JP5661965B1 - Material for organic solar cell, organic solar cell using the same, and method for producing the material - Google Patents

Abstract

An object of the present invention is to improve the photoelectric conversion efficiency of dye-sensitized and organic semiconductor solar cells. Noble metal nanoparticles-supported metal oxide particles and / or metal particles obtained by depositing noble metal nanoparticles by physical vapor deposition while stirring the metal oxide particles and / or metal particles are used for the organic solar cell. Used as a constituent material. [Selection] Figure 2

Description

  The present invention relates to metal oxide particles and / or metal particles supporting metal nanoparticles suitable for organic solar cells, organic solar cells using the same, and methods for producing the particles.

  In order to build a sustainable society without destroying its material circulation system on a limited earth, clean resources that do not use fossil fuels and uranium, which are exhaustible resources, and do not destroy the resource environment Energy creation is one of the essential issues. In other words, when converting to effective energy used by human beings such as electricity and heat, emissions of harmful substances such as carbon dioxide and nitrogen oxides are small, and fuel such as sunlight, wind power, wave power and geothermal heat is unnecessary. There is a need for renewable energy that is replenished by the inexhaustible natural power.

  In particular, solar power generation that converts sunlight into electrical energy is a representative clean energy that is expected to be put into full-scale practical use as solar cells and secondary batteries are developed. Solar cells convert light energy into electrical energy by a semiconductor, and are roughly classified into inorganic and organic depending on the material of the semiconductor. Further, the inorganic system is classified into a silicon semiconductor system and a compound semiconductor system, and the organic system is classified into a metal oxide semiconductor system (dye sensitized type) and an organic semiconductor system.

  Inorganic systems have the problem of high material cost and difficulty in increasing the area, but since conversion efficiency is high, practical application is steadily progressing. On the other hand, the organic type was expected as a solar cell with low material cost and easy to increase in area, but there was a period when development was stagnant because it was difficult to overcome the photoelectric conversion efficiency.

  However, the following improvements have been reported in organic solar cells. First, the dye-sensitized type, called the Gretzel cell, was developed in 1991, and an organic solar cell using a redox electrolyte solution in which a ruthenium dye was dissolved between a negative electrode of a porous titanium oxide semiconductor and a positive electrode of platinum was developed. As a result, a photoelectric conversion efficiency of 7.9% was achieved (Non-patent Document 1). Furthermore, in 1997, due to the improvement of the ruthenium dye, the photoelectric conversion efficiency equivalent to that of the amorphous silicon semiconductor solar cell reached about 10% (Non-patent Document 2). On the other hand, in the organic semiconductor system, the photoelectric conversion efficiency was improved to 2.8% in 2002 by using a polythiophene polymer thin film as an electron donor and a fullerene derivative thin film as an electron acceptor (Non-patent Document 3). ) Research on this system was activated. Recently, there has been a report of achieving a photoelectric conversion efficiency of 10% by a bulk heterojunction organic solar cell in which an electron donor and an electron acceptor are blended (for example, Non-Patent Document 4).

  Nowadays, organic solar cells have high expectations that they can realize cost reduction and large area that are extremely important for full-scale practical use of solar cells. For the time being, the use of organic solar cells is considered to be a power source for small consumer devices used indoors, such as transparent solar cells and flexible solar cells, but in order to realize the above sustainable society. Needs to be a power source used as a residential power generation system to solve energy problems.

  For this reason, characteristics such as durability and photoelectric conversion efficiency are also focused on further improvement. In particular, with regard to photoelectric conversion efficiency, organic solar cells also achieve photoelectric conversion efficiency equivalent to that of amorphous silicon semiconductors in small-area cells, but about 25% of single crystal silicon semiconductors, polycrystalline silicon semiconductors It has not reached about 20% of the system. Further, in the case of an actual large-area cell, since it is greatly reduced to about 7% in the amorphous silicon semiconductor system and about 14% in the single crystal silicon semiconductor system and the polycrystalline silicon semiconductor system, further improvement is urgently required. .

  In such a situation, many reports on applying surface plasmon resonance (SPR, Surface Plasmon Resonance) of metal nanoparticles to the photoelectric conversion efficiency of solar cells have already been recognized. In a silicon semiconductor solar cell, a metal film in which metal nanoparticles are dispersed in an organic or inorganic material (Patent Document 1) or a metal covered with a transparent resin between a silicon semiconductor layer and a transparent electrode Those that form nanoparticles (Patent Document 2) have been reported. In a dye-sensitized solar cell, a silver nanoparticle is dispersed in an electrolyte (Patent Document 3), and a metal nanoparticle or a chemically modified metal nanoparticle is supported on the surface of a porous titanium oxide film forming a photoelectrode ( Patent Documents 4 and 5), a negative electrode in which a regular laminated structure of metal nanoparticles and titanium oxide nanoparticles is formed from a colloid solution (Patent Document 6), and the like are disclosed. Moreover, it is disclosed that the formation of metal nanoparticles is effective for the counter electrode of the transparent electrode even in the organic semiconductor system (Patent Document 7).

  However, in the application of SPR to such organic solar cells, although the effect of metal nanoparticles on the improvement of photoelectric conversion efficiency is recognized, it surpasses the photoelectric conversion efficiency reached by the various silicon semiconductor solar cells described above. It has not been done. The cause is considered to be due to the fact that conventional metal nanoparticles for inducing SPR use a colloidal solution that is deposited and generated by a liquid phase method, that is, reduction of a noble metal solution. That is, it is difficult to control the particle size of the metal nanoparticles produced by the liquid phase method, and the metal nanoparticles are immersed in and adhered to the electrode substrate from the colloidal solution. This is presumed to be due to a lack of adhesion to the electrode substrate (Patent Documents 4, 5, and 6). On the other hand, although a method of directly forming metal nanoparticles on the electrode substrate using a sputtering method is also conceivable, the metal domain at the initial stage of sputtering is a metal nanoparticle layer, not a spherical nanoparticle layer, The surface area is small (Patent Document 7).

Japanese Patent Application Laid-Open No. 2011-040645 JP 2012-169380 A JP-A-9-259943 JP 2001-035551 A JP 2007-265694 A JP 2007-335222 A JP 2009-246025 A JP2012-057198A International Publication No. 2012/150804

B. O'Regan and M.M. Graetzel, Nature, 353, 737 (1991). M.M. K. Nazeeruddin, P.M. Pechy and M.M. Graetzel, Chem. Commum. , 1705 (1997). P. Schilinsky, C.I. Waldauf, and C.I. J. et al. Brabec, Appl. Phys. Lett. 81, 3885 (2002). Kenichi Sasaki, “Study on Optimization of Bulk Heterotype Device Structure of Organic Thin Film Solar Cell”, Kobe University Doctoral Dissertation (January 2013). JPO Standard Technology Collection, “Outline of dye-sensitized solar cells”, published on March 26, 2004. (Germany) Industrial Property Information and Training Hall, “2005 Patent Distribution Support Chart Nanoparticle Manufacturing Technology”, March 2006. Yasunori Taga, “Research on Thin Film Process Technology”, Integrated Engineering, Vol. 22, 53-64 (2010). W. Ensinger et al. , Surface and Coatings Technology, vol. 163-164, 30 January, 281-285 (2003).

  This invention provides the metal oxide particle and / or metal particle which carry | supported the metal nanoparticle which SPR acts effectively for the purpose of the photoelectric conversion efficiency improvement of an organic type solar cell. Furthermore, the present invention provides an organic solar cell using the material. In addition, an object of the present invention is to provide a method for producing a material suitable for expressing the characteristics of the material. In particular, metal oxide particles carrying metal nanoparticles are suitable for electrode materials for dye-sensitized solar cells.

  When the present inventors perform PVD of metal while stirring metal oxide particles and / or metal particles that are base materials (base materials) of physical vapor deposition (PVD), the metal oxide particles and / or metal It was found that metal nanoparticles were deposited on the particles, and the metal oxide and / or metal particles supported by the metal nanoparticles expressed SPR most effectively, and the present invention was completed. That is, the present invention provides metal oxide particles and / or metal particles carrying metal nanoparticles as a constituent material of an organic solar cell, and also provides an organic solar cell using the same. In addition, the above-described method for producing a material suitable for expressing the characteristics of the material is provided.

More specifically, the present invention is, in PVD chamber, the evaporation source provided thereon, stirred tank for introducing base material in which the evaporation source evaporating material provided in the lower is deposited, in that 撹拌槽撹 agitator, for provided evaporation material is uniformly deposited on the base material at least placed, the metal oxide particles and / or metallic particles with a particle size 1~200nm put into 撹拌層as a base material , Produced by depositing metal nanoparticles having a particle diameter of 1 to 10 nm on the surface of the metal oxide particles and / or metal particles while stirring at least one kind of metal as an evaporation source. Metal nanoparticle-supported metal oxide particles and / or metal particles suitable for a constituent material of an organic solar cell. Moreover, it is an organic solar cell characterized by using it as a constituent material. In addition, the above-described method for producing a material suitable for expressing the characteristics of the material is provided.

  As the metal nanoparticles to be PVD, it is possible to use at least one metal selected from gold, silver, platinum, platinum alloy, palladium, palladium alloy, titanium, and titanium alloy. It is effective for SPR that promotes light absorption of solar cells.

  However, the base material differs depending on the type of organic solar cell. When used as an electrode material of a dye-sensitized solar cell, it is preferable to use metal oxide particles as the base material of the present invention. The metal nanoparticle-supported metal oxide particles are used as a photoelectrode of a dye-sensitized solar cell. It is a suitable electrode material. Specifically, a metal oxide porous film is formed on a transparent substrate on which a transparent conductive film is formed and a counter electrode obtained by coating platinum or a carbonaceous material on the transparent substrate on which the transparent conductive film is formed. Dye-sensitized solar cell in which a photoelectrode carrying a dye such as ruthenium complex is opposed to the surface of a porous material film via a redox electrolyte, and voltage is generated between these electrodes by light absorption Is the most effective material for the metal oxide porous membrane. In this case, as the metal oxide, titanium oxide particles are preferable, and anatase type titanium oxide particles are more preferable. And such a metal nanoparticle carrying | support metal oxide particle is disperse | distributed in an organic or inorganic material, and it forms and uses it on the said transparent conductive film.

  On the other hand, in the case of an organic semiconductor solar cell, there is no limitation on the material on which the metal nanoparticles are supported. This is because in the organic semiconductor solar cell, the electron donor absorbs light, is excited, and undergoes photoelectric conversion by transferring electrons from the electron donor to the electron acceptor. For this reason, it is necessary to devise such that all light is absorbed as much as possible, and it is effective to provide a metal oxide particle and / or metal particle layer carrying the metal nanoparticles of the present invention on the electrode. is there. Moreover, you may provide these in any of the incident surface of sunlight, and the electrode of the opposite surface. Of course, when used for the electrode on the incident surface, the particle diameter is limited to a value that maintains sufficient transparency.

  Furthermore, the metal oxide and / or metal particles carrying the metal nanoparticles of the present invention may be dispersed in an electrolyte of a dye-sensitized solar cell or a semiconductor layer of an organic semiconductor solar cell. The metal oxide and / or metal particles on which such metal nanoparticles are supported exhibit SPR more effectively than the metal nanoparticles alone, and the photoelectric conversion efficiency is improved. (Patent Document 3). In this case, the material of the base material is not particularly limited, but is preferably metal oxide particles or metal particles.

  As described above, the base material of the present invention has a direct function of increasing the photoelectric conversion efficiency of the organic solar cell, but is indispensable as a place for depositing uniform metal nanoparticles by the PVD method. Therefore, it is required to have a shape that is a stable material and can always create a new surface.

  The metal nanoparticles for inducing SPR of the present invention are directly formed on the metal oxide particles and / or metal particle surfaces by the PVD method, whereas the vapor phase method using the chemical vapor deposition (CVD) method, the colloid solution system It is necessary to disperse and adsorb the single metal nanoparticles generated from the liquid phase method using a solid phase method such as pulverization with metal oxide particles. Therefore, the metal nanoparticles of the present invention have high purity, uniform and small particle size, and in addition, the metal nanoparticles are directly deposited on the metal oxide particles and / or the metal particle surface. Adhesive strength with metal oxide particles and / or metal particles is strong, and the number of metal nanoparticles can be controlled (Non-Patent Document 6). Based on the characteristics of the present invention, there is an effect exceeding the SPR in the conventional organic solar cell, and the photoelectric conversion efficiency can be improved.

  In a dye-sensitized solar cell, a counter electrode obtained by coating platinum or a carbonaceous material on a transparent substrate on which a transparent conductive film is formed, and the metal oxide particles supporting metal oxide particles on the transparent substrate on which the transparent conductive film is formed When a photoelectrode carrying a dye such as a ruthenium complex is opposed to the surface of a metal oxide film formed using a redox electrolyte so that a voltage is generated between these electrodes by light absorption, There is an effect that exceeds the SPR of the prior art, and the photoelectric conversion efficiency can be improved. Furthermore, by dispersing the metal oxide particles and / or metal particles carrying the metal nanoparticles of the present invention in the electrolyte, it is possible to produce an SPR effect that is greater than that when a single metal nanoparticle is dispersed.

  In the case of an organic semiconductor solar cell, it is not always necessary to support a metal oxide, but a metal nanoparticle-supported metal oxide particle and / or a layer of metal particles is formed on an electrode or dispersed in a semiconductor layer. Then, the light utilization efficiency is improved by the SPR more than that in the case of using conventional single metal nanoparticles, and the photoelectric conversion efficiency is also improved.

It is a schematic diagram of the PVD apparatus which manufactures the metal oxide particle and / or metal particle which carry | supported the metal nanoparticle. It is a schematic diagram of a cross section of a Gretzel type dye-sensitized solar cell using metal oxide particles carrying metal nanoparticles by the PVD method of the present invention as a photoelectrode constituent material.

  The metal oxide particles and / or metal particles carrying the metal nanoparticles of the present invention can be produced using the general PVD apparatus shown in FIG. However, PVD is performed while stirring the base material so that the metal oxide particles and / or metal particles (base material) supporting the metal nanoparticles always face a new deposition surface with respect to the metal (vapor deposition material). There is a need. The formation mechanism of metal nanoparticles by this method is not clear, but can be considered as follows. As film forming mechanisms such as general vapor deposition and sputtering, Volmer-Weber (VW) growth, Frank-van der Merwe (FM) growth, and Strunki-Krastanov (SK) growth are well known (Non-patent Document 7). It is considered that the film formation mechanism differs depending on various parameters such as surface energy and temperature between the PVD substance and the substrate. However, at the initial stage of film formation, the conditions for VW growth were found, and PVD was performed while stirring the base material. For example, since a new deposition surface is always directed to the vapor deposition material, it is assumed that a three-dimensional sea-island structure, that is, metal nanoparticles are generated one after another. Therefore, it is considered impossible to generate nanoparticles without the creation of the new deposition surface (Patent Document 7).

Specifically, as shown in FIG. 1, the evaporation source provided in an upper portion of the PVD chamber, stirred tank for introducing preform evaporated substance provided to deposit the evaporation source below, in 撹拌槽provided evaporation material is at least placed 撹 agitator for uniformly deposited on the base material, while stirring the particles as the base material, by evaporating a metal evaporation source, the metal nanoparticles on the particle surface It is deposited on. As the PVD method, a vacuum deposition method, an ion beam deposition method, an ion plating method, and various sputtering methods can be used. For example, methods such as Non-Patent Document 9, Patent Documents 8 and 9 are disclosed. . In order to prevent oxidation of the metal nanoparticles, the particles on which the metal nanoparticles thus prepared are supported are preferably stored in a container substituted with an inert gas.

  The metal that is a deposition source and becomes nanoparticles is not particularly limited as long as it is a metal, but at least one selected from gold, silver, platinum, platinum alloys, palladium, palladium alloys, titanium, and titanium alloys. More than seed metals are suitable. This is because, when the SPR is reduced to a nano-order (1/10 or less of the wavelength of light), polarization occurs due to vibration of electrons near the surface of the particle, and the metal material and shape, and the metal nanoparticles exist. This is based on the fact that plasmon having a specific wavelength occurs depending on the medium, etc., so that the absorption of light is increased and the photoelectric conversion efficiency is improved. In particular, the excited plasmon resonance frequency ranges from the visible light to the near-infrared wavelength region. Gold, silver, etc. present in However, when applied to a dye-sensitized solar cell, the electrolyte often uses a corrosive halogen-based redox electrolyte, so platinum, platinum alloy, titanium, and titanium are used depending on the electrolyte. It is preferable to use at least one metal selected from the alloys, and it is preferable that the platinum alloy and the titanium alloy contain 50 mol% or more of both platinum and titanium. Of course, in order to improve the photoelectric conversion efficiency of the dye-sensitized solar cell, not only the improvement of the titanium oxide photoelectrode material of the present invention, but also the substrate, transparent electrode, electrolyte, counter electrode constituting the dye-sensitized solar cell Since new materials have been tried from all points of view, and development of non-corrosive electrolytes is underway, the materials are not limited.

The particle diameter of the metal nanoparticles is preferably 1 to 10 nm. More preferably, it is 3-5 nm. The adhesion amount of the metal nanoparticles to the metal oxide particles is preferably a metal oxide particle 1 cm ³ per 0.00001~0.5cm ^3. Furthermore, it is more preferable that the adhesion amount is 0.0001 to 0.1 cm ³ . The particle size and deposition amount (number of particles) can be easily controlled by PVD conditions, the base material 撹拌conditions. It goes without saying that the metal nanoparticles in the above region are effective in improving the photoelectric conversion efficiency of SPR, but the cause of this is not clear, but the laminated structure of the nanoparticles deposited on the particle surface, metal It is related to the interaction between the nanoparticles and the metal oxide particles or metal particles, which are the base material, and it is assumed that this produces an effect that has not been achieved in the past.

  On the other hand, metal oxide particles and metal particles are preferably used as the base material on which the metal nanoparticles are deposited, and there is no particular limitation.

  In particular, metal oxide particles are preferable as a base material for a dye-sensitized solar cell, and titanium oxide, zinc oxide, stannic oxide, tungsten trioxide, niobium oxide, strontium titanate, or a composite system thereof is used. be able to. However, titanium oxide, particularly anatase type titanium oxide, is preferred over rutile type. Further, those not treated with a surface treatment agent such as silicon or stearic acid are preferred. The particle diameter is preferably 1 to 200 nm, more preferably 5 to 100 nm, and still more preferably 15 to 50 nm. When the particle diameter is smaller than 1 nm, it is difficult to generate and attach metal nanoparticles. On the other hand, when the particle diameter is 200 nm or more, the light transmittance is deteriorated, and the light cannot sufficiently act on the pigment and the metal nanoparticles. As such a titanium oxide suitable for the present invention, those used as a catalyst are commercially available, such as ST series and MC series made by Ishihara Sangyo, titanium oxide for catalyst made by Sakai Chemical Industry, AMT series made by Teika, and CAI Kasei. It can be selected from Nano Tech, PC series made by Titanium Industry, DN series made by Furukawa Machine Metal, P series made by Nippon Aerosil. However, when dispersed in the electrolyte of a dye-sensitized solar cell, metal particles may be used, and the particle diameter is the same as that of the metal oxide.

  On the other hand, in the case of an organic semiconductor solar cell, there is no restriction on the material used for the base material, but gold, silver, etc., in which the plasmon resonance frequency induced by light exists in the wavelength of visible light to near infrared light region. preferable. The particle diameter is preferably 1 to 200 nm, more preferably 5 to 100 nm, and still more preferably 15 to 50 nm.

  Subsequently, the metal nanoparticle-supported metal oxide particles will be described more specifically using an example in which the metal nanoparticle-supported metal oxide particles are applied to an electrode material of a dye-sensitized solar cell. However, the technical idea of the present invention is not limited thereto. Rather, it is as described in the means for solving the problems and the effects of the invention.

  A dye-sensitized solar cell using the metal nanoparticle-supported metal oxide particles as a photoelectrode material is produced as follows. First, a photoelectrode including the metal nanoparticle-supported metal oxide particles is obtained by using a paste in which metal nanoparticle-supported metal oxide is dispersed in a surfactant or binder resin solution, an ITO film made of indium oxide and tin oxide, or an oxide. It can be produced by coating and drying on a transparent substrate such as a glass or synthetic resin provided with a transparent electrode such as an FTO film in which tin is doped with fluorine, and then immersing it in a dye solution to adsorb the dye. As a method for applying the paste, a screen printing method, a spin coating method, and other general application methods are properly used depending on the concentration and viscosity of the paste.

  The surfactant used in the paste may be any of ionic, nonionic, and cationic, but as the binder resin, a water-soluble resin having high surface active ability is considered in consideration of dispersibility. preferable. Examples of the water-soluble resin include polyamic acid, polyvinyl alcohol, (meth) acrylic acid copolymer, polyalkylene oxide, polyvinyl pyrrolidone, polyacrylamide, polyvinyl acetal, hydroxyethyl cellulose, and hydroxypropyl cellulose, and are not particularly limited. When the transparent substrate is glass, the binder resin is decomposed at several hundred degrees after drying. Therefore, a water-soluble resin of a cellulose derivative excellent in thermal decomposability is preferable as the binder resin. When the transparent substrate is a synthetic resin, since it cannot be thermally decomposed, a resin that can reduce the binder resin as much as possible and that has excellent dispersibility and high surface activity is preferable.

As the dye, a polypyridylruthenium complex typified by a ruthenium bipyridine complex having a carboxy group is most suitable, but as a central metal, a complex such as iron, copper, or platinum, or a merocyanine-based or cyanine containing no metal is used. Organic pigments such as phthalocyanines, phthalocyanines, porphyrins, azos, coumarins, indolines, and triphenylamines can also be used. In this dye solution, alcohol such as methanol, ethanol, propanol, butanol, or a mixed solvent of these acetonitrile is used as a solvent at a concentration of about 1 to 5 × 10 ⁻⁴ mol / l.

  As the counter electrode of the photoelectrode, a transparent substrate provided with the above transparent electrode and an electrode provided with platinum or a carbonaceous material is suitable, but a conductive polymer film can also be used.

  Between the electrodes, a halogen-based redox electrolyte based on a nitrile organic solvent is sealed and sealed to complete a dye-sensitized organic solar cell. In particular, iodine-based redox electrolytes are most suitable as liquid electrolytes, and reverse current is prevented by dissolving iodine and lithium iodide in nitrile organic solvents such as acetolitol, methoxyacetonitrile, and methoxypropionitrile. 1-propyl-2,3-dimethylimidazolium iodide, which is a room temperature molten salt that lowers the viscosity and smoothes the diffusion of ions, can be added. . Furthermore, a solid electrolyte that can improve the sealing property and long-term stability of the liquid electrolyte can also be used. As the solid electrolyte, a type that adsorbs an organic solvent to a polymer network such as polyalkylene oxide and polyacrylonitrile, a type that uses an ionic liquid such as imidazolium, and a type that uses a hole transport material such as polyacetylene, polypyrrole, and polythiophene Etc.

  Hereinafter, examples of the dye-sensitized solar cell will be described with reference to examples and comparative examples, and a part of the present invention will be described more specifically.

  First, as shown in FIG. 1, an appropriate amount of anatase-type titanium oxide particles having an average particle diameter of about 20 nm is put into a stirring tank 3 provided in the vacuum deposition tank 1. Next, the vapor deposition source 2 is provided with silver pellets for vacuum vapor deposition having an average particle diameter of about 10 mm and a purity of 99.99%.

Next, Ar is introduced into the vacuum deposition tank 1 from the inert gas introduction system 7 while evacuating the vacuum deposition tank so that the degree of vacuum is 1 × 10 ⁴ to 1 torr. When the degree of vacuum is stable, the silver of the evaporation source 2 is evaporated at a rate of 1 to 10 μm / min per unit area on a fixed flat substrate while stirring the propeller 4 of the stirring tank 3 at a rotational speed of 1 to 200 rpm. Then, the shutter 6 is opened, and silver nanoparticles of 1 to 10 nm are formed on the titanium oxide surface. Then, deposited to a silver nano particles of about 0.001 cm ³ per titanium oxide particles 1 cm ^3, closes the shutter 6. The produced silver particle-carrying titanium oxide particles were stored in a container purged with nitrogen.

  An example of a photoelectrode using this silver particle-supported titanium oxide and a dye-sensitized solar cell using the same will be described below.

  As a conductive transparent electrode substrate used as a photoelectrode and its counter electrode, glass for solar cells (manufactured by AGC Fabricec Co., Ltd.) using an FTO film as a transparent conductive film was used.

The silver particle-carrying titanium oxide paste for photoelectrode is put into water containing 10 wt% acetylacetone and 20 wt% ethanol, in which 40 wt% polyethylene glycol 6000 is dissolved so that the silver particle-carrying titanium oxide is 30 wt%, and ultrasonic dispersion is performed. Thus, a paste for photoelectrodes was produced. This was applied to the above equal electrode substrate by a screen printing method to a dry film thickness of about 15 μm, and then fired at 400 ° C. This is a ruthenium complex represented by a ruthenium bipyridine complex having a carboxy group (RuL ₂ (NCS) ₂ , L = 2,2′-bipyridyl-4,4′-dicarboxyacid, manufactured by Aldrich) having a concentration of The ruthenium complex was adsorbed on the titanium oxide part by immersing in a mixed solvent of acetitolyl / ethanol = 1/1 (v / v) dissolved to 2.0 × 10 ⁻⁴ mol / l for 24 hours. Thereafter, it was dried at 80 ° C. for 24 hours to obtain a photoelectrode. On the other hand, the counter electrode was produced by coating platinum on the solar cell glass by a sputtering method.

  The electrolyte injected into the gap between the electrodes is iodine / lithium iodide = 10/3 (w / w) as a redox electrolyte, and 1-propyl-2 as a room temperature molten salt that lowers the viscosity and smoothes the diffusion of ions. , 3-dimethylimidazolium iodide 60 (w), 4-t-butylpyridine 50 (w) which prevents reverse current and increases open electromotive force, dissolved in 3-methoxypropionitrile was used.

  Finally, a polyimide film of 50 μm is sandwiched between the electrode substrates as a spacer, the opening for injecting the electrolyte and the opening for degassing are removed, the periphery is sealed with epoxy resin, the electrolyte is then injected, The deaeration port was sealed to prepare a dye-sensitized solar cell.

Comparative example

  A dye-sensitized solar cell was produced in the same manner as in the example except that the titanium oxide particles of the titanium oxide paste for producing the photoelectrode were anatase-type titanium oxide particles having an average particle diameter of about 20 nm.

As a result of the above, as a result of measuring the current-voltage characteristics by irradiating 1000 W / m ² of pseudo-sunlight with a solar simulator, the example had a photoelectric conversion efficiency about 1.5 times that of the comparative example.

  The metal nanoparticle carrying | support metal oxide particle and / or metal particle of this invention are applicable not only to the electrode of an organic type solar cell but to the component material of various organic solar cells.

  In particular, the metal nanoparticle-supported metal oxide particles of the present invention include a counter electrode obtained by coating platinum or a carbonaceous material on a transparent substrate on which a transparent conductive film is formed, titanium oxide or the like on a transparent substrate on which a transparent conductive film is formed. A metal oxide film is formed, and a photoelectrode carrying a dye such as a ruthenium complex is placed on the surface of the metal oxide film through a redox electrolyte, and voltage is generated between these electrodes by light absorption. In the dye-sensitized solar cell thus made, it is used as a constituent material of the negative electrode metal oxide film. Moreover, the metal nanoparticle carrying | support metal oxide particle and / or metal particle of this invention are utilized also as an electrode material of an organic-semiconductor type solar cell. Furthermore, the metal nanoparticle carrying | support metal oxide particle and / or metal particle of this invention can be utilized as a semiconductor layer of an organic semiconductor type | system | group solar as an electrolyte of a dye-sensitized solar cell. Therefore, the organic solar cell using the metal oxide particle-supported metal oxide particle and / or metal particle of the present invention is excellent in photoelectric conversion efficiency, realizes low cost and large area, and realizes a sustainable society. It is suitable for a possible residential power generation system.

DESCRIPTION OF SYMBOLS 1 Vacuum deposition tank 2 Deposition source 3 Stirring tank 4 Propeller 5 Motor 6 Shutter 7 Inert gas introduction system 8 Vacuum exhaust system 9 Transparent substrate 10 Transparent electrode 11 Platinum or carbonaceous material 12 Oxide particle 13 Metal produced by physical vapor deposition Nanoparticle 14 Dye 15 Redox electrolyte 16 Sun

Claims (3)

In the organic solar cell material capable of improving the photoelectric conversion efficiency by the surface plasmon effect peculiar to the metal nanoparticles , the average of the surface of each metal oxide particle and / or metal particle having an average particle diameter of 15 to 50 nm At least one or more kinds of metal nanoparticles selected from gold, silver, platinum, platinum alloy, palladium, palladium alloy, titanium, and titanium alloy having a particle diameter of 3 to 5 nm are the metal oxide particles and / or organic solar cell material, characterized by being 0.00001～0.5Cm ³ supported per metal particle 1 cm ^3. The organic solar cell which is characterized by using as at least one metal nanoparticle metal oxide is supported particles and / or the constituent material of the organic solar cell of the metal particles of claim 1. In the organic solar cell material that can improve the photoelectric conversion efficiency by the surface plasmon effect peculiar to metal nanoparticles , provided in the physical vapor deposition tank, the evaporation source provided in the upper part of the physical vapor deposition tank, and the lower part of the evaporation source stirring tank for introducing base material was evaporated substance is deposited, said evaporating material provided in 撹拌槽is at least placed 撹 agitator for substantially uniformly deposited on the base material, as the base material The metal oxide particles and / or metal particles having an average particle diameter of 15 to 50 nm are selected from gold, silver, platinum, platinum alloy, palladium, palladium alloy, titanium, and titanium alloy as the evaporation source. using one or more metals, while stirring the metal oxide particles and / or metallic particles, by evaporating the metal, the metal oxide particles and / or metal particles Method for manufacturing an organic solar cell materials, wherein the one one surface to deposit said metal nanoparticles with an average particle diameter 3~5nm of.

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