JP4100863B2 - Photoelectric cell - Google Patents

Description

【図面の簡単な説明】
【図１】 本発明の光電気セルの一実施例の模式断面図を示す。
【符号の説明】
１０……光電気セル
１１……透明電極層
１２……半導体膜
１３……表面に還元触媒能を有する電極層
１４……電解質
１５……可視光反射防止膜
１６……紫外線遮蔽膜
P-1、P-2……基板[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a photovoltaic cell that converts light energy into electrical energy and extracts it. More specifically, the present invention relates to light that has a high visible light utilization rate and that can stably maintain high photoelectric conversion efficiency over a long period of time. It relates to an electric cell.
[0002]
TECHNICAL BACKGROUND OF THE INVENTION
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 such a 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. Since this photoelectric energy conversion occurs continuously, it is used, for example, in solar cells.
[0003]
In general solar cells, a semiconductor film for a photoelectric conversion material is first formed on a support such as a glass plate on which a transparent conductive film is formed, and then another transparent conductive film is used as a counter electrode. A support such as a formed glass plate is provided, and an electrolyte is sealed between these electrodes.
When the photosensitizer adsorbed on the semiconductor for photoelectric conversion material is irradiated with sunlight, the photosensitizer 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 photosensitizer that has moved electrons 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. In this way, electrons flow continuously, and the photoelectric conversion material functions as a solar cell.
[0004]
As this photoelectric conversion material, a material obtained by adsorbing a spectral sensitizing dye having absorption in the visible light region on the semiconductor surface is used. For example, Japanese Patent Application Laid-Open No. 1-220380 describes a solar cell having a spectral sensitizing dye layer made of a transition metal complex such as a ruthenium complex on the surface of a metal oxide semiconductor layer. Japanese Patent Publication No. 5-504023 describes a solar cell having a spectral sensitizing dye layer made of a transition metal complex such as a ruthenium complex on the surface of a titanium oxide semiconductor layer doped with metal ions.
[0005]
In such a solar cell, the electrolyte may be dissolved in a solvent and used as an electrolytic solution. An organic solvent such as alcohol may be used as the solvent at this time, and an organic electrolyte is used as the electrolyte. Sometimes.
However, in such a solar cell, when used for a long period of time, the electrolyte or solvent may deteriorate or deteriorate, the electrolytic solution itself may leak, and the photosensitizer may be detached or decomposed. Therefore, there has been a problem that the photoelectric conversion efficiency is lowered. Moreover, since performance is not necessarily sufficient depending on a use, it is calculated | required to raise the utilization factor and conversion efficiency of sunlight further.
[0006]
Under such circumstances, the present inventors have intensively studied to solve the above problems, and as a result, by forming a visible light antireflection film and / or an ultraviolet shielding film on the outer surface of the substrate, the above problems can be solved. The inventors have found that a photoelectric cell in which all the points are eliminated can be obtained, and have completed the present invention.
[0007]
OBJECT OF THE INVENTION
The present invention has a high utilization factor of visible light, and does not deteriorate the photosensitizer, the organic electrolyte, the organic solvent for dissolving the electrolyte, and the like. Therefore, light that can stably maintain high photoelectric conversion efficiency and the like over a long period of time. It aims to provide an electric cell.
[0008]
SUMMARY OF THE INVENTION
The photovoltaic cell according to the present invention comprises:
A substrate (P-1) comprising a metal oxide semiconductor film (2) having an electrode layer (1) on the surface and adsorbing a photosensitizer on the surface of the electrode layer (1);
A substrate (P-2) 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,
At least one of the substrate and the electrode layer has transparency,
In the photoelectric cell in which the electrolyte layer is provided between the metal oxide semiconductor film (2) and the electrode layer (3),
A visible light antireflection film and / or an ultraviolet shielding film is formed on the outer surface of at least one of the transparent substrate (P-1) and / or the substrate (P-2).
[0009]
The purple ultraviolet shielding film is formed on the outer surface of the transparent substrate (P-1), a visible light antireflection film is formed on the ultraviolet shielding film, and
The refractive index of the visible light antireflection film is preferably lower than the refractive index of the ultraviolet shielding film.
The ultraviolet shielding film is one or more metal oxide particles selected from the group consisting of Ce, Fe, Ti, Sb, Zr, Zn, or from the group consisting of Ce, Fe, Ti, Sb, Zr, Zn. It is preferable to comprise composite oxide particles of two or more kinds of metals selected.
[0010]
The visible light antireflection film is obtained by applying and drying a visible light antireflection film-forming coating solution, followed by heat treatment,
It is preferable that the ultraviolet shielding film is obtained by applying and drying an ultraviolet shielding film-forming coating solution, followed by heat treatment.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The photoelectric cell according to the present invention will be specifically described below.
[Photoelectric cell]
The photovoltaic cell according to the present invention comprises:
A substrate (P-1) comprising a metal oxide semiconductor film (2) having an electrode layer (1) on the surface and adsorbing a photosensitizer on the surface of the electrode layer (1);
A substrate (P-2) 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,
At least one of the substrate and the electrode layer has transparency,
In the photoelectric cell in which the electrolyte layer is provided between the metal oxide semiconductor film (2) and the electrode layer (3),
A visible light antireflection film and / or an ultraviolet shielding film is formed on the outer surface of at least one of the transparent substrate (P-1) and / or the substrate (P-2).
[0012]
An example of such a photoelectric cell is shown in FIG.
FIG. 1 is a schematic sectional view showing an embodiment of a photoelectric cell 10 according to the present invention.
A substrate (P-1) having a transparent electrode layer 11 on the surface and a semiconductor film 12 having a photosensitizer adsorbed on the surface of the transparent electrode layer 11, and an electrode layer having a reduction catalytic ability on the surface A substrate (P-2) having 13 is disposed so that the electrode layers 11 and 13 face each other.
[0013]
An electrolyte 14 is sealed between the metal oxide semiconductor film 12 and the electrode layer 13,
An ultraviolet shielding film 16 is formed on the outer surface of at least one of the transparent substrates (P-1), and a visible light antireflection film 15 is further formed on the surface of the ultraviolet shielding film 16.
[0014]
As the transparent substrate (P-1), a transparent and insulating substrate such as a glass substrate or an organic polymer substrate such as PET can be used.
The substrate (P-2) is not particularly limited as long as it has enough strength to withstand use. In addition to transparent insulating substrates such as glass substrates and organic polymer substrates such as PET, metallic titanium, metallic aluminum, metallic copper A conductive substrate such as metallic nickel can be used.
[0015]
Furthermore, a deformable substrate such as a PET film is used as the transparent substrate (P-1) and the substrate (P-2) by interposing a spacer between the metal oxide semiconductor film 12 and the electrode layer 13. Moreover, it can be set as the photoelectric cell of shapes other than flat form, for example, semicylindrical shape. In this case, for example, it is possible to obtain a flexible photoelectric cell or the like that is transparent or thin and has an arbitrary shape.
[0016]
The transparent electrode layer 11 formed on the surface of the transparent substrate (P-1) includes tin oxide, tin oxide doped with Sb, F or P, indium oxide doped with Sn and / or F, antimony oxide, oxidation Conventionally known electrodes such as zinc and noble metals can be used.
Such a transparent electrode layer 11 can be formed by a conventionally known method such as a thermal decomposition method or a CVD method.
