CN101416345B

CN101416345B - Dye sensitization photoelectric converter

Info

Publication number: CN101416345B
Application number: CN2007800118209A
Authority: CN
Inventors: 米屋丽子; 铃木佑辅; 诸冈正浩
Original assignee: Sony Corp
Current assignee: Sony Corp
Priority date: 2006-02-02
Filing date: 2007-01-31
Publication date: 2012-09-26
Anticipated expiration: 2027-01-31
Also published as: JP2009081141A; CN101416345A; JP4380779B2

Abstract

Provided is a dye sensitization photoelectric converter in which light absorptance and photoelectric conversion efficiency are enhanced. A dye sensitization photoelectric converter (10) comprises a transparent substrate (1) made of glass or the like, a transparent electrode (negative pole) (2) composed of a transparent conductive layer of FTO (fluorine doped tin oxide (IV)SnO2), a semiconductor layer (3) holding a plurality of kinds of photosensitizing dyes, an electrolyte layer (5), a counter electrode (positive pole) (6), a counter substrate (7), and a sealant (not shown). The photosensitizing dyes are composed of a plurality of kinds of dyes having sufficiently different minimum excitation energies, or a plurality of kinds of dyes held on the semiconductor layