fluorine-added tin (FTO). Is locally disposed on the electrolyte solution 6 side. Thereby, the penetration of the electrolytic solution 6 into the porous carbon member 7 can be suppressed, and the electrode reaction can be relatively stably ensured by the low electric resistance.

  Specifically, as shown in FIG. 2, the conductive oxide 14 is preferably filled in at least a part or the whole of the void 7 </ b> B facing the electrolyte layer 6 of the porous carbon member 7. Thereby, the electroconductive oxide 14 block | closes the fine space | gap part 7B on the surface of the porous carbon member 7 locally, and suppresses further so that the electrolyte solution 6 may not penetrate | infiltrate into the space | gap part 7B. . Therefore, it can be set as the electrode which does not cause deterioration of power generation characteristics over a long period of time.

  The conductive oxide 14 can be formed by, for example, a spray pyrolysis method (SPD), a sputtering method, a CVD method, or the like, but in a dry process such as a sputtering method, fine voids formed in the porous carbon member 7 are used. Since it is difficult to produce in 7B, when filling the void 7B of the porous carbon member 7, it is necessary to produce it by thermal decomposition from the liquid phase. The conductive oxide 14 is not particularly required to be transparent.

  Moreover, the electrolyte solution 6 refers to a conductive solution in which the electrolyte is dissociated in the solution to generate cations and anions. As the electrolytic solution 6, for example, an organic solvent containing a redox pair, an ionic liquid (room temperature molten salt), or the like can be used. The oxidation-reduction pair is not particularly limited. For example, iodine / iodide ion, bromine / bromide ion, etc. can be selected. In the former case, iodide salt (lithium salt, quaternized imidazolium salt, tetra Butylammonium salt and the like can be used alone or in combination, and iodine can be added alone or in combination.

Examples of the organic solvent include volatile electrolytes using acetonitrile, methoxyacetonitrile, propionitrile, ethylene carbonate, propylene carbonate, diethyl carbonate, γ-butyrolactone, and the like.
Examples of the ionic liquid include, for example, a room temperature molten salt which is a liquid at room temperature using a compound having a quaternized nitrogen atom such as a quaternized imidazolium derivative, a quaternized pyridinium derivative, or a quaternized ammonium derivative as a cation. Is mentioned.

Further, a so-called gel electrolyte may be used in which the electrolytic solution 6 is pseudo-solidified by introducing an appropriate gelling agent and filler to suppress fluidity.
Various additives such as lithium salt and tert-butylpyridine may be further added to the electrolytic solution 6 as necessary. Further, a polymer solid electrolyte having a charge transporting ability as in the case of such an electrolytic solution may be used.

  As described above, according to the present embodiment, the porous carbon member having fine voids on the surface is used as the counter electrode that is electrically arranged at least partially via the electrolyte layer with respect to the working electrode. Even in such a case, the conductive oxide is locally disposed to prevent the electrolyte from penetrating into the gap, and the electrode does not cause deterioration of power generation characteristics over a long period of time. In addition, the electrode reaction can be ensured relatively stably, and the photoelectric conversion element having excellent power generation efficiency and long-term stability can be obtained.

Next, an example of a method for producing a photoelectric conversion element according to the present invention will be described.
First, a window electrode substrate is formed by forming a transparent conductive film on a first substrate such as a glass plate. As a method for forming the transparent conductive film, a known method may be used depending on the material of the transparent conductive film. For example, a sputtering method, a CVD method (vapor phase growth method), an SPD method (spray pyrolysis deposition method). A thin film made of an oxide semiconductor such as tin-added indium oxide (ITO) is formed by a vapor deposition method or the like. Thereby, an electroconductive board | substrate is comprised. And, if this transparent conductive film is too thick, the light transmittance is inferior, whereas if it is too thin, the conductivity is inferior, so that both the light transmittance and the conductivity are taken into consideration. A film thickness of about 1.0 μm is preferable.