[0017]
In addition, the electrode layer 13 formed on the surface of the substrate (P-2) is not particularly limited as long as it has a reduction catalytic ability, and electrode materials such as platinum, rhodium, ruthenium metal, ruthenium oxide and the like. An electrode obtained by plating or vapor-depositing the electrode material on the surface of a conductive material such as tin oxide, tin oxide doped with Sb, F or P, indium oxide doped with Sn and / or F, or antimony oxide, a carbon electrode A conventionally well-known electrode can be used.
[0018]
The electrode layer 13 is formed by directly coating, plating, or vapor-depositing the electrode on the substrate (P-2), and forming a conductive layer by a conventionally known method such as a thermal decomposition method or a CDV method. Thereafter, the electrode material can be formed on the conductive layer by a conventionally known method such as plating or vapor deposition.
The substrate (P-2) may be transparent like the transparent substrate (P-1), and the electrode layer 13 may be a transparent electrode like the transparent electrode layer 11.
[0019]
The visible light transmittance of the transparent substrate (P-1) and the transparent electrode layer 11 is preferably higher, specifically 50% or more, particularly preferably 90% or more. When the visible light transmittance is less than 50%, the photoelectric conversion efficiency may be lowered.
The resistance values of the transparent electrode layer 11 and the electrode layer 13 are 100 Ω / cm, respectively.²The following is preferable. The resistance value of the electrode layer is 100 Ω / cm²When the value exceeds the value, the photoelectric conversion efficiency may be lowered.
[0020]
The metal oxide semiconductor film 12 is formed on the transparent electrode layer 11 formed on the substrate (P-1). The metal oxide semiconductor film 12 may be formed on the electrode layer 13 formed on the substrate (P-2). The film thickness of such a metal oxide semiconductor film 12 is preferably in the range of 0.1 to 50 μm.
Examples of such a metal oxide semiconductor film include 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. The metal oxide semiconductor film which consists of a thing can be mentioned.
[0021]
The metal oxide particles constituting such a metal oxide semiconductor film 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.
[0022]
The average particle diameter of the metal oxide particles is 5 to 600 nm, preferably 10 to 300 nm. The particle diameter of the metal oxide particles can be measured with a laser Doppler particle size measuring instrument (manufactured by Nikkiso Co., Ltd .: Microtrac).
If the average particle diameter of the metal oxide particles is less than 5 nm, cracks are likely to occur in the formed metal oxide semiconductor film, and it may be difficult to form a thick film without cracks in a small number of times. Furthermore, the pore diameter and pore volume of the metal oxide semiconductor film may decrease, and the amount of adsorption of the photosensitizer may decrease. In addition, when the average particle diameter of the metal oxide particles is larger than 600 nm, the strength of the metal oxide semiconductor film may be insufficient.
[0023]
Furthermore, the metal oxide particles are preferably crystalline titanium oxide composed of one or more of anatase type titanium oxide, brookite type titanium oxide, and rutile type titanium oxide. Such crystalline titanium oxide has a high band gap and a high dielectric constant, and the adsorption amount of the photosensitizer is higher than other metal oxide particles, and further, stability, safety, and film formation are easy. There are some excellent properties.
[0024]
The metal oxide semiconductor film 12 preferably contains a titanium oxide binder component together with the metal oxide particles.
Examples of such a titanium oxide binder component include a hydrous titanic acid gel obtained by a sol-gel method or the like, a titanium oxide composed of a sol, or a hydrous titanic acid gel or sol to which hydrogen peroxide is added to dissolve the hydrous titanic acid. Examples include a decomposition product of luoxotitanic acid.
[0025]
“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.
[0026]
The ratio of the titanium oxide binder component to the metal oxide particles in the metal oxide semiconductor film 12 is 0.05 to 0.50, preferably 0 in terms of weight ratio in terms of oxide (titanium oxide binder component / metal oxide particles). It is desirable to be in the range of 0.1 to 0.3. When the weight ratio is less than 0.05, the absorption of light in the visible light region is insufficient, and the amount of adsorption of the photosensitizer may not increase. When the weight ratio is higher than 0.50, a porous metal oxide semiconductor film may not be obtained, and the amount of adsorption of the photosensitizer may not be increased.
[0027]
The metal oxide semiconductor film 12 preferably has a pore volume of 0.05 to 0.8 ml / g and an average pore diameter of 2 to 250 nm. When the pore volume is smaller than 0.05 ml / g, the adsorption amount of the photosensitizer is low, and when it is higher than 0.8 ml / g, the electron mobility in the film is lowered and the photoelectric conversion efficiency is improved. May decrease. Further, when the average pore diameter is less than 2 nm, the adsorption amount of the photosensitizer decreases, and when it exceeds 250 nm, the electron mobility decreases and the photoelectric conversion efficiency may decrease.
[0028]
In the present invention, an inorganic semiconductor film formed from another inorganic semiconductor material, an organic semiconductor film formed from an organic semiconductor material, an organic-inorganic hybrid semiconductor film, or the like is used as the semiconductor film instead of the metal oxide. it can.
For example, examples of the organic semiconductor material include conventionally known compounds such as phthalocyanine, phthalocyanine-bisnaphthalocyanine, polyphenol, polyanthracene, polysilane, polypyrrole, and polyaniline.
[0029]
Next, in the present invention, the metal oxide semiconductor film 12 adsorbs the photosensitizer.
The photosensitizer is not particularly limited as long as it absorbs and excites light in the visible light region and / or infrared light region. For example, organic dyes, metal complexes, and the like can be used.
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, or a carboxyalkyl group in the molecule can be used. Specific examples include metal-free phthalocyanines, cyanine dyes, methocyanine dyes, triphenylmethane dyes, and xanthene dyes such as uranin, eosin, rose bengal, rhodamine B, and dibromofluorescein. 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 thereof include complexes of ruthenium, osmium, iron, zinc and the like, such as cis-diaqua-bipyridyl complexes, porphyrins such as zinc-tetra (4-carboxyphenyl) porphine, and iron-hexacyanide complexes. 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, and further used in combination with an organic dye and a metal complex. Also good.
The adsorption method of such a photosensitizer is not particularly limited, and a solution obtained by dissolving the photosensitizer in a solvent is absorbed into the metal oxide semiconductor film by a method such as a dipping method, a spinner method, a spray method, Next, a general method such as drying can be employed. Furthermore, you may repeat the said absorption process as needed. Alternatively, the photosensitizer can be adsorbed to the metal oxide semiconductor film by bringing the photosensitizer solution into contact with the substrate while heating and refluxing.
[0032]
The solvent for dissolving the photosensitizer may be any solvent that can dissolve the photosensitizer, and specifically water, alcohols, toluene, dimethylformamide, chloroform, ethyl cellosolve, N-methylpyrrolidone. , Tetrahydrofuran and the like can be used.
The amount of photosensitizer adsorbed on the metal oxide semiconductor film is 1 cm of the specific surface area of the metal oxide semiconductor film.²It is preferably 50 μg or more per unit. When the amount of the photosensitizer is less than 50 μg, the photoelectric conversion efficiency may be insufficient.
[0033]
In the photoelectric cell according to the present invention, the semiconductor film 12 and the transparent electrode layer 13 (the semiconductor film and the electrode layer when the semiconductor film is formed on the surface of the transparent electrode layer) are arranged to face each other, and the side surface is made of resin. And the like, and an electrolyte layer 14 made of an electrolyte and a liquid crystal is sealed 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.
