JP4298195B2 - Photoelectric cell - Google Patents

Description

【図面の簡単な説明】
【図１】 図１は本発明に係る光電気セルの一実施例を示す概略断面図を示す。
【符号の説明】
１…透明電極層
２…半導体膜
2-A…下層多孔質半導体膜
2-B…上層多孔質半導体膜
３…電極層
４…電解質層
５…透明基板
６…基板[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a novel photovoltaic cell. More specifically, the present invention relates to a photoelectric cell having high photoelectric conversion efficiency, and a photoelectric cell usually referred to as tandem dye sensitization.
[0002]
[Prior art]
The photoelectric conversion material is a material that can continuously extract light energy as electric energy, and is a material that converts light energy into electric energy using an electrochemical reaction between electrodes. When the photoelectric conversion material is irradiated with light, electrons are generated on one electrode side, move to the counter electrode, and the electrons moved to the counter electrode move as ions in the electrolyte and return to the one electrode. Thus, since energy conversion is continuous, it is utilized for a solar cell etc., for example.
[0003]
In general solar cells, a semiconductor film for a photoelectric conversion material is formed on a support such as a glass plate coated with a transparent conductive film to form an electrode, and then another transparent conductive film is coated as a counter electrode. A support such as a glass plate is provided, and an electrolyte is sealed between these electrodes.
When the spectral sensitizing dye adsorbed on the photoelectric conversion material semiconductor is irradiated with sunlight, the spectral sensitizing dye absorbs light in the visible region and is excited. The electrons generated by this excitation move to the semiconductor, then move to the transparent conductive glass electrode, move to the counter electrode through the conducting wire connecting the two electrodes, and the electrons transferred to the counter electrode are oxidized in the electrolyte. Reduce the reduction system. On the other hand, the spectral sensitizing dye having electrons transferred to the semiconductor is in an oxidant state, but this oxidant is reduced by the redox system in the electrolyte and returns to its original state. Thus, since electrons flow continuously, it functions as a solar cell using a semiconductor for photoelectric conversion materials.
[0004]
As the electrolyte used by sealing between the electrodes, a liquid electrolyte (electrolytic solution) in which an electrolyte is dissolved in a solvent is used, or a solid electrolyte (when the viscosity is approximately 10 cp or more, or a gel-like material is also called a solid electrolyte). After the encapsulation, the photoelectric cell is sealed by sealing the side with a resin or the like.
When an electrolytic solution is used as an electrolyte, it may be difficult to obtain sufficient photoelectric conversion efficiency due to difficulty in diffusion of the electrolyte depending on the semiconductor film.
[0005]
This tendency is particularly noticeable when a solid electrolyte is used as the electrolyte. When a polymer electrolyte is used as the solid electrolyte, it is difficult to diffuse the polymer electrolyte into the semiconductor film, resulting in a decrease in photoelectric conversion efficiency. There was a case.
Further, only one type of photosensitizer capable of photoelectrically converting only visible light has been used for conventional semiconductor films. For this reason, only a part of light energy, that is, only light of a specific wavelength can be used, and further improvement has been demanded because it is not sufficient in terms of photoelectric conversion efficiency.
[0006]
Furthermore, conventionally, when forming a semiconductor film, particularly a metal oxide semiconductor film, a semiconductor film forming coating solution containing metal oxide particles is often applied by a spin coating method, a doctor blade method, a screen printing method, or the like. Was formed. However, in such a method, when a semiconductor film having a plurality of layers is formed, it is necessary to repeatedly apply the coating liquid for forming the semiconductor film a plurality of times by sequentially applying and drying. In addition, it is difficult to form a semiconductor film with complicated patterning, and even if it can, there is a problem in economic efficiency.
[0007]
OBJECT OF THE INVENTION
The present invention has been made in view of the above problems, and the utilization rate of optical energy is wide over a wide wavelength region (ultraviolet, visible, infrared region: wavelength 300 to 2000 nm) including ultraviolet and infrared regions in addition to visible light. The object is to provide a photoelectric cell having high photoelectric conversion efficiency, high photoelectric conversion efficiency, excellent economic efficiency, and even when a solid electrolyte is used.
[0008]
SUMMARY OF THE INVENTION
  The photovoltaic cell according to the present invention comprises:
  A substrate having an electrode layer (1) on the surface and a semiconductor film (2) having a photosensitizer adsorbed on the surface of the electrode layer (1), and a substrate having an electrode layer (3) on the surface Are arranged so that the electrode layer (1) and the electrode layer (3) face each other, and an electrolyte layer is provided between the semiconductor film (2) and the electrode layer (3). ,
  The semiconductor film (2) is a porous semiconductor film (2-A) having an average pore diameter in the range of 2 to 30 nm formed on the substrate, and an average pore diameter in the range of 30 to 400 nm formed thereon. A porous semiconductor film (2-B), and at least one substrate and the electrode layer on the substrate have transparencyHave
  The semiconductor film (2-A) contains an ultraviolet / short wavelength visible light absorption complex (A) as a photosensitizer, and the semiconductor film (2-B) absorbs a long wavelength visible light / infrared light as a photosensitizer. Contains complex (B)It is characterized by that.
[0009]
  The ultraviolet / short wavelength visible light absorbing complex (A) is preferably a dipyridyl-based ruthenium compound, and the long wavelength visible light / infrared absorbing complex (B) is preferably a tertiary pyridyl-based compound.
[0010]
The film thickness of the semiconductor film (2-A) is preferably in the range of 10 nm to 15 μm, and the film thickness of the semiconductor film (2-B) is preferably in the range of 0.5 to 15 μm.
Such semiconductor films (2-A) and (2-B) are preferably metal oxide semiconductor films,
The semiconductor film (2-A) and the semiconductor film (2-B) are preferably films formed by printing a coating liquid with an ink jet printer.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described.
[Photoelectric cell]
The photovoltaic cell according to the present invention comprises:
A substrate having an electrode layer (1) on the surface and a semiconductor film (2) having a photosensitizer adsorbed on the surface of the electrode layer (1);
A substrate having an electrode layer (3) on the surface,
The electrode layer (1) and the electrode layer (3) are arranged so as to face each other,
It is a photoelectric cell in which an electrolyte layer is provided between a semiconductor film (2) and an electrode layer (3).
[0012]
And in the present invention,
The semiconductor film (2) has a lower porous semiconductor film (2-A) having an average pore diameter in the range of 2 to 30 nm formed on the substrate and an average pore diameter of 30 to 400 nm formed thereon. And an upper porous semiconductor film (2-B) in the range.
In the present invention, the average pore diameter of the porous semiconductor film in contact with the electrolyte is large. Therefore, even when a solid electrolyte, that is, a polymer solid electrolyte is used, the polymer electrolyte can be easily diffused into the semiconductor film. As a result, the photoelectric conversion efficiency can be remarkably increased.
[0013]
An example of such a photoelectric cell is shown in FIG.
FIG. 1 is a schematic sectional view showing an embodiment of the photoelectric cell according to the present invention. In FIG. 1, the subscript 1 is a transparent electrode layer, 2 is a semiconductor film, and 2-A is a lower porous semiconductor. The film, 2-B is an upper porous semiconductor film, 3 is an electrode layer, 4 is an electrolyte layer, 5 is a transparent substrate, and 6 is a substrate. Specifically, the photoelectric cell shown in FIG. 1 has the transparent electrode layer 1 on the surface, and the average pore diameter in which the photosensitizer is adsorbed on the surface of the transparent electrode layer 1 is in the range of 2 to 30 nm. A lower porous semiconductor film (2-A) having a small pore diameter and an upper porous semiconductor film (2-B) having a large pore diameter in the range of 30 to 400 nm formed thereon are formed. A substrate 5 formed,
A substrate 6 having an electrode layer 3 having a catalytic reduction ability on the surface;
The electrode layers 1 and 3 are arranged to face each other,
Further, an electrolyte layer 4 in which an electrolyte is sealed is provided between the metal oxide semiconductor film 2 and the transparent electrode layer 3.
[0014]
As the transparent substrate 5, a transparent and insulating substrate such as a glass substrate or an organic polymer substrate such as PET can be used.
Further, the substrate 6 is not particularly limited as long as it has enough strength to withstand use. In addition to an insulating substrate such as an organic polymer substrate such as a glass substrate or PET, metal titanium, metal aluminum, metal copper, metal A conductive substrate such as nickel can be used.
[0015]
The transparent electrode layer 1 formed on the surface of the transparent substrate 5 includes tin oxide, tin oxide doped with Sb, F or P, indium oxide doped with Sn and / or F, antimony oxide, zinc oxide, noble metal, etc. Conventionally known electrodes such as can be used.
Such a transparent electrode layer 1 can be formed by a conventionally known method such as a thermal decomposition method or a CVD method.
[0016]
In addition, the electrode layer 3 formed on the surface of the substrate 6 is not particularly limited as long as it has a reduction catalytic ability, and may be an electrode material such as platinum, rhodium, ruthenium metal, ruthenium oxide, tin oxide, Conventionally known electrodes such as tin electrodes doped with Sb, F or P, electrodes obtained by plating or vapor-depositing the electrode materials on the surface of conductive materials such as indium oxide and Sn and / or F doped with antimony oxide, and carbon electrodes. An electrode can be used.
[0017]
The electrode layer 3 is formed by directly coating, plating, or vapor-depositing the electrode on the substrate 6 and forming a conductive layer from a conductive material by a conventionally known method such as a thermal decomposition method or a CDV method. The electrode material can be formed on the layer by a conventionally known method such as plating or vapor deposition.
The substrate 6 may be transparent like the transparent substrate 5, and the electrode layer 3 may be a transparent electrode like the transparent electrode layer 1.
[0018]
It is preferable that the transparent substrate 5 and the transparent electrode layer 1 have a higher transmittance of ultraviolet light, visible light, and infrared light, specifically 50% or more, particularly preferably 90% or more. When the ultraviolet light, visible light, and infrared light transmittance are less than 50%, the photoelectric conversion efficiency may be lowered.
The resistance values of the transparent electrode layer 1 and the electrode layer 3 are 100 Ω / cm, respectively.²The following is preferable. The resistance value of the electrode layer is 100Ω / cm²When the value exceeds the value, the photoelectric conversion efficiency may be lowered.
[0019]
The metal oxide semiconductor film 2 may be formed on the electrode layer 3 formed on the substrate 6. Of the metal oxide semiconductor film 2, the lower porous semiconductor film (2-A) preferably has a thickness in the range of 10 nm to 15 μm, more preferably 500 nm to 8 μm, and the upper porous semiconductor film (2-B ) Is preferably in the range of 0.5 to 15 μm, more preferably 2 to 8 μm.
[0020]
As the semiconductor film, an inorganic semiconductor film formed from an inorganic semiconductor material, an organic semiconductor film formed from an organic semiconductor material, an organic-inorganic hybrid semiconductor film, or the like can be used.
Examples of the organic semiconductor material include conventionally known compounds such as phthalocyanine, phthalocyanine-bisnaphthalocyanine, polyphenol, polyanthracene, polysilane, and polypyrrole.
[0021]
The semiconductor film 2 of the present invention is preferably an inorganic semiconductor film formed from an inorganic semiconductor material. Among these, the use of a metal oxide as the inorganic semiconductor material is preferable because a porous metal oxide semiconductor having a high photosensitizer adsorption amount can be obtained.
As such a metal oxide semiconductor film, at least one or two or more metal oxides selected from titanium oxide, lanthanum oxide, zirconium oxide, niobium oxide, tungsten oxide, strontium oxide, zinc oxide, tin oxide, and indium oxide are used. The metal oxide semiconductor film which consists of a thing can be mentioned.
[0022]
Such a metal oxide semiconductor film is usually composed of metal oxide particles and a binder component.
The metal oxide particles can be produced by a conventionally known method. Conventionally, using an inorganic compound salt or organometallic compound of the above metal, for example, adding an acid or alkali to a hydrous metal oxide gel or sol obtained by a sol-gel method, if necessary, followed by heating and aging It can be produced by a known method.
[0023]
Of the semiconductor film 2, the metal oxide contained in the lower porous semiconductor film (2-A) is a spherical particle having an average particle diameter in the range of 1 to 1000 nm, more preferably 8 to 100 nm. Is preferred. If the average particle diameter of the metal oxide particles is within the above range, a semiconductor film (2-A) having an average pore diameter described later can be formed.
The metal oxide contained in the upper porous semiconductor film (2-B) is not necessarily a spherical particle, but the average particle diameter is in the range of 50 to 1000 nm, more preferably 100 to 600 nm, and the lower porous layer The average particle diameter of the metal oxide particles used for the porous semiconductor film (2-A) is preferably larger.
[0024]
Specifically, the average particle diameter of the metal oxide particles contained in the lower porous semiconductor film (2-A) (D_A) And the average particle diameter of metal oxide particles contained in the upper porous semiconductor film (2-B) (D_B) (D)_B) / (D_A) Is 2-100, preferably 5-50.
Such large particles can scatter incident visible light and light having a longer wavelength than visible light, and can effectively photoelectrically convert the long wavelength light. Then, an upper porous semiconductor film (2-B) having an average pore diameter described later can be formed. If the average particle diameter of the metal oxide particles is within the above range, the semiconductor film (2-B) having the above average pore diameter can be formed, and the average fine particle of the upper porous semiconductor film (2-B) can be formed. If the pore diameter is within the above range, diffusion into the upper porous semiconductor film (2-B) such as an uncured polymer electrolyte polymer that is a raw material of an electrolyte, particularly a solid electrolyte, becomes possible. For this reason, the photoelectric cell which used solid electrolytes, such as a polymer electrolyte polymer, as an electrolyte layer which was difficult with the conventional photoelectric cell can be obtained.
[0025]
Further, the metal oxide particles contained in the lower porous semiconductor film (2-A) and the upper porous semiconductor film (2-B) are anatase-type titanium oxide, brookite-type titanium oxide, and rutile-type titanium oxide. Crystalline titanium oxide composed of seeds or two or more species is preferable. Crystalline titanium oxide has a high band gap, a high dielectric constant, a high adsorption amount of the photosensitizer compared to other metal oxide particles, and stability, safety, and easy film formation. Has excellent characteristics.
[0026]
Particles composed of such crystalline titanium oxide (hereinafter referred to as crystalline titanium oxide particles) are added to a hydrous titanic acid gel or sol obtained by a sol-gel method or the like, after adding an acid or an alkali, if necessary. It can be obtained by a conventionally known method such as heating and aging.
Further, the crystalline titanium oxide particles used in the present invention are obtained by adding hydrogen peroxide to a hydrous titanic acid gel or sol to dissolve the hydrous titanic acid to form peroxotitanic acid, and then adding the peroxotitanic acid to an alkali. Alternatively, it can be obtained by adding ammonia and / or an organic base to make it alkaline, and heating and aging in a temperature range of 80 to 350 ° C. Moreover, after adding the obtained crystalline titanium oxide particles as seed particles to peroxotitanic acid, the above step may be repeated.
[0027]
Furthermore, it can be fired at a high temperature of 350 ° C. or higher as necessary.
“Peroxotitanic acid” refers to hydrated titanium peroxide, and such titanium peroxide has absorption in the visible light region, and is an aqueous solution of a titanium compound, or a hydrated titanium oxide sol or Prepared by adding hydrogen peroxide to the gel and heating. The hydrated titanium oxide sol or gel is obtained by adding an acid or alkali to an aqueous solution of a titanium compound to hydrolyze it, and washing, heating and aging as necessary. Although there is no restriction | limiting in particular as a titanium compound used, Titanium compounds, such as titanium halides, such as a halogenated titanium and a titanyl sulfate, titanium alkoxides, such as tetraalkoxy titanium, and a titanium hydride can be used.
[0028]
In the present invention, in particular, as the crystalline titanium oxide particles, those obtained by adding alkali to peroxotitanic acid and heating and aging are preferably used.
The metal oxide semiconductor film contains a photosensitizer together with the metal oxide particles.
The photosensitizer is not particularly limited as long as it absorbs and excites light in the ultraviolet light region, visible light region, and infrared light region. For example, organic dyes, metal complexes, and the like can be used.
[0029]
As the organic dye, a conventionally known organic dye having a functional group such as a carboxyl group, a hydroxyalkyl group, a hydroxyl group, a sulfone group, a phosphate group, or a carboxyalkyl group in the molecule can be used. Specific examples include metal-free phthalocyanine, cyanine dyes, methocyanine dyes, triphenylmethane dyes, and xanthene dyes such as uranin, eosin, rose bengal, rhodamine B, and dibromofluorescein. In addition, merurochrome, merocyanine, riboflavin phosphate, tetrabromophenol blue, and tetrasulfophthalocyanine can also be used. These organic dyes have a characteristic that the adsorption rate to the (metal oxide) semiconductor film is fast.
[0030]
Examples of the metal complex include metal phthalocyanines such as copper phthalocyanine and titanyl phthalocyanine described in JP-A-1-220380 and JP-A-5-504023, chlorophyll, hemin, ruthenium-tris (2,2 ′ -Bispyridyl-4,4'-dicarboxylate), cis- (SCN^-Ruthenium- such as) -bis (2,2'-bipyridyl-4,4'-dicarboxylate) ruthenium, ruthenium-cis-diaqua-bis (2,2'-bipyridyl-4,4'-dicarboxylate) Examples of the complex include ruthenium, osmium, iron, zinc, platinum and the like, such as cis-diaqua-bipyridyl complex, porphyrin such as zinc-tetra (4-carboxyphenyl) porphine, and iron-hexocyanide complex. These metal complexes are excellent in the effect of spectral sensitization and durability.
[0031]
The organic dye or metal complex as the above-mentioned photosensitizer may be used alone, or may be used by mixing two or more kinds of organic dyes or metal complexes. Further, the organic dye and the metal complex are used in combination. Also good.
As a photosensitizer used in the photoelectric cell of the present invention, an organic dye or metal complex capable of photoelectrically converting ultraviolet light to visible light is used for the metal oxide particles used for the lower porous semiconductor film (2-A), As the metal oxide particles used for the upper porous semiconductor film (2-B), it is preferable to use an organic dye or a metal complex capable of photoelectrically converting visible light to infrared light.
[0032]
Examples of organic dyes or metal complexes that can photoelectrically convert visible light from ultraviolet light include dipyridyl-based ruthenium complexes, platinum complexes such as Pt (dcbpy = dcbipiridil) (gdt), merurochrome, merocyanine, eosin Y, riboflavin phosphate, Examples thereof include tetrabromophenol blue and tetrasulfophthalocyanine. Among them, dipyridyl-based ruthenium complexes are preferable, specifically, Ru (2,2bipiridil-4,4-dicarboxylate (TBA))₂(NCS)₂, Ru (dcbiphenyl)₂(NCS)₂, Ru (dcbpy)₂(β-diketonate), Ru (4,4'-dicarboxy-2,2'-bipiridine) [Ru (bipiridil)₂(CN)₂]₂, Ru (4,4'-dicarboxy-2,2'-bipiridine)₂, Ru (4,4'-dicarboxy-2,2'-bipiridine)₂(NCS)₂Is mentioned.
[0033]
Organic pigments or metal complexes that can convert visible to infrared light photoelectrically include tertiary pyridyl ruthenium complexes, ruthenium biquinoline, Ru (bpy)₂(CN)₂Etc. Among them, the tertiary pyridyl-based ruthenium complex is preferable, specifically, Ru (tc-terpyH_Three) (NCS)_Three, Ru (PO_Three-terpy) (Me₂bpy) (NCS), Ru (2,2 ', 2 ”-(COOH)_Three-terpy) (NCS)_ThreeEtc.
[0034]
The method of adsorbing the photosensitizer to each semiconductor film is not particularly limited, and the photosensitizer can be adsorbed by dispersing metal oxide particles in a solution obtained by dissolving the photosensitizer in a solvent. At this time, if necessary, the photosensitizer can be adsorbed by bringing the photosensitizer solution into contact with the semiconductor film while heating and refluxing. Moreover, you may make the photosensitizer adsorb | suck to the said metal oxide particle previously.
[0035]
The amount of the photosensitizer adsorbed on each semiconductor film is the unit surface area (1 cm) of the metal oxide semiconductor film.²) Is preferably 50 μg or more. When the amount of the photosensitizer is less than 50 μg, the photoelectric conversion efficiency may be insufficient.
In the present invention, it is desirable to adsorb the photosensitizer to the metal oxide particles in advance.
[0036]
The method for adsorbing the photosensitizer to the metal oxide particles is not particularly limited, and the photosensitizer can be adsorbed by dispersing the metal oxide particles in a solution obtained by dissolving the photosensitizer in a solvent. At this time, the photosensitizer can be adsorbed by contacting the particles while heating and refluxing the photosensitizer solution as necessary. Further, if necessary, it can be adsorbed under pressure.
[0037]
As the solvent for dissolving the photosensitizer, any solvent that dissolves the photosensitizer can be used. Specifically, water, alcohols, toluene, dimethylformamide, chloroform, ethyl cellosolve, N-methylpyrrolidone, Tetrahydrofuran or the like can be used.
The amount of the photosensitizer adsorbed on the metal oxide particles is determined by the unit surface area (1 cm) of the obtained metal oxide semiconductor film.²) Is preferably 50 μg or more. When the amount of the photosensitizer is less than 50 μg, the photoelectric conversion efficiency may be insufficient.
[0038]
Each porous semiconductor film preferably contains a titanium oxide binder component together with the metal oxide particles adsorbing the photosensitizer.
Examples of such titanium oxide binder components include hydrous titanic acid gels obtained by the sol-gel method or the like, titanium oxides composed of sols, and peroxo compounds in which hydrous titanic acid is dissolved by adding hydrogen peroxide to hydrous titanic acid gels or sols. Examples include decomposition products of titanic acid.
[0039]
Of these, a decomposition product of peroxotitanic acid is particularly preferably used.
Such a titanium oxide binder component has a function of improving the adhesion between the obtained metal oxide semiconductor film and the electrode. Furthermore, when such a titanium oxide binder component is used, contact between metal oxide particles is changed from point contact to surface contact, it is possible to improve electron mobility and increase photoelectric conversion efficiency.
[0040]
The ratio of the titanium oxide binder component to the metal oxide particles in each porous semiconductor film forming coating solution is the same as that of the titanium oxide binder component.₂The metal oxide particles are represented by MO_XWeight ratio TiO expressed as₂/ MO_XIs in the range of 0.03 to 0.50, preferably 0.1 to 0.3. When the weight ratio is less than 0.03, the contact between the metal oxide particles is insufficient, the effect of improving the photoelectric conversion efficiency is insufficient, and the adhesion between the obtained semiconductor film and the substrate is insufficient. When the weight ratio is higher than 0.50, a porous semiconductor film described later may not be obtained.
[0041]
The average pore diameter of the lower porous semiconductor film (2-A) is preferably in the range of 2 to 30 nm, more preferably 5 to 20 nm. If the average particle diameter of the metal oxide particles is within the above range, the semiconductor film (2-A) having the above average pore diameter can be formed, and the average fine particle of the lower porous semiconductor film (2-A) can be formed. When the pore diameter is in the above range, the photosensitizer can be adsorbed and the electrolyte can be diffused, and the electron mobility is not lowered. The lower porous semiconductor film (2-A) preferably has a pore volume in the range of 0.1 to 0.8 ml / g, more preferably 0.3 to 0.8 ml / g. When the pore volume is smaller than 0.1 ml / g, the electrolyte in the pores of the semiconductor film is insufficient, and the effective action ratio of the photosensitizer is reduced, so that sufficient photoelectric conversion efficiency cannot be obtained. In addition, if it exceeds 0.8 ml / g, the strength of the semiconductor film may be insufficient, and durability may not be obtained.
[0042]
The average pore diameter of the upper porous semiconductor film (2-B) is preferably in the range of 30 to 400 nm, more preferably 40 to 200 nm. If the average pore diameter of the upper porous semiconductor membrane (2-B) is in the above range, the upper porous semiconductor membrane (2-B) such as an uncured polymer electrolyte polymer that is a raw material of the electrolyte, particularly the solid electrolyte, is used. Diffusion becomes possible. For this reason, the photoelectric cell which used solid electrolytes, such as a polymer electrolyte polymer, as an electrolyte layer which was difficult with the conventional photoelectric cell can be obtained. When the average pore diameter is less than 30 nm, multiple scattering of light having a longer wavelength than visible light and visible light is insufficient, and the photoelectric conversion of light in this wavelength region tends to decrease. In addition, in the case of a cell using a solid electrolyte, the diffusion of the polymer electrolyte polymer before curing (solidification) into the pores becomes insufficient, so that sufficient photoelectric conversion efficiency may not be obtained. When the average pore diameter is higher than 400 nm, the electron mobility of the semiconductor film is lowered, and the photoelectric conversion efficiency may be lowered. The upper porous semiconductor film (2-B) preferably has a pore volume in the range of 0.1 to 0.8 ml / g, more preferably 0.3 to 0.8 ml / g. When the pore volume is smaller than 0.1 ml / g, the electrolyte in the pores is insufficient and the effective action ratio of the photosensitizer is lowered. When the pore volume is higher than 0.8 ml / g, the semiconductor is The electron mobility of the film may decrease, and the photoelectric conversion efficiency may decrease.
[0043]
Such a lower porous semiconductor film (2-A) and an upper porous semiconductor film (2-B) can be prepared using a specific coating liquid for forming a porous semiconductor film, respectively.
The coating liquid for forming a porous semiconductor film used in the present invention comprises the metal oxide particles and a dispersion medium. Furthermore, the precursor of a binder component can be included as needed.
[0044]
In the case where the metal oxide particles are crystalline titanium oxide particles, peroxotitanic acid is preferable as the precursor of the binder component.
Peroxotitanic acid is prepared by adding hydrogen peroxide to an aqueous solution of a titanium compound or a sol or gel of hydrated titanium oxide and heating.
The hydrated titanium oxide sol or gel is obtained by adding an acid or alkali to an aqueous solution of a titanium compound to hydrolyze it, and washing, heating and aging as necessary. Although there is no restriction | limiting in particular as a titanium compound used, Titanium compounds, such as titanium halides, such as a halogenated titanium and a titanyl sulfate, titanium alkoxides, such as tetraalkoxy titanium, and a titanium hydride can be used.
[0045]
The ratio of the titanium oxide binder component precursor to the metal oxide particles in the coating liquid for forming the porous semiconductor film is determined by changing the metal oxide binder component precursor to the oxide MO._XThe metal oxide particles represented by (1)_XWeight ratio (MO) as expressed by (2)_X(1) / MO_X(2)) should be in the range of 0.03 to 0.50, preferably 0.1 to 0.3. If the weight ratio is less than 0.03, the strength and conductivity of the semiconductor film may be insufficient, and the amount of adsorption of the photosensitizer may not increase. When the weight ratio is higher than 0.50, a porous semiconductor film may not be obtained, and the electron mobility may not be improved.
[0046]
Such a precursor of the metal oxide binder component and the metal oxide particles are contained in the coating liquid for forming a porous semiconductor film (MO_X(1) + MO_X(2)) is preferably contained in a concentration of 1 to 30% by weight, preferably 2 to 20% by weight.
The dispersion medium can be used without particular limitation as long as the precursor of the metal oxide binder component and the metal oxide particles can be dispersed and removed when dried, and alcohols are preferred among them. . In particular, when a film is formed by the ink jet printing method described later, it is not necessary to increase the viscosity of the coating liquid in order to improve the film forming property. On the contrary, it may be preferable that the viscosity is low from the viewpoint of nozzle clogging, etc., and the dispersion medium used for the coating liquid for forming a porous semiconductor film has a boiling point of about 40 ° C. or higher and a low viscosity coating. It is preferable to use a solvent from which a liquid can be obtained.
[0047]
Specific examples of such a solvent include terpineol.
Furthermore, the coating liquid for forming a porous semiconductor film may contain a film forming aid as required. Examples of the film forming aid used as necessary include polyethylene glycol, polyvinyl pyrrolidone, hydroxypropyl cellulose, polyacrylic acid, and polyvinyl alcohol. When such a film forming aid is contained in the coating solution, the viscosity of the coating solution increases, thereby obtaining a uniformly dried film, and the metal oxide particles are densely packed and bulky. A metal oxide semiconductor film with high density and high adhesion to the electrode can be obtained.
[0048]
The metal oxide semiconductor film is formed by applying the coating liquid for forming the lower porous semiconductor film (2-A) on the base material, and then applying the coating liquid for forming the upper porous semiconductor film (2-B) thereon. It can be formed by applying a liquid, drying and then curing.
The coating solution is preferably applied so that the film thicknesses of the lower porous semiconductor film (2-A) and the upper porous semiconductor film (2-B) to be finally formed are in the above-described ranges. As a coating method of the coating solution, it can be applied by a conventionally known method such as an ink jet method, a dipping method, a spinner method, a spray method, a roll coater method, flexographic printing, screen printing.
[0049]
In particular, in the inkjet method, two or more kinds of different coating liquids for forming a porous semiconductor film are simultaneously and vertically overlapped from different nozzles when forming two or more layers of porous semiconductor films as necessary. Can also be applied (printed). For this reason, since a multilayer film can be formed continuously, a film can be formed in a short time. Further, since a semiconductor film having an arbitrary patterning can be easily formed, the cost can be reduced.
[0050]
In the formation of the porous semiconductor film by the ink jet method, the film thickness can be adjusted by returning the discharge speed or the like.
When the porous semiconductor film is formed by the ink jet method, the viscosity of the coating solution used depends on the piezo element, but is preferably about 50 cp or less, more preferably 20 cp or less. When the viscosity of the coating liquid for forming a porous semiconductor film exceeds 50 cp, the discharge resistance from the piezo element increases, and the discharge speed may become uneven or clog.
[0051]
Next, the drying temperature at the time of drying is preferably a temperature range in which the dispersion medium can be removed and the photosensitizer adsorbed on the metal oxide particles is not desorbed or decomposed, and varies depending on the dispersion medium or the photosensitizer, but is generally 150 ° C. The following is preferable. At this time, pressurization can be performed as necessary. For example, adhesion with a base material or annealing described later may be promoted by pressurizing by a pressure roller method or the like.
[0052]
As long as the porous film is formed in two layers as described above, another porous film may be formed thereon.
In the present invention, the coating film can be further cured by irradiating with ultraviolet rays as necessary. By irradiating with ultraviolet rays, the precursor of the binder component can be decomposed and cured. In addition, when the film forming aid is contained in the coating liquid, the film forming aid may be decomposed by heat treatment after the coating film is cured.
[0053]
In the present invention, after the coating film is cured by ultraviolet irradiation, O₂, N₂, H₂Annealing may be performed after irradiation with ions of at least one gas selected from an inert gas belonging to Group 0 of the periodic table, such as neon, argon, and krypton.
As an ion irradiation method, a known method can be employed as a method of implanting boron or phosphorus into a silicon wafer to a certain amount and a certain depth when manufacturing an IC or LSI.
[0054]
In the present invention, annealing is performed by heating at 150 ° C. or lower for 10 minutes to 20 hours from the viewpoint of preventing decomposition of the photosensitizer. Annealing is performed by heating at a temperature range of 200 to 500 ° C., preferably 250 to 450 ° C., for 10 minutes to 20 hours.
Irradiation of ions of these gases does not leave these ions in the metal oxide semiconductor film, and many defects are generated on the surface of the metal oxide particles, improving the crystallinity of the metal oxide particles after annealing. At the same time, the bonding between the particles is promoted, so that the binding force with the photosensitizer is increased and the adsorption amount is increased, and further the electron mobility is improved by promoting the bonding of the particles, thereby improving the photoelectric conversion efficiency. There is a case.
[0055]
In the case of the semiconductor film used in the present invention, when the photosensitizer is not adsorbed in advance on the metal oxide particles, the porous semiconductor film forming coating containing the metal oxide particles not adsorbed with the photosensitizer After coating, drying and curing the liquid (2-A), the organic dye or metal complex capable of photoelectrically converting the above-described ultraviolet light to visible light is adsorbed, and then a coating liquid for forming a porous semiconductor film (2-A) is included. After coating, drying and curing, porous semiconductor film containing metal oxide particles that adsorb organic dye or metal complex capable of photoelectric conversion of the above-described ultraviolet light to visible light, and then do not adsorb photosensitizer After the coating liquid for formation (2-B) is applied, dried and cured, an organic dye or metal complex capable of photoelectrically converting infrared light from visible light may be adsorbed. Also, in the case of applying by an inkjet method, it may be simultaneously applied (printed) from a nozzle different from the application liquid and adsorbed to the porous film. As an adsorption method, a solution in which each photosensitizer is dissolved may be applied and dried. The application method is not particularly limited and can be applied by a conventionally known method. The drying temperature may be any temperature that can remove the dispersion medium.
[0056]
In the photoelectric cell according to the present invention, the semiconductor film 2 and the transparent electrode layer 3 are arranged to face each other, the side surfaces are sealed with a resin or the like, and the electrolyte layer 4 made of an electrolyte is provided between the electrodes. As the electrolyte, a mixture with at least one compound that forms a redox system with an electrochemically active salt is used.
Examples of the electrochemically active salt include quaternary ammonium salts such as tetrapropylammonium iodide. Compounds that form a redox system include quinone, hydroquinone, iodine (I^-/ I_Three ^-), Potassium iodide, bromine (Br)^-/ Br_Three ^-), Potassium bromide and the like. In some cases, these may be used in combination.
[0057]
The amount of such an electrolyte used varies depending on the type of electrolyte and the type of solvent described later, but the concentration in the mixture with the solvent to be used is within the range of about 0.1 to 5 mol / liter if necessary. Preferably there is.
As the solvent, conventionally known solvents can be used. Specifically, water, alcohols, oligoethers, carbonates such as propion carbonate, phosphate esters, dimethylformamide, dimethyl sulfoxide, N-methyl Examples include pyrrolidone, N-vinylpyrrolidone, sulfolane 66 sulfur compound, ethylene carbonate, acetonitrile, γ-butyrolactone, and the like.
[0058]
Furthermore, in the present invention, a solid electrolyte can be used as the electrolyte.
Examples of solid electrolytes include CuI, CuBr, CuSCN, polyaniline, polypyrrole, polythiophene, arylamine-based polymers, polymers having acrylic groups and / or methacrylic groups, polyvinylcarbazole, triphenyldiamine polymers, L-valine derivative low molecular gels, poly Oligoethylene glycol methacrylate, poly (o-methoxy aniline), poly (epichlorohydrin-Co-ethylene oxide), 2,2 ', 7,7'-tetorakis (N, N-di-P-methoxyphenyl-amine) -9, Fluorine ion exchange resins such as 9'-spirobifluorene and perfluorosulfonate, perfluorocarbon copolymers, perfluorocarbon sulfonic acids, etc., polyethylene oxide, and ionic cation methods such as imidazole cations And Br^-, BF_Four ^-, N^-(SO₂CF_Three)₂It is also possible to suitably use a material obtained by polymerizing a counter ion by adding a vinyl monomer and a PMMA monomer to the counter ion.
[0059]
When such a solid electrolyte is used, the electrolyte does not dissipate unlike the liquid electrolyte, and therefore the photoelectric conversion efficiency does not decrease even when used for a long time, and does not cause corrosion or the like.
[0060]
【The invention's effect】
According to the present invention, the utilization ratio of optical energy is high and the photoelectric conversion efficiency is high over a wide wavelength region (ultraviolet, visible, infrared region: wavelength 300 to 2000 nm) including ultraviolet and infrared regions in addition to visible light. Thus, a photoelectric cell excellent in economic efficiency can be obtained. In particular, when a solid electrolyte is used as the electrolyte, a photoelectric cell excellent in durability can be obtained without a decrease in photoelectric conversion efficiency over a long period of time.
[0061]
【Example】
Hereinafter, although an example explains, the present invention is not limited by these examples.
[0062]
[Example 1]
[Formation of porous semiconductor film (2-A-1)]
Titanium oxide particles ( A Preparation of
Suspend 5 g of titanium hydride in 1 liter of pure water, add 400 g of hydrogen peroxide solution with a concentration of 5% by weight over 30 minutes, then heat to 80 ° C to dissolve to prepare a solution of peroxotitanic acid. did. 90% by volume is taken from the total amount of this solution, adjusted to pH 9 by adding concentrated aqueous ammonia, placed in an autoclave, hydrothermally treated at 220 ° C. for 5 hours under saturated vapor pressure, and titania colloidal particles (A) Was prepared. The obtained titania colloidal particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0063]
Coating liquid for forming porous semiconductor film ( 2-A-1 Preparation of
Next, the titania colloidal particles (A) obtained above were solvent-substituted with high-boiling solvent terpineol and concentrated to a concentration of 10%, and the peroxotitanic acid solution was converted into oxides with respect to the titania particles. Weight ratio TiO₂(Particles) / TiO₂(Peroxotitanic acid) is mixed so that it becomes 9/1.₂Convert TiO₂Hydroxypropyl cellulose was added as a film formation aid so as to be 30% by weight of the weight to prepare a coating solution for forming a semiconductor film (2-A-1).
[0064]
Next, the coating solution is applied by screen printing on a transparent glass substrate on which fluorine-doped tin oxide is formed as an electrode layer, naturally dried, and subsequently 6000 mJ / cm using a low-pressure mercury lamp.²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. The coating film was heated at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose to form a porous semiconductor film (2-A-1).
[0065]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-A-1) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Spectral sensitizing dye adsorption(For ultraviolet and visible light)
Next, as a spectral sensitizing dye, cis- (SCN^-) -Bis (2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium (II) represented concentration of ruthenium complex (A-1) 3 × 10^-FourA mol / liter ethanol solution was prepared. This spectral sensitizing dye solution was applied onto the porous semiconductor film (2-A-1) using a spinner and dried. This coating and drying process was performed five times. Table 1 shows the amount of spectral sensitizing dye adsorbed on the obtained metal oxide semiconductor film.
[Formation of porous semiconductor film (2-B-1)]
Titanium oxide particles ( B Preparation of
Isopropoxide titanium and hydroxypropyl cellulose were dissolved in ethanol, and water was gradually added thereto to hydrolyze isopropoxide titanium. 90% by volume is taken from the total amount of this solution, adjusted to pH 9 by adding concentrated aqueous ammonia, put in an autoclave, hydrothermally treated at 250 ° C. for 5 hours under saturated vapor pressure, and titania particles (B). Prepared. The obtained titania particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0066]
Coating liquid for forming porous semiconductor film ( 2-B-1 Preparation of
Next, the titania particles (B) obtained above were solvent-substituted with terpineol and concentrated to a concentration of 10%, and the peroxotitanic acid solution was converted to oxide in terms of weight ratio TiO.₂(Particles) / TiO₂(Peroxotitanic acid) is mixed so that it becomes 9/1, and titanium in this mixed solution is changed to TiO.₂Convert TiO₂Hydroxypropyl cellulose was added as a film forming aid so as to be 30% by weight of the weight, to prepare a coating solution for forming a semiconductor film (2-B-1).
[0067]
Next, the coating solution is applied on the porous semiconductor film (2-A-1) by a screen method, naturally dried, and subsequently 6000 mJ / cm using a low-pressure mercury lamp.²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. The coating film was heated at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose to form an upper porous semiconductor film (2-B).
[0068]
  Table 1 shows the film thickness of the obtained porous semiconductor film (2-B-1) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
  Spectral sensitizing dye adsorption(For visible / infrared light)
  Next, as a spectral sensitizing dye, Ru (tc-terpyH3) (NCS)_Three The concentration of ruthenium complex (B-1) represented by the formula 3 × 10^-FourA mol / liter ethanol solution was prepared. Using this spectral sensitizing dye solution, rpm100 spinner,Porous semiconductor membrane (2-B)It was applied to the top and dried. This coating and drying process was performed five times. Table 1 shows the amount of spectral sensitizing dye adsorbed on the obtained metal oxide semiconductor film.
[0069]
Photoelectric cell (A) creation
Mix so that the volume ratio of acetonitrile to ethylene carbonate (acetonitrile: ethylene carbonate) is 1: 4, so that tetrapropylammonium iodide is 0.46 mol / liter and iodine is 0.06 mol / liter. To obtain an electrolyte layer mixture (A).
[0070]
The electrode prepared above is used as one electrode, and fluorine-doped tin oxide is formed as the other electrode. The transparent glass substrate carrying platinum is placed on the opposite side, and the sides are sealed with resin. The above electrolyte layer mixture (A) was sealed between the electrodes, and the electrodes were connected with lead wires to produce a photoelectric cell (A).
Photoelectric cell (A) is a solar simulator, 100 W / m²Irradiate light with an incident angle of 90 °, and measure Voc (voltage in an open circuit state), Joc (current density when the circuit is short-circuited), FF (curve factor), and η (conversion efficiency) did.
[0071]
The results are shown in Table 1.
[0072]
[Example 2]
[Formation of porous semiconductor film (2-A-2)]
Coating liquid for forming porous semiconductor film ( 2-A-2 Preparation of
The titania colloidal particles (A) obtained in the same manner as in Example 1 were substituted with ethyl cellosolve and concentrated to prepare 100 g of a 10% concentration dispersion, to which a ruthenium complex (A- 1) Concentration 3 × 10^-FourA spectral sensitizing dye is adsorbed on the titania colloidal particles (A) by adding 10 g of a mole / liter ethanol solution, and then the peroxotitanic acid solution is converted into oxides with respect to titania particles in a weight ratio TiO.₂(Particles) / TiO₂(Peroxotitanic acid) is mixed so that it becomes 9/1, a peroxotitanic acid solution is mixed, and then the titanium in this mixed solution is changed to TiO2.₂Convert TiO₂Hydroxypropyl cellulose was added as a film formation aid so as to be 30% by weight of the weight to prepare a coating solution for forming a semiconductor film (2-A-2).
[0073]
Next, the coating solution is filled in an ink cartridge, and this is printed and applied by an inkjet method (Epson Co., Ltd .: inkjet printer, MJ500C) on a transparent glass substrate on which fluorine-doped tin oxide is formed as an electrode layer. Air dry, then use a low pressure mercury lamp to 6000mJ / cm²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. The coating film was heated at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose to form a porous semiconductor film (2-A-2).
[0074]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-A-2) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
[Formation of porous semiconductor film (2-B-2)]
Coating liquid for forming porous semiconductor film ( 2-B-2 Preparation of
The titania particles (B) obtained in the same manner as in Example 1 were substituted with ethyl cellosolve and concentrated to prepare 100 g of a 10% concentration dispersion. To this, a ruthenium complex (B-1 ) Concentration 3 × 10^-FourA spectral sensitizing dye is adsorbed to titania particles (B) by adding 10 g of a mol / liter ethanol solution, and then the peroxotitanic acid solution is converted into an oxide in a weight ratio TiO.₂(Particles) / TiO₂(Peroxotitanic acid) is mixed so that it becomes 9/1, and titanium in this mixed solution is changed to TiO.₂Convert TiO₂Hydroxypropyl cellulose was added as a film forming aid so as to be 30% by weight of the weight to prepare a coating solution for forming a semiconductor film (2-B-2).
[0075]
Next, the coating solution is filled in an ink cartridge, and this is printed and applied by an inkjet method (Epson Co., Ltd .: inkjet printer, MJ500C) on a transparent glass substrate on which fluorine-doped tin oxide is formed as an electrode layer. Air dry, then use a low pressure mercury lamp to 6000mJ / cm²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. Subsequently, the coating film was annealed by applying a heat roller at 60 ° C. for 30 minutes to form a porous semiconductor film (2-B-2).
[0076]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-B-2) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Photoelectric cell (B) creation
In Example 1, instead of the porous semiconductor film (2-A-1) and the porous semiconductor film (2-B-1), the porous semiconductor film (2-A-2) and the porous semiconductor film (2-B A photoelectric cell (B) was prepared in the same manner as in Example 1 except that -2) was used.
[0077]
For the photoelectric cell (B), Voc, Joc, FF and η were measured. The results are shown in the table.
[0078]
[Example 3]
[Formation of porous semiconductor film (2-A-3)]
Titanium oxide particles ( C Preparation of
Suspend 5 g of titanium hydride in 1 liter of pure water, add 400 g of hydrogen peroxide solution with a concentration of 5% by weight over 30 minutes, then heat to 80 ° C to dissolve to prepare a solution of peroxotitanic acid. did. 90% by volume was taken from the total amount of this solution, adjusted to pH 10 by adding concentrated aqueous ammonia, placed in an autoclave, hydrothermally treated at 250 ° C. for 15 hours under saturated vapor pressure, and titania colloidal particles (C) Was prepared. The obtained titania colloidal particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0079]
Coating liquid for forming porous semiconductor film ( 2-A-3 Preparation of
Next, a coating solution for forming a semiconductor film (2-A-3) was prepared in the same manner as in Example 1 except that the titania colloidal particles (C) obtained above were used.
Next, a porous semiconductor film (2-A-3) was formed in the same manner as in Example 2 (by the ink jet method) using the coating liquid for forming a semiconductor film (2-A-3).
[0080]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-A-3) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
[Formation of porous semiconductor film (2-B-3)]
Titanium oxide particles ( D Preparation of
Suspend 5 g of titanium hydride in 1 liter of pure water, add 400 g of hydrogen peroxide solution with a concentration of 5% by weight over 30 minutes, then heat to 80 ° C to dissolve to prepare a solution of peroxotitanic acid. did. 90% by volume was taken from the total amount of this solution, adjusted to pH 9 by adding concentrated aqueous ammonia, placed in an autoclave, hydrothermally treated at 250 ° C. for 5 hours under saturated vapor pressure, and titania particles (D) were removed. Prepared. The obtained titania colloidal particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0081]
Coating liquid for forming porous semiconductor film ( 2-B-3 Preparation of
Next, a coating solution for forming a semiconductor film (2-B-3) was prepared in the same manner as in Example 1 except that the titania particles (D) obtained above were used.
Next, a porous semiconductor film (2-B-3) was formed by the inkjet method using the coating liquid for forming a semiconductor film (2-B-3) in the same manner as in Example 2.
[0082]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-B-3) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Photoelectric cell (C) creation
In Example 1, instead of the porous semiconductor film (2-A-1) and the porous semiconductor film (2-B-1), the porous semiconductor film (2-A-3) and the porous semiconductor film (2-B A photoelectric cell (C) was prepared in the same manner as in Example 1 except that -3) was used.
[0083]
For the photoelectric cell (C), Voc, Joc, FF and η were measured. The results are shown in Table 1.
[0084]
[Example 4]
Creation of photoelectric cell (D)
In Example 2, a bipyridyl ruthenium complex (A-2) · [Ru (dc-bpyH as a spectral sensitizer on a titania colloidal particle (A).₂)₂(NCS)₂] And adsorbed onto the titania particles (B-1) as a spectral sensitizer with a tertiary pyridylruthenium complex (B-2) ・ (Ru (tc-terpyH_Three) (NCS)_Three) Was adsorbed to produce a photoelectric cell (D) in the same manner as in Example 2.
[0085]
For the photoelectric cell (D), Voc, Joc, FF and η were measured. The results are shown in the table.
[0086]
[Example 5]
Photoelectric cell (E) creation
In Example 3, one electrode substrate on which a semiconductor film is formed is placed on a hot plate, and a CuI solution in which 0.6 g of CuI is dissolved in 20 ml of dehydrated acetonitrile is uniformly dropped onto the electrode substrate to a thickness of about 25 μm. A solid electrolyte layer is formed, this is used as one electrode, and fluorine doped tin oxide is formed as the other electrode as an electrode, and a transparent glass substrate carrying platinum thereon is placed opposite to it, and the side is made of resin. Then, the photoelectric cells (E) were prepared by connecting the electrodes with lead wires.
[0087]
For the photoelectric cell (E), Voc, Joc, FF and η were measured. The results are shown in the table.
[0088]
[Comparative Example 1]
Porous semiconductor film (2-A) only
In the same manner as in Example 1, a coating solution for forming a semiconductor film (2-A-1) was prepared.
Next, the coating solution is applied by screen printing on a transparent glass substrate on which fluorine-doped tin oxide is formed as an electrode layer, naturally dried, and subsequently 6000 mJ / cm using a low-pressure mercury lamp.²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. The coating film was heated at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose to form a porous semiconductor film (2-A-4).
[0089]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-A-4) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Spectral sensitizing dye adsorption
Next, the spectral sensitizing dye (A-1) solution used in Example 1 was applied onto the porous semiconductor film (2-A-4) using an rpm 100 spinner and dried. This coating and drying process was performed five times. Table 1 shows the amount of spectral sensitizing dye adsorbed on the obtained metal oxide semiconductor film.
[0090]
Creation of photoelectric cell (F)
The electrode prepared above is used as one electrode, and fluorine-doped tin oxide is formed as the other electrode. The transparent glass substrate carrying platinum is placed on the opposite side, and the sides are sealed with resin. The electrolyte layer mixture (A) used in Example 1 was sealed between the electrodes, and the electrodes were connected with lead wires to produce a photoelectric cell (F).
[0091]
For the photoelectric cell (F), Voc, Joc, FF and η were measured. The results are shown in Table 1.
[0092]
[Comparative Example 2]
Porous semiconductor film (2-B) only
In the same manner as in Example 1, a coating solution for forming a semiconductor film (2-B-1) was prepared.
Next, the coating solution is applied by screen printing on a transparent glass substrate on which fluorine-doped tin oxide is formed as an electrode layer, naturally dried, and subsequently 6000 mJ / cm using a low-pressure mercury lamp.²The ultraviolet rays were irradiated to decompose the peroxoacid and the coating was cured. The coating film was heated at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose to form a porous semiconductor film (2-B-4).
[0093]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-B-4) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Spectral sensitizing dye adsorption
Next, the spectral sensitizing dye (B-1) solution used in Example 1 was applied onto the porous semiconductor film (2-B-4) using an rpm 100 spinner and dried. This coating and drying process was performed five times. Table 1 shows the amount of spectral sensitizing dye adsorbed on the obtained metal oxide semiconductor film.
[0094]
Creation of photoelectric cell (G)
The electrode prepared above is used as one electrode, and fluorine doped tin oxide as the other electrode is formed as an electrode. A transparent glass substrate carrying platinum is placed on the opposite side, and the side is sealed with resin. The electrolyte layer mixture (A) used in Example 1 was sealed between the electrodes, and the electrodes were connected with lead wires to produce a photoelectric cell (G).
[0095]
For the photoelectric cell (G), Voc, Joc, FF and η were measured. The results are shown in Table 1.
[0096]
[Comparative Example 3]
[Formation of porous semiconductor film (2-A-5)]
Preparation of titanium oxide particles (E)
Suspend 5 g of titanium hydride in 1 liter of pure water, add 400 g of hydrogen peroxide solution with a concentration of 5% by weight over 30 minutes, then heat to 80 ° C to dissolve to prepare a solution of peroxotitanic acid. did. 90% by volume is taken from the total amount of this solution, adjusted to pH 8 by adding concentrated aqueous ammonia, placed in an autoclave, hydrothermally treated at 180 ° C. for 5 hours under saturated vapor pressure, and titania colloidal particles (E) Was prepared. The obtained titania colloidal particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0097]
Coating liquid for forming porous semiconductor film ( 2-A-5 Preparation of
Next, a coating solution for forming a semiconductor film (2-A-5) was prepared in the same manner as in Example 2 except that the titania colloidal particles (E) obtained above were used.
Next, a porous semiconductor film (2-A-5) was formed in the same manner as in Example 2 using the coating liquid for forming a semiconductor film (2-A-5).
[0098]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-A-5) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
[Formation of porous semiconductor film (2-B-5)]
Titanium oxide particles ( F Preparation of
Suspend 5 g of titanium hydride in 1 liter of pure water, add 400 g of hydrogen peroxide solution with a concentration of 5% by weight over 30 minutes, then heat to 80 ° C to dissolve to prepare a solution of peroxotitanic acid. did. 90% by volume is taken from the total amount of this solution, adjusted to pH 9 by adding concentrated aqueous ammonia, placed in an autoclave, hydrothermally treated at 250 ° C. for 2 hours under saturated vapor pressure, and titania colloidal particles (F) Was prepared. The obtained titania colloidal particles were anatase type titanium oxide having high crystallinity by X-ray diffraction. Table 1 shows the average particle diameter of the anatase-type titanium oxide particles.
[0099]
Coating liquid for forming porous semiconductor film ( 2-B-5 Preparation of
Next, a coating solution for forming a semiconductor film (2-B-5) was prepared in the same manner as in Example 2 except that the titania colloidal particles (F) obtained above were used.
Next, a porous semiconductor film (2-B-5) was formed in the same manner as in Example 2 using the coating liquid for forming a semiconductor film (2-B-5).
[0100]
Table 1 shows the film thickness of the obtained porous semiconductor film (2-B-5) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Creation of photoelectric cell (H)
The electrode prepared above is used as one electrode, and fluorine doped tin oxide as the other electrode is formed as an electrode. A transparent glass substrate carrying platinum is placed on the opposite side, and the side is sealed with resin. The electrolyte layer mixture (A) used in Example 1 was sealed between the electrodes, and the electrodes were connected with lead wires to produce a photoelectric cell (H).
[0101]
For the photoelectric cell (H), Voc, Joc, FF and η were measured. The results are shown in Table 1.
[0102]
[Table 1]

[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing an embodiment of a photoelectric cell according to the present invention.
[Explanation of symbols]
1 ... Transparent electrode layer
2 ... Semiconductor film
2-A: Lower porous semiconductor film
2-B… Upper porous semiconductor film
3 ... Electrode layer
4 ... electrolyte layer
5 ... Transparent substrate
6 ... Board

Claims (5)

A substrate having an electrode layer (1) on the surface and a semiconductor film (2) having a photosensitizer adsorbed on the surface of the electrode layer (1), and a substrate having an electrode layer (3) on the surface Are arranged so that the electrode layer (1) and the electrode layer (3) face each other, and an electrolyte layer is provided between the semiconductor film (2) and the electrode layer (3). ,
The semiconductor film (2) is a porous semiconductor film (2-A) having an average pore diameter in the range of 2 to 30 nm formed on the substrate, and an average pore diameter in the range of 30 to 400 nm formed thereon. It becomes because the porous semiconductor film (2-B) in the electrode layer of at least one of the substrate and the substrate has a transparency,
The semiconductor film (2-A) contains an ultraviolet / short wavelength visible light absorption complex (A) as a photosensitizer, and the semiconductor film (2-B) absorbs a long wavelength visible light / infrared light as a photosensitizer. A photoelectric cell comprising a complex (B) .   The ultraviolet / short wavelength visible light absorbing complex (A) is a dipyridyl ruthenium compound, and the long wavelength visible light / infrared absorbing complex (B) is a tertiary pyridyl compound. Photovoltaic cell.   The film thickness of the semiconductor film (2-A) is in the range of 10 nm to 15 µm, and the film thickness of the semiconductor film (2-B) is in the range of 0.5 to 15 µm. 3. The photoelectric cell according to 2.   4. The photoelectric cell according to claim 1, wherein the semiconductor films (2-A) and (2-B) are metal oxide semiconductor films.   The light according to any one of claims 1 to 4, wherein the semiconductor film (2-A) and the semiconductor film (2-B) are films formed by printing a coating liquid with an ink jet printer. Electric cell.

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