Next, a window electrode as a working electrode is formed by forming a porous oxide semiconductor layer on the transparent conductive film. As a method for forming a porous oxide semiconductor layer, for example, a titanium dioxide (TiO ₂ ) powder is mixed with a dispersion medium to prepare a paste, and this is used for a screen printing method, an ink jet printing method, a roll coating method, a doctor blade. It coats on a conductive substrate by a method, a spin coat method, etc. As this porous oxide semiconductor layer, a thin film of about 10 μm to 20 μm is preferable. Thus, a conductive substrate (electrode substrate) is formed, and sunlight (denoted as hν in FIG. 1) enters the photoelectric conversion element through the electrode substrate.
And a pigment | dye is carry | supported by a porous oxide semiconductor layer by immersing the window pole in which the porous oxide semiconductor layer was formed in a pigment | dye liquid.

On the other hand, on a second substrate such as a titanium (Ti) plate, a carbon paste containing a solvent is applied or printed to form a carbon film, which is then heat treated to evaporate the contained solvent, thereby making the porous The counter electrode which forms a carbon member is comprised.
As a method for forming the porous carbon member, first, a carbon paste containing polyethylene glycol as a solvent is applied onto the second substrate by a screen printing method or the like to form a carbon film. This carbon film is formed to a thickness of about 1 μm to 5 μm. Next, this carbon film is baked at 450 ° C. for 10 minutes, for example. As a result, polyethylene glycol is decomposed as a solvent from the carbon film, and voids are generated at the decomposed portions, thereby forming a porous carbon member.

Next, a conductive oxide is locally disposed on the porous carbon member. The conductive oxide can be formed, for example, by spray pyrolysis (SPD).
When this conductive oxide is locally disposed, first, the porous carbon member is heated to a predetermined temperature. Next, using a spraying means such as an atomizer, the conductive oxide raw material solution is sprayed toward the heated porous carbon member, and the conductive oxide covers the entire surface of the porous carbon member. Provide as follows. As a result, the evaporation of the solvent in the droplets attached to the surface of the porous carbon member reacts with the solute to form crystals, and the reaction gradually proceeds to cover the porous carbon member with the conductive oxide. . The conductive oxide raw material solution is soaked and filled in part or all of the voids on the surface of the porous carbon member, so that the conductive oxide film extends over a certain depth from the surface of the porous carbon member. Can be formed.

  Thereafter, the conductive oxide provided so as to cover the entire surface of the porous carbon member is subjected to, for example, polishing, and the surface of the porous carbon member is removed by removing the outermost surface of the conductive oxide very thinly. The conductive oxide is left locally to expose the carbon portion. As a result, the carbon part of the exposed porous carbon member has a function as a counter electrode, and the conductive oxide is easily and surely filled into part or all of the voids on the surface of the porous carbon member. Can be.

  The method comprises a step of providing a conductive oxide so as to cover the entire surface of the porous carbon member, and a step of processing the conductive oxide provided so as to cover the entire surface of the porous carbon member. Although the conductive oxide is locally disposed by two steps, in the present invention, the conductive oxide may be directly disposed by one step described below.

  When the conductive oxide is locally arranged in one step, first, the porous carbon member is heated to a predetermined temperature. Next, using a spraying means such as an atomizer, a conductive oxide raw material solution is sprayed toward the heated porous carbon member, and the conductive oxide locally spreads the surface of the porous carbon member. In other words, it is provided so as to selectively cover the voids on the surface of the porous carbon member. That is, the deposition of the dielectric oxide is promoted only in the void portion that forms a depression on the surface of the porous carbon member. Thereby, the conductive oxide can be efficiently filled in part or all of the voids on the surface of the porous carbon member in one step.

  And the porous oxide semiconductor layer of the window electrode and the porous carbon member of the counter electrode are arranged to face each other, and the electrolyte according to the present invention is sealed by filling the electrolyte solution as an electrolyte layer between them. A dye-sensitized solar cell is manufactured as the photoelectric conversion element.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited to a following example.
Example 1
In this example, in order to confirm that the electrode of the present invention is composed of a porous carbon member and that a conductive oxide is desirably locally disposed on the electrolyte layer side of the porous carbon member, Each counter electrode described was prepared and its photoelectric conversion efficiency was measured.

First, a porous carbon plate of 9 mm × 11 mm × 1 mm ^t was prepared as a substrate and heated so that the surface temperature of the porous carbon plate was 400 ° C. Next, under the conditions shown in Table 1 below, a conductive oxide raw material solution is sprayed toward the heated porous carbon plate by a spray pyrolysis (SPD) method to form a fluorine-added tin (FTO) film. Formed. Next, the surface of the fluorine-added tin (FTO) film is subjected to a mechanical polishing process using No. 1200 SiC paper to remove the conductive oxide very thinly, thereby exposing the carbon of the substrate. A window-side electrode in which a conductive oxide was locally arranged was produced.

In addition, as a comparative example 1, a 9 mm × 11 mm × 1 mm ^t porous carbon plate alone was prepared as a counter electrode, and as a comparative example 2, a 9 mm × 11 mm × 1 mm ^t FTO glass electrode substrate was used, and the upper surface thereof was formed by sputtering. A counter electrode was prepared by coating an electrode layer made of platinum with a thickness of 50 nm.

On the other hand, a heat-resistant glass of 9 mm × 11 mm × 1 mm ^t was used as the first base material, and a composite film with a sheet resistance of 2Ω / □ [fluorine-added tin (FTO) film was superimposed on the ITO film] on the upper surface by SPD method. The laminated film] was formed as a transparent conductive layer to a total thickness of 780 nm [ITO (600 nm) / FTO (180 nm)] to obtain an electrode substrate. Next, a titanium oxide electrode layer having a size of 9 mm × 5 mm is formed as a porous oxide semiconductor on the electrode substrate, and an N3 dye [Ru (2, 2′-bipyridine-4, 4′- dicarboxylic acid) ₂ (NCS) ₂ ] was used to form a window-side electrode of a dye-sensitized solar cell.

Then, each counter electrode produced and the window side electrode were overlapped, and a volatile electrolyte solution using methoxyacetonitrile as a solvent was used as an electrolyte. The electrolyte solution was filled between both electrodes, and a dye-sensitized solar cell was assembled and tested. The cell was irradiated with light, and the photoelectric conversion efficiency in the dye-sensitized solar cell was measured. Moreover, the photoelectric conversion efficiency was similarly measured 24 hours after the test cell was produced. At this time, the light irradiation condition was 100 mW / cm ² . The measurement results are shown in Table 2 (average value at n = 3).

  Furthermore, the short circuit current density in the said dye-sensitized solar cell, the open end voltage, the fill factor, and sheet resistance were also measured after cell preparation. The short-circuit current density, open-circuit voltage, and fill factor are all measured with an IV curve tracer (manufactured by EKO Co., Ltd., MP-160), and the sheet resistance is measured with a resistivity meter (manufactured by Mitsubishi Chemical Corporation, MCP-T600). Each was measured. These measurement results are summarized in Table 2.

From Table 2, the following points became clear.
(1) When the counter electrode is composed of a porous carbon member and the conductive oxide is locally disposed on the electrolyte layer side of the porous carbon member (Example 1), the conductive oxide is an electrolyte solution. Infiltration is suppressed, and power generation is maintained even 24 hours after cell fabrication.
(2) When only the porous carbon plate was used as the counter electrode (comparative example 1) (Comparative Example 1), power generation was not possible after 24 hours from the cell production, and the photoelectric conversion efficiency could not be measured. In addition, when the cell of Comparative Example 1 that only generated power 24 hours after cell preparation was disassembled, it was found that the electrolyte soaked into the counter electrode and almost no gap was present between the electrodes.
(3) In the case where an electrode layer made of platinum is provided on the FTO glass plate as a counter electrode (Comparative Example 2), stable power generation characteristics can be obtained in the long term.

  From the above results, some electrolytes may dissolve and cause deterioration of power generation characteristics, and carbon that is extremely cheaper than platinum and chemically stable is used without using platinum known as an expensive material. It has been confirmed that the electrode according to the present invention contributes to the provision of a photoelectric conversion element excellent in long-term stability.

  Moreover, the counter electrode of Example 1 based on this invention has exceeded each counter electrode of the comparative example 1 which made each porous carbon board single-piece | unit, and it will become a desirable thing approaching the counter electrode of the comparative example 2 which uses platinum. It was. In Example 1, the sheet resistance is slightly lower than that in Comparative Example 1, which is considered to be because the conductive oxide was filled in the fine voids.

  As described above, FTO was produced by the SPD method in this example. However, the present invention is not necessarily this method. For example, after a substrate composed of a porous carbon member is immersed in a raw material solution of a conductive oxide Then, heating is repeated to form an FTO film on the porous carbon member, and then the polishing process is performed to remove the FTO on the outermost surface very thinly, thereby exposing the carbon portion of the porous carbon member. FTO may be left locally on the porous carbon member. In addition, the conductive oxide is not limited to FTO, and any conductive oxide generated by thermal decomposition from a liquid phase can be applied.

It is a schematic sectional drawing which shows the structure of the photoelectric conversion element using the electrode which concerns on this invention. It is a partial expanded schematic sectional drawing explaining the structure of the electrode of the photoelectric conversion element shown in FIG. It is a schematic sectional drawing which shows the structure of the photoelectric conversion element using the conventional electrode.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photoelectric conversion element (dye-sensitized solar cell), 2nd base material, 2nd base material, 4 transparent conductive layer, 5 porous oxide semiconductor layer, 6 electrolyte layer, 7 porous carbon member, 7A carbon part , 7B gap, 8 window electrode (working electrode) substrate, 9 counter electrode substrate, 14 conductive oxide.

Claims (6)

An electrode constituting a counter electrode disposed at least partially with respect to the working electrode via an electrolyte layer, wherein the counter electrode is composed of at least a porous carbon member on a side in contact with the electrolyte layer, and the porous carbon member A conductive oxide is locally disposed only on the electrolyte layer side of the electrode.   2. The electrode according to claim 1, wherein the conductive oxide is filled in at least a part or the whole of the void portion facing the electrolyte layer of the porous carbon member.   A method of manufacturing an electrode that forms a counter electrode that is disposed at least partially through an electrolyte layer with respect to a working electrode, wherein a carbon member is formed by applying a carbon-based paste on one surface of a substrate. It comprises at least a step α, a step β in which a heat treatment is performed on the carbon member to form a porous carbon member, and a step γ in which a conductive oxide is locally formed on the porous carbon member. A method for producing an electrode.   In the step γ, a conductive oxide raw material solution is sprayed toward the porous carbon member, and the conductive oxide is provided so as to cover the entire electrolyte layer side of the porous carbon member. The method for producing an electrode according to claim 3, wherein the conductive oxide is filled into a part or all of the voids of the porous carbon member by processing the oxide.   In the step γ, the raw material solution of the conductive oxide is sprayed toward the porous carbon member, and the conductive oxide is provided so as to partially cover the electrolyte layer side of the porous carbon member. The method for producing an electrode according to claim 3, wherein a conductive oxide is filled in part or all of the voids of the porous carbon member. A photoelectric conversion element comprising a counter electrode arranged at least partially with respect to a working electrode via an electrolyte layer, wherein the electrode is formed of at least a porous carbon member on the side in contact with the electrolyte layer A photoelectric conversion element, wherein a conductive oxide is locally disposed only on the electrolyte layer side of the porous carbon member.

Images