[0034]
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.
[0035]
In the present invention, a liquid crystal is used as needed together with the electrolyte.
The liquid crystal is not particularly limited as long as the photosensitizer adsorbed on the semiconductor film has a low solubility so that the photosensitizer does not desorb and dissolve, and a conventionally known liquid crystal can be used. .
As such a liquid crystal, a conventionally known smectic liquid crystal, nematic liquid crystal, cholesteric liquid crystal or the like can be used as a temperature transition type liquid crystal.
[0036]
Further, a concentration transition type liquid crystal, a polymer liquid crystal, a polymer dispersed liquid crystal, a disk-like liquid crystal, or the like can be used. Among these, when a liquid crystal compound containing a fluorine atom is used, it is highly hydrophobic and excellent in long-term stability.
Moreover, the solvent may be contained with the liquid crystal. As the solvent, a solvent having a low solubility of the photosensitizer so that the photosensitizer adsorbed on the metal oxide semiconductor film does not desorb and dissolve is desirable. Specific examples of such solvents include water, alcohols, oligoethers, carbonates such as propion carbonate, phosphate esters, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, N-vinylpyrrolidone, and sulfolane 66. Sulfur compounds, ethylene carbonate, acetonitrile, γ-butyrolactone and the like can be mentioned.
[0037]
Furthermore, as a solvent, for example, an organic polymerizing (gelling) agent such as a mixture of a vinyl monomer and a divinyl monomer, a reactive monomer such as an N-methylol compound or dicarboxylic acid can be used. Using such a reactive monomer as a solvent, the electrolyte is dissolved and the cell is formed, and then the monomer is cured, so that the electrolyte can be solidified or gelled. Can be suppressed.
[0038]
The concentration of the electrochemically active salt in such an electrolyte layer is not particularly limited, and is usually 1 liter of a liquid crystal compound (the total of the liquid crystal compound and the solvent if a solvent is included) It is desirable to be in the range of 0.01 to 5 mol / liter, preferably 0.1 to 2 mol / liter. If the concentration of the electrochemically active salt is less than 0.01 mol / liter, the concentration is too low, so that the ability to exchange electrons with the photosensitizer or the electrode decreases, and the photoelectric conversion efficiency decreases. Sometimes. When the concentration exceeds 5 mol / liter, the electrochemically active salt may not dissolve in the liquid crystal compound and the solvent.
[0039]
The concentration of the compound that forms the redox system is not particularly limited, and is usually 0.01 to 5 with respect to 1 liter of the liquid crystal compound (the total of the liquid crystal compound and the solvent when a solvent is included). It is desirable to be in the range of mol / liter, preferably 0.1-2 mol / liter. If the concentration of the compound that forms the redox system is less than 0.01 mol / liter, the concentration is too low, so that the ability to exchange electrons with the photosensitizer or the electrode decreases, and the photoelectric conversion efficiency decreases. Sometimes. Further, even when the concentration exceeds 5 mol / liter, the electron transfer capability is not further increased, and therefore the photoelectric conversion efficiency is not improved. Further, when the concentration exceeds 5 mol / liter, long-term stability may be lowered.
[0040]
The molar ratio of the compound forming the redox system and the electrochemically active salt in the electrolyte (compound forming the redox system / electrochemically active salt) is in the range of 1/20 to 3/10. It is preferable that it exists in.
If a solvent is included, the solvent volume (V_S) And volume of liquid crystal (V_LC) And volume (V_S/ V_LC) Ratio is 1.0 or less, preferably 0.75 or less. If the volume ratio exceeds 1.0, the proportion of liquid crystal is small, so that the effect of the light energy utilization rate due to the light scattering effect described above becomes insufficient, and long-term stability may not be improved.
[0041]
The photoelectric cell according to the present invention has a transparent electrode layer 11 on the surface and a substrate 5 on which a semiconductor film 12 having adsorbed a photosensitizer is formed on the surface of the electrode layer 11, and a reduction catalytic ability on the surface. The substrate 6 having the electrode layer 13 is disposed so that the metal oxide semiconductor film 12 and the electrode layer 13 face each other, the side surfaces are sealed with a resin, and the metal oxide semiconductor film 12 and the electrode layer 13 are An electrolyte, a liquid crystal, and optionally a liquid crystal or a solvent are sealed between the electrodes, and the electrodes are connected by lead wires.
[0042]
In the photoelectric cell according to the present invention as described above, when the liquid crystal is included in the electrolyte layer, the amount of received light is not greatly reduced by the light scattering effect of the liquid crystal even when the incident angle of light increases. The light energy can be stably converted into electric energy and extracted. In addition, the light reflected by the semiconductor film without being involved in the excitation of the photosensitizer in the incident light is again irradiated to the photosensitizer in the semiconductor film and converted into electrical energy by the light scattering effect of the liquid crystal. Therefore, the conversion efficiency of light energy can be increased. Furthermore, when liquid crystal having hydrophobicity is used as the liquid crystal, the hygroscopic action is reduced as compared with the case where only the hygroscopic electrolyte is used. Therefore, deterioration due to decomposition of the electrolyte, photosensitizer, or solvent due to moisture absorption. As a result, an effect of improving long-term stability is obtained.
[0043]
In the photoelectric cell according to the present invention, spacer particles may be interposed between the metal oxide semiconductor film and the electrode layer as necessary. Alternatively, spacer particles may be embedded in the semiconductor film, and at least a part of the spacer particles may be exposed from the semiconductor film so as to be in contact with the electrode layer.
Note that in the case where a metal oxide semiconductor film is formed on the surface of the electrode layer, spacer particles may be interposed between the opposing transparent electrode layer and the metal semiconductor film.
[0044]
At this time, the spacer particles are not particularly limited as long as the metal oxide semiconductor film and the electrode layer are not damaged and do not contact each other, and spherical spacer particles, rod-shaped spacer particles, and the like can be used. Conventionally known insulating particles made of plastic), organic-inorganic composites, metal oxides, ceramics, or the like can be used. In particular, when the spacer particles 7 are interposed, a photoelectric cell in which the distance between the metal oxide semiconductor film 12 and the electrode layer 13 is as small as about 1 to 50 μm can be suitably obtained.
[0045]
Examples of the resin spacer particles include resin particles disclosed in Japanese Patent Publication No. 7-95165.
As the spacer particles of the organic-inorganic composite, particles obtained by hydrolyzing metal alkoxides disclosed in JP-A-7-140472 and JP-B-8-25739 can be suitably used.
[0046]
As the metal oxide or ceramic spacer particles, spherical particles disclosed in JP-A-3-218915 and JP-B-7-64548 can be suitably used.
Furthermore, particles obtained by fusing a synthetic resin on the surface of each particle described above can also be suitably used. As such particles, for example, resin-coated particles disclosed in JP-A-63-94224 can be suitably used. In particular, particles coated with an adhesive resin are fixed by adhering to the metal oxide semiconductor film and / or electrode layer, and can effectively exhibit uniform gap adjustment or stress absorption without moving.
[0047]
An ultraviolet shielding film 16 is formed on the outer surface of the transparent substrate (P-1), and a visible light antireflection film 15 is formed on the surface of the ultraviolet shielding film 16.
In the present invention, not only the photoelectric cell shown in FIG. 1, but any one of the antireflection film and the ultraviolet shielding film is formed on the outer surface of the transparent substrate (P-1) or the substrate (P-2). Good. Further, the antireflection film itself may be a laminated film composed of two or more antireflection films, or the ultraviolet shielding film itself may be a laminated film composed of two or more antireflection films. A laminated film in which a plurality of shielding films are laminated may be used.
[0048]
More preferably, an ultraviolet shielding film is formed on the outer surface of the transparent substrate (P-1), and an antireflection film is formed on the ultraviolet shielding film surface.
Note that the antireflection film has a higher refractive index than the ultraviolet shielding film and the antireflection film, and the difference in refractive index between the ultraviolet shielding film and the antireflection film is approximately 0.3 or more, more preferably 0.6 or more. It is desirable. When the difference in refractive index is less than 0.3, the antireflection performance is insufficient.
[0049]
  More preferably, an ultraviolet shielding film is formed on the outer surface of the transparent substrate (P-1), and an antireflection film is formed on the ultraviolet shielding film surface.
  Note that the refractive index of the antireflection film is higher than that of the ultraviolet shielding film and the antireflection film.LowThe difference in refractive index between the ultraviolet shielding film and the antireflection film is preferably about 0.3 or more, more preferably 0.6 or more. When the difference in refractive index is less than 0.3, the antireflection performance is insufficient.
[0050]
matrix
The antireflection film matrix used in the present invention is not particularly limited as long as the obtained antireflection film has transparency, has a lower refractive index than the underlying substrate or ultraviolet shielding film, and has antireflection performance. Is an inorganic oxide such as silica, titania, zirconia, or a composite oxide or polyester resin thereof, acrylic resin, urethane resin, vinyl chloride resin, epoxy resin, melamine resin, fluorine resin, silicon resin, butyral resin, phenol resin , Vinyl acetate resins, ultraviolet curable resins, electron beam curable resins, and the like, and resins for coating such as copolymers and modified products of these resins. These can be selected and used in consideration of the type of substrate, adhesion, hardness, coatability and the like.
[0051]
Among these, a matrix made of silica is preferable, and a hydrolyzable organosilicon compound partial hydrolyzate, hydrolyzed polycondensate, or a portion of a silicic acid solution obtained by dealkalizing an aqueous alkali metal silicate solution. A silica matrix composed of a hydrolyzate and a hydrolyzed polycondensate is preferred, and a silica matrix derived from an alkoxysilane hydrolyzed polycondensate represented by the following general formula [1] is particularly preferred.
[0052]
R_aSi (OR ')_4-a            [1]
(In the formula, R is a vinyl group, an aryl group, an acrylic group, an alkyl group having 1 to 8 carbon atoms, a hydrogen atom or a halogen atom, and R ′ is a vinyl group, an aryl group, an acrylic group, or a carbon system having 1 to 8 carbon atoms. An alkyl group, -C₂H_FourOC_nH_{2n + 1}(N = 1 to 4) or a hydrogen atom, and a is an integer of 0 to 3. )
Such alkoxysilanes include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraoctylsilane, methyltrimethoxysilane, methyltriethoxysilane, ethyltriethoxysilane, methyltriisopropoxysilane, Examples include vinyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane.
Inorganic compound particles
The antireflection film may contain inorganic compound particles as necessary. As such, the refractive index is 1.60 or less, preferably 1.50 or less, and the average particle size is 5 to 5. Oxide fine particles or composite oxide fine particles in the range of 300 nm can be suitably used.
[0053]
As such particles, silica-based colloidal particles disclosed in JP-A-5-132309, JP-A-7-133105, JP-A-10-194721, JP-A-10-45403, etc. by the applicant of the present application are used. It can be used suitably.
In particular, among the composite oxide fine particles, silica and inorganic oxides other than silica, porous core particles or cavities, and a silica coating layer having a thickness in the range of 1 to 50 nm.₂Inorganic oxides other than silica_xMolar ratio MO expressed as_x/ SiO₂Are in the range of 0.0001 to 0.3 and the average particle diameter is in the range of 5 to 300 nm, the refractive index is usually as low as 1.40 or less. The antireflective film containing the material has a refractive index of 1.43 or less and has excellent antireflection performance.
[0054]
When the average particle size of the inorganic compound particles used in the present invention is less than 5 nm, the effect of improving the adhesion with the substrate or the ultraviolet ray prevention film described later cannot be sufficiently obtained, and the average particle size exceeds 300 nm. The transparency of the antireflection film may be reduced, or cracks may occur in the film. That is, when the average particle diameter of the inorganic compound particles is in the above range, an antireflection film having excellent adhesion to a substrate and the like and excellent film strength can be obtained.
[0055]
The film thickness of such an antireflection film is preferably in the range of 50 to 500 nm, preferably 80 to 300 nm.
When the film thickness of the antireflection film exceeds 500 nm, the antireflection film is too thick, the light transmittance is lowered, the transparency is deteriorated, and the appearance is also deteriorated.
Such an antireflection film is formed by using the antireflection film forming coating liquid (1) or (2) shown below.
[0056]
(1) Coating liquid for antireflection film formation
When the above-described resin is used as the matrix, an antireflection film-forming coating liquid (1) in which the antireflection film-forming matrix and, if necessary, the inorganic compound particles are dissolved or dispersed in water and / or an organic solvent is used. Use.
[0057]
The weight ratio between the inorganic compound particles and the matrix in the coating liquid (1) for forming the antireflection film is desirably in the range of inorganic compound particles / matrix = 1/99 to 9/1. When the weight ratio exceeds 9/1, the strength of the formed antireflection film is insufficient and lacks practicality, while when it is less than 1/99, it is difficult to form an antireflection film excellent in adhesion and strength.
[0058]
(2) Coating liquid for antireflection film formation
When an inorganic oxide such as silica, titania or zirconia, or a composite oxide thereof is used as a matrix, a silicon compound such as alkoxysilane, halogenated silane, or silicic acid, a titanium compound such as titanium alkoxide or titanium tetrachloride, A matrix precursor dispersion is prepared by hydrolyzing and polycondensing one or more of Zr and Zn compounds such as zirconium alkoxide in the presence of an acid or base catalyst in water and / or an organic solvent. The inorganic compound particles are mixed with the matrix precursor dispersion as necessary to obtain a coating solution for forming an antireflection film.
[0059]
The concentration of the matrix precursor contained in the coating solution thus obtained is preferably in the range of 0.05 to 10% by weight in terms of oxide. Particularly preferred is the range of 0.2 to 5.0% by weight.
When the concentration of the matrix precursor contained in the coating solution is less than 0.05% by weight, the resulting film is thin and may have poor chemical resistance and antireflection performance. A film with a sufficient film thickness may not be obtained, and a film with a uniform film thickness may not be obtained even when coating is repeated.
[0060]
If the concentration of the matrix precursor exceeds 10% by weight, the resulting film may be cracked or the strength of the film may be reduced. In addition, the film may be too thick and the antireflection performance may be insufficient.
The molecular weight of such a matrix precursor is preferably in the range of 500 to 10,000 in terms of polystyrene, and particularly preferably in the range of 700 to 2,500.
[0061]
When the molecular weight in terms of polystyrene is less than 500, an unhydrolyzed product may be present in the coating solution, and the coating may not be performed uniformly. Even if it is applied, it may be inferior in adhesion to the lower layer. When the molecular weight in terms of polystyrene exceeds 10,000, the strength of the coating tends to decrease.
Moreover, it is preferable that the density | concentration of the inorganic compound particle used as needed in a coating liquid exists in the range of 0.05-3 weight% in conversion of an oxide. Especially preferably, it is 0.2 to 2 weight% of range.
[0062]
When the concentration of the inorganic compound particles contained in the coating solution is less than 0.05% by weight, the refractive index of the antireflection film obtained when the amount of the inorganic compound particles is too small is not sufficiently low and the antireflection performance may be inferior. In addition, when the concentration of the inorganic compound particles exceeds 3% by weight, the resulting film may be cracked or the strength of the film may be reduced.
Furthermore, the antireflection film-forming coating solutions (1) and (2) used in the present invention include fine particles composed of a low refractive index material such as magnesium fluoride, transparency of the antireflection film and antireflection performance. A small amount of conductive fine particles and / or additives such as dyes or pigments may be contained to such an extent that they do not hinder.
[0063]
Formation of antireflection film
The method for forming the antireflection film is not particularly limited, and is a dry thin film forming method such as a vacuum evaporation method, a sputtering method, or an ion plating method, or a dipping method, a spinner method, a spray method, a roll coater method, a flexographic printing method, etc. It is possible to employ a wet thin film forming method that is applied and then dried.
[0064]
Among these, the wet thin film forming method is preferable because an antireflection film can be formed at low cost.
The thickness of the antireflection film obtained is preferably in the range of 50 to 500 nm, preferably 80 to 300 nm.
When the film thickness of the antireflection film is less than 50 nm, the film strength, chemical resistance, antireflection performance, etc. may be inferior.
[0065]
When the thickness of the antireflection film exceeds 500 nm, cracks may occur in the film or the strength of the film may decrease, and the film may be too thick and the antireflection performance may be insufficient.
When the film thickness is in the above range, the film strength and scratch resistance are excellent, and excellent antireflection performance is exhibited. For this reason, the photoelectric cell has a high utilization rate of sunlight and can obtain high photoelectric conversion efficiency.
[0066]
In the present invention, a film formed by applying such an antireflection film-forming coating solution is heated at 100 ° C. or higher at the time of drying or after drying, or an uncured film has a wavelength shorter than that of visible light. Irradiate electromagnetic waves such as ultraviolet rays, electron beams, X-rays and γ rays. When such heat treatment, ultraviolet irradiation, electromagnetic wave irradiation, or the like is performed, the curing of the matrix precursor is promoted and the hardness of the resulting antireflection film is increased.
[0067]
[Ultraviolet shielding film]
The ultraviolet shielding film is composed of an ultraviolet shielding film forming matrix and one or more metal oxide particles selected from the group consisting of Ce, Fe, Ti, Sb, Zr, and Zn, or Ce, Fe, Ti, Sb, and Zr. And composite oxide particles of two or more metals selected from the group consisting of Zn.
[0068]
Matrix for UV shielding film
The matrix for the ultraviolet ray shielding film used in the present invention is not particularly limited as long as the obtained ultraviolet ray shielding film has transparency and adhesion to the coated surface, and is the same as the matrix for the antireflection film. Can be mentioned.
Specifically, inorganic oxides such as silica, titania and zirconia, or composite oxides or polyester resins thereof, acrylic resins, urethane resins, vinyl chloride resins, epoxy resins, melamine resins, fluororesins, silicone resins, butyral resins Examples thereof include phenol resins, vinyl acetate resins, ultraviolet curable resins, electron beam curable resins, and coating resins such as copolymers and modified products of these resins. These can be appropriately selected and used in consideration of the type of substrate and the like, adhesion, hardness, coatability and the like.
[0069]
UV shielding particles
As the ultraviolet shielding particles, one or more metal oxide particles selected from the group consisting of Ce, Fe, Ti, Sb, Zr, and Zn, or from the group consisting of Ce, Fe, Ti, Sb, Zr, and Zn. Two or more kinds of metal composite oxide particles selected are used. These particles have an ultraviolet shielding ability and a high refractive index of 1.8 or more, so that the obtained ultraviolet shielding film has a high refractive index and therefore has a high antireflection performance.
[0070]
As such ultraviolet shielding particles, colloidal particles disclosed in JP-A-10-182152, JP-A-2-178219, JP-A-62-283817 and the like by the applicant of the present application can be suitably used. .
Such ultraviolet shielding particles preferably have an average particle diameter in the range of 5 to 500 nm. A more preferable range is 5 to 200 nm. When the average particle diameter of the ultraviolet shielding particles is less than 5 nm, the effect of improving the adhesion to the substrate cannot be obtained sufficiently, and when the average particle diameter exceeds 500 nm, the transparency of the ultraviolet shielding film decreases. Cracks may occur in the film. When the average particle diameter of the ultraviolet shielding particles is within the above range, an ultraviolet shielding film having excellent adhesion to a substrate and the like and excellent film strength can be obtained.
[0071]
The proportion of the ultraviolet shielding particles in the ultraviolet shielding film is preferably in the range of 1 to 99% by weight. A more preferable range is 30 to 80% by weight.
When the proportion of the ultraviolet shielding particles in the ultraviolet shielding film is less than 1% by weight, the ultraviolet shielding effect and the effect of improving the adhesion to the substrate cannot be sufficiently obtained, and when it exceeds 99% by weight, the strength of the film is insufficient. May be sufficient.
[0072]
Such an ultraviolet shielding film is formed using the coating liquid for forming an ultraviolet shielding film (1) or (2) shown below.
(1) UV shielding film forming coating solution
When the above-described resin is used as the matrix, an ultraviolet shielding film forming coating solution (1) in which the matrix and the ultraviolet shielding particles are dissolved or dispersed in water and / or an organic solvent is used.
[0073]
The weight ratio between the ultraviolet shielding particles and the matrix in the ultraviolet shielding film-forming coating solution (1) is preferably in the range of ultraviolet shielding particles / matrix = 1/99 to 9/1. If the weight ratio exceeds 9/1, the strength of the film is insufficient and lacks practicality, while if it is less than 1/99, it is difficult to form an ultraviolet shielding film excellent in adhesion to the substrate and strength.
(2) UV shielding film forming coating solution
When an inorganic oxide such as silica, titania, zirconia, or a composite oxide thereof is used as a matrix, a silicon compound such as alkoxysilane, halogenated silane, or silicic acid, a titanium compound such as titanium alkoxide or titanium tetrachloride, A matrix precursor dispersion is prepared by hydrolyzing one or more of salts of Zr and Zn compounds such as zirconium alkoxide in the presence of an acid or base catalyst in water and / or an organic solvent, and then preparing this matrix. If necessary, the ultraviolet light shielding particles are mixed with the precursor dispersion to obtain a coating liquid for forming an ultraviolet light shielding film.
[0074]
The concentration of the matrix precursor contained in the coating solution thus obtained is preferably in the range of 0.05 to 10% by weight in terms of oxide. Particularly preferred is the range of 0.2 to 5.0% by weight.
The concentration of the matrix precursor contained in the coating solution thus obtained is preferably in the range of 0.05 to 10% by weight in terms of oxide. Particularly preferred is the range of 0.2 to 5.0% by weight.
[0075]
When the concentration of the matrix precursor contained in the coating solution is less than 0.05% by weight, a film having a sufficient film thickness may not be obtained by one coating, and a uniform film can be obtained even by repeated coating. A thick film may not be obtained.
If the concentration of the matrix precursor exceeds 10% by weight, the resulting film may be cracked or the strength of the film may be reduced. Moreover, the film thickness of the obtained film tends to be non-uniform, or the surface flatness tends to be lacking.
[0076]
Moreover, it is preferable that the density | concentration of the particle | grains for ultraviolet shielding in a coating liquid exists in the range of 0.05-30 weight% in conversion of an oxide. Particularly preferably, it is in the range of 1 to 10% by weight.
When the concentration of the ultraviolet shielding particles contained in the coating solution is less than 1% by weight, the ultraviolet shielding ability of the ultraviolet shielding film obtained when the amount of the ultraviolet shielding particles is too small may be inferior. If the concentration exceeds 30% by weight, the resulting film may be cracked or the strength of the film may be reduced.
[0077]
Furthermore, in the coating liquids (1) and (2) for forming an ultraviolet shielding film used in the present invention, a small amount of conductive fine particles and / or dyes or dyes are used so as not to inhibit the transparency and ultraviolet shielding effect of the ultraviolet shielding film. Additives such as pigments may be included.
Formation of UV shielding film
As a method of forming the ultraviolet shielding film, a wet thin film forming method of applying and drying by a method such as a dipping method, a spinner method, a spray method, a roll coater method, or a flexographic printing method can be suitably employed.
[0078]
At this time, the film thickness of the obtained ultraviolet shielding film is 10 to 500 nm, preferably 50 to 200 nm.
When the film thickness of the ultraviolet shielding film is less than 10 nm, the strength of the film, the ultraviolet shielding ability, etc. may decrease, or the visible light low reflectivity may be insufficient.
If the film thickness of the ultraviolet shielding film exceeds 500 nm, cracks may occur in the film or the film strength may decrease, and the film may be too thick and the low visible light reflectivity may be insufficient.
[0079]
When the film thickness is in the above range, the film strength is excellent and an excellent ultraviolet shielding ability is exhibited. For this reason, even if the photoelectric cell is used for a long period of time, the electrolyte or solvent does not deteriorate or deteriorate, or deteriorates and leaks, and the spectral sensitizing dye is not desorbed or deteriorated. High photoelectric conversion efficiency (performance) can be maintained for a long time.
[0080]
In the present invention, a film formed by applying such a coating solution for forming an anti-ultraviolet film is heated at 100 ° C. or higher at the time of drying or after drying, or an uncured film has a wavelength shorter than that of visible light. Electromagnetic waves such as ultraviolet rays, electron beams, X-rays, and γ rays can be irradiated. By such treatment, the curing of the matrix precursor is promoted, and the hardness of the resulting UV protection film is increased.
[0081]
When the visible light antireflection film is formed on the outer surface of the substrate, the photoelectric cell according to the present invention as described above obtains a photoelectric cell having a large incident light in the irradiated visible light and a high visible light utilization rate. be able to. In addition, when an ultraviolet shielding film is formed, the electrolyte or solvent does not deteriorate or deteriorate even if it is used for a long time, and it does not deteriorate due to deterioration, and the spectral sensitizing dye is desorbed or deteriorated. There is nothing. For this reason, according to this invention, the photoelectric cell which can maintain high photoelectric conversion efficiency (performance) for a long period of time can be obtained.
[0082]
The visible light antireflection film and / or the ultraviolet shielding film can be formed by using an antireflection film forming coating solution and / or an ultraviolet shielding film forming coating solution. Such a film is excellent in film strength, adhesion to a substrate, transparency and the like, and can be formed at low cost.
[0083]
【The invention's effect】
According to the present invention, it is possible to obtain a photoelectric cell having a high visible light utilization rate because of a large amount of incident light in the irradiated visible light, and the electrolyte or solvent deteriorates or deteriorates even when used for a long time. A photoelectric cell that can maintain high photoelectric conversion efficiency (performance) for a long period of time without degrading and leaking without desorbing or degrading the spectral sensitizing dye can be obtained.
[0084]
【Example】
Hereinafter, although an example explains, the present invention is not limited by these examples.
[0085]
[Example 1]
Preparation of matrix precursor dispersion
Orthoethyl silicate (TEOS) (SiO₂: 28 wt%) 50 g of ethanol, 194.6 g of ethanol, 1.4 g of concentrated nitric acid, and 34 g of pure water were stirred at room temperature for 5 hours, and SiO 2₂A matrix precursor dispersion having a concentration of 5% by weight was prepared.
[0086]
Preparation of coating solution for UV shielding film formation
100 g of the above-mentioned matrix precursor dispersion is mixed with 100 g of titanium oxide colloid (manufactured by Catalyst Kasei Kogyo Co., Ltd .: HPW-15R, average particle diameter 15 nm, concentration 30 wt%) as an ultraviolet shielding particle. Liquid (A) was prepared.
Preparation of coating solution for forming visible light antireflection film
First, inorganic compound particles having a hollow inside were prepared as follows.
[0087]
Average particle size 5nm, SiO₂A reaction mother liquor was prepared by mixing 10 g of silica sol having a concentration of 20% by weight and 190 g of pure water, and heated to 95 ° C. The pH of this reaction mother liquor was 10.5. In this reaction mother liquor, SiO₂24,900 g of a sodium silicate aqueous solution having a concentration of 1.5% by weight in terms of₂O_ThreeIn addition, 36,800 g of a sodium aluminate aqueous solution having a concentration of 0.5% by weight was added at the same time. Meanwhile, the temperature of the reaction solution was maintained at 95 ° C. The pH of the reaction solution rose to 12.5 immediately after the addition of sodium silicate and sodium aluminate, and hardly changed thereafter.
[0088]
After completion of the addition, the reaction solution is cooled to room temperature, washed with an ultrafiltration membrane, and a SiO 2 having a solid content concentration of 20% by weight.₂・ Al₂O_ThreeA dispersion of porous material precursor particles was prepared.
Next, 500 g of this porous material precursor particle dispersion is sampled, 1,700 g of pure water is added and heated to 98 ° C., and the aqueous sodium silicate solution is removed with a cation exchange resin while maintaining this temperature. Silicic acid solution obtained by alkali (SiO₂A silica protective film was formed on the surface of the porous material precursor particles by adding 3,000 g (concentration: 3.5 wt%). The obtained dispersion of porous material precursor particles was washed with an ultrafiltration membrane to adjust the solid content concentration to 13% by weight, and then 1125 g of pure water was added to 500 g of the dispersion of porous material precursor particles. In addition, concentrated hydrochloric acid (35.5%) was added dropwise to adjust the pH to 1.0, and after dealumination treatment, aluminum salt dissolved in the ultrafiltration membrane was added while adding 10 L of hydrochloric acid aqueous solution of pH 3 and 5 L of pure water. Separated to prepare a particle precursor dispersion.
[0089]
A mixture of 1500 g of the particle precursor dispersion, 500 g of pure water, 1,750 g of ethanol, and 626 g of 28% ammonia water was heated to 35 ° C., and then ethyl silicate (SiO₂: 28 wt%) 104 g was added, and a silica outer shell layer was formed on the surface of the particle precursor with a hydrolyzed polycondensate of ethyl silicate to prepare particles having cavities inside the outer shell layer. Next, after concentration to a solid content concentration of 5% by weight with an evaporator, ammonia water with a concentration of 15% by weight is added to adjust the pH to 10, and heat treatment is performed at 180 ° C. for 2 hours in an autoclave, and the dispersion medium is ethanol using an ultrafiltration membrane. A dispersion liquid of inorganic compound particles having a solid content concentration of 20% by weight and a hollow inside was prepared.
[0090]
The cross section of the obtained particles was observed with a transmission electron microscope (TEM). As a result, particles having cavities formed in the outer shell layer were obtained. Also, Al of this particle₂O_Three/ SiO₂The molar ratio was 0.0022, the average particle size was 96 nm, and the refractive index was 1.31. Next, the previously prepared SiO₂A mixed solvent of ethanol / butanol / diacetone alcohol / isopropyl alcohol (2: 1: 1: 5 weight mixing ratio) is added to a 5% by weight matrix precursor dispersion, and the inorganic compound particle dispersion prepared above is added. Concentration of inorganic compound particles is 0.2% by weight, matrix precursor SiO₂A coating solution (A) for forming a visible light antireflection film having a concentration of 1% by weight was prepared.
[0091]
Preparation of glass substrate with UV shielding film and visible light antireflection film
While maintaining a transparent glass substrate formed with fluorine-doped tin oxide as an electrode at 40 ° C., an ultraviolet shielding film-forming coating solution (A) is applied to the opposite surface of the electrode at 100 rpm for 90 seconds by a spinner method. The ultraviolet shielding film was applied and dried so that the film thickness was 120 nm.
[0092]
Next, on the ultraviolet shielding film, similarly, the spinner method was applied at 100 rpm for 90 seconds so that the thickness of the visible light antireflection film was 100 nm, dried, and heat-treated at 160 ° C. for 30 minutes. Thus, a glass substrate (A) with an ultraviolet shielding film and a visible light antireflection film was prepared.
The reflectance of the glass substrate (A) with an ultraviolet shielding film and a visible light antireflection film was measured using a reflectometer (manufactured by Otsuka Electronics Co., Ltd .: MCPD-2000). The reflectance at the wavelength having the lowest reflectance in the wavelength range of 400 to 700 nm was defined as the bottom reflectance, and the average reflectance in the wavelength range of 400 to 700 nm was defined as the luminous reflectance.
[0093]
The results are shown in Table 1.
Preparation of metal oxide particles for semiconductor films
5 g of titanium hydride was suspended in 1 L of pure water, 400 g of 5% hydrogen peroxide solution was added over 30 minutes, and then heated to 80 ° C. to dissolve to prepare a solution of peroxotitanic acid. Concentrated aqueous ammonia was added thereto to adjust the pH to 9, and the mixture was placed in an autoclave and subjected to hydrothermal treatment at 250 ° C. for 5 hours under saturated vapor pressure to prepare titania colloidal particles (A). It was anatase type titanium oxide having high crystallinity by X-ray diffraction. The average particle size was 40 nm.
[0094]
Preparation of coating solution for semiconductor film formation
Next, the titania colloidal particles (A) obtained above are concentrated to a concentration of 10%, and the peroxotitanic acid solution is mixed therewith, and the titanium in the mixture is converted into TiO2.₂A coating solution for forming a semiconductor film was prepared by adding hydroxypropylcellulose, which is a film forming aid, so as to be 30% by weight of the weight when converted to.
[0095]
Formation of semiconductor film
Next, it was applied on the electrode surface of the transparent glass substrate with the electrode on which the ultraviolet ray shielding film and the visible light antireflection film were formed, naturally dried, and subsequently 6000 mJ / cm using a low pressure mercury lamp.²Was irradiated with UV light to decompose perhydrotitanic acid (hydrolysis and polycondensation) to cure the semiconductor film. Furthermore, the titanium oxide semiconductor film (A) was formed by heating at 300 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose.
[0096]
Table 1 shows the film thickness of the obtained titanium oxide semiconductor film (A) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Spectral sensitizing dye adsorption
As a spectral sensitizing dye, cis- (SCN^-) -Bis (2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium (II)^-FourA mol / liter ethanol solution was prepared. This spectral sensitizing dye solution was applied onto the titanium oxide semiconductor film (A) using an rpm 100 spinner and dried. This coating and drying process was performed five times. The adsorption amount of the spectral sensitizing dye of the obtained titanium oxide semiconductor film was 1 cm of the specific surface area of the titanium oxide film (A).²The amount of adsorption per unit is shown in Table 1. In addition, the weight increment of the semiconductor film after coating and drying was defined as the adsorption amount.
Photoelectric cell creation
First, tetrapropylammonium iodide and iodine are mixed in a solvent in which acetonitrile and ethylene carbonate are mixed at a volume ratio of 1: 4, and the respective concentrations are 0.46 mol / L and 0.06 mol / L. The electrolyte solution was prepared by dissolving so as to be.
[0097]
The glass substrate (A) with an ultraviolet light shielding film / visible light antireflection film prepared as described above is used as one electrode, and fluorine glass-doped tin oxide is formed as the other electrode, and transparent glass carrying platinum thereon The substrates were placed facing each other, the side surfaces were sealed with resin, the electrolyte solution was sealed between the electrodes, and the electrodes were connected with lead wires to produce a photoelectric cell (A).
[0098]
The following evaluation was performed about the obtained photoelectric cell.
Performance evaluation (1)
Photoelectric cell (A) is a solar simulator, 100 W / m²Irradiate light of the intensity, measure Voc (voltage in an open circuit state), Joc (density of current flowing when the circuit is short-circuited), FF (curve factor) and η (conversion efficiency) and tabulate the results Indicated.
[0099]
Performance evaluation (2)
Eye super UV tester (Iwasaki Electric Co., Ltd .: 100 mW / cm) from a distance of 20 cm above the visible light antireflection film surface of the photoelectric cell (A)²) For 10 hours, Voc, Joc, FF and η were measured in the same manner as in the performance evaluation (1), and the results are shown in the table.
[0100]
[Example 2]
Mixing 100 g of titanium oxide / iron oxide composite colloid (catalyst chemical industry Co., Ltd .: sun veil F, average particle size 25 nm, concentration 30 wt%) as ultraviolet shielding particles, and coating solution (B) for forming an ultraviolet shielding film A light electric cell (B) was produced in the same manner as in Example 1 except that it was prepared and used, and performance evaluation (1) and performance evaluation (2) were performed.
[0101]
The results are shown in Table 1.
[0102]
[Example 3]
A coating liquid (C) for forming an ultraviolet shielding film is prepared by mixing 100 g of colloidal cerium oxide (manufactured by Catalyst Kasei Kogyo Co., Ltd .: Sun Veil A, average particle diameter 18 nm, concentration 30% by weight) as ultraviolet shielding particles. A photoelectric cell (C) was prepared in the same manner as in Example 1 except that the performance evaluation (1) and the performance evaluation (2) were performed.
[0103]
The results are shown in Table 1.
[0104]
[Example 4]
Mixing 100 g of titanium oxide / zirconium oxide composite colloid (catalyst chemical industry Co., Ltd .: sun veil Z, average particle diameter 20 nm, concentration 30% by weight) as ultraviolet shielding particles, and coating solution (D) for forming an ultraviolet shielding film A photoelectric cell (D) was produced in the same manner as in Example 1 except that it was prepared and used, and performance evaluation (1) and performance evaluation (2) were performed.
[0105]
The results are shown in Table 1.
[0106]
[Example 5]
Preparation of coating solution for UV shielding film formation
100g of titanium oxide colloid (manufactured by Catalytic Chemical Industry Co., Ltd .: HPW-15R, average particle size 15nm, concentration 30% by weight) is used as UV shielding particles, this is passed through an ultrafiltration membrane, and the dispersion medium is replaced with ethanol. did. 50 g of this ethanol sol (solid content concentration 5% by weight), 3 g of an acrylic resin (manufactured by Hitachi Chemical Co., Ltd .: Hitaloid 1007), and 47 g of a mixed solvent of isopropanol and n-butanol (1/1 by weight) were thoroughly mixed. Thus, an ultraviolet shielding film forming coating solution (E) was prepared.
[0107]
Preparation of coating solution for forming visible light antireflection film
To the dispersion of inorganic compound particles in which the inside of the solid content concentration of 20% by weight, in which the dispersion medium is replaced with ethanol, used in Example 1, is hollow, ethanol is further added to adjust the solid content concentration to 5% by weight. 50 g of this was sampled, and 3 g of acrylic resin (Hitaloid 1007 manufactured by Hitachi Chemical Co., Ltd.) and 47 g of a 1/1 (weight ratio) mixed solvent of isopropanol and n-butanol were sufficiently mixed to form a visible light antireflection film. Coating solution (E) was prepared.
[0108]
Preparation of glass substrate with UV shielding film and visible light antireflection film
While maintaining a transparent polyimide film substrate formed of fluorine-doped tin oxide as an electrode layer at 40 ° C., an ultraviolet shielding film-forming coating solution (E) was applied to the opposite surface of the electrode by a bar coater method (100 rpm by spinner method, The film was applied and dried so that the film thickness of the ultraviolet shielding film was 100 nm under the condition of 90 seconds.
[0109]
Next, on the ultraviolet shielding film, the coating was applied by the bar coater method (spinner method at 100 rpm for 90 seconds) so that the film thickness of the visible light antireflection film was 100 nm and dried at 160 ° C. The glass substrate (E) with an ultraviolet shielding film and a visible light antireflection film was prepared by heat treatment for 30 minutes.
With respect to the glass substrate (E) with an ultraviolet shielding film and a visible light antireflection film, the average reflectance was measured as the luminous reflectance. The results are shown in Table 1.
Formation of semiconductor film
Next, the same coating solution for forming a semiconductor film as used in Example 1 was applied on the electrode surface of the transparent glass substrate with an electrode on which the ultraviolet ray shielding film and the visible light antireflection film were formed, followed by natural drying, followed by low-pressure mercury. 6000mJ / cm using a lamp²The ultraviolet ray was irradiated to decompose the peroxo acid, and the semiconductor film was cured.
[0110]
Further, the titanium oxide semiconductor film (E) was formed by heating at 250 ° C. for 30 minutes to decompose and anneal hydroxypropylcellulose.
Table 1 shows the film thickness of the obtained titanium oxide semiconductor film (E) and the pore volume and average pore diameter determined by the nitrogen adsorption method.
Spectral sensitizing dye adsorption
Next, as in Example 1, spectral sensitizing dye (cis- (SCN^-A ruthenium complex represented by) -bis (2,2′-bipyridyl-4,4′-dicarboxylate) ruthenium (II) was adsorbed. Table 1 shows the amount of adsorption.
Photoelectric cell creation
The polyimide film substrate electrode with the ultraviolet shielding film and the visible light antireflection film prepared as described above is used as one electrode, and fluorine doped tin oxide is formed as the other electrode, and the transparent polyimide film substrate carrying platinum thereon. Are placed opposite to each other, the side surfaces are sealed with resin, the electrolyte solution is sealed between the electrodes, and the electrodes are connected with lead wires to produce a photoelectric cell (E). Similarly, performance evaluation (1) and performance evaluation (2) were performed.
[0111]
The results are shown in Table 1.
[0112]
[Comparative Example 1]
Photoelectric cell creation
In Example 1, a photoelectric cell (F) was prepared in the same manner as in Example 1 except that a transparent glass substrate in which fluorine-doped tin oxide was formed as an electrode without forming an ultraviolet shielding film or a visible light antireflection film was used. Were manufactured, performance evaluation (1) and performance evaluation (2) were performed, and the results are shown in the table.
[0113]
[Comparative Example 2]
Photoelectric cell creation
In Example 5, light was used in the same manner as in Example 5 except that a transparent polyimide film substrate formed with fluorine-doped tin oxide as an electrode without forming an ultraviolet shielding film or a visible light antireflection film was used as one electrode. An electric cell (G) was produced, and performance evaluation (1) and performance evaluation (2) were performed.
[0114]
The results are shown in Table 1.
[0115]
[Table 1]

[Brief description of the drawings]
FIG. 1 shows a schematic cross-sectional view of one embodiment of a photovoltaic cell of the present invention.
[Explanation of symbols]
10 …… Photoelectric cell
11 ... Transparent electrode layer
12 ... Semiconductor film
13 ... Electrode layer with reduction catalytic activity on the surface
14 …… Electrolyte
15 …… Visible light antireflection film
16 …… UV shielding film
P-1, P-2 …… Board

Claims (5)

A substrate (P-1) comprising a metal oxide semiconductor film (2) having an electrode layer (1) on the surface and adsorbing a photosensitizer on the surface of the electrode layer (1);
A substrate (P-2) 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,
At least one of the substrate and the electrode layer has transparency,
In the photoelectric cell in which the electrolyte layer is provided between the metal oxide semiconductor film (2) and the electrode layer (3),
On the outer surface of the substrate (P-1) and / or the substrate (P-2) having at least one of transparency, selected C e, F e, T i , S b, Zr, from the group consisting of Z n one or more metal oxide particles, or, C e, F e, T i, S b, Zr, ultraviolet shielding comprising the composite oxide particles of two or more metals selected from the group consisting of Z n A photoelectric cell characterized in that a film is formed. The ultraviolet light shielding film is formed on the outer surface of the transparent substrate (P-1), the visible light antireflection film is formed on the ultraviolet light shielding film, and the refractive index of the visible light antireflection film is the ultraviolet light shielding film. The photoelectric cell according to claim 1, wherein the photoelectric cell has a refractive index lower than that of the photoelectric cell. The visible light antireflection film is obtained by applying and drying a visible light antireflection film-forming coating solution, followed by heat treatment,
3. The photoelectric cell according to claim 1 , wherein the ultraviolet shielding film is obtained by applying, drying, and heat-treating a coating liquid for forming an ultraviolet shielding film.   The photoelectric cell according to claim 1, wherein a difference in refractive index between the ultraviolet shielding film and the visible light antireflection film is 0.3 or more. The visible light antireflection film is composed of silica and an inorganic oxide other than silica, is composed of porous core particles or cavities, and a silica coating layer having a thickness in the range of 1 to 50 nm, and silica is represented by SiO ₂ . , the molar ratio MO _x / SiO ₂ when the inorganic oxide other than silica, expressed in MO _x is in the range of 0.0001 to 0.3, an average particle diameter as in the range of 5~300nm composite oxide 5. The photoelectric cell according to claim 1, further comprising physical particles.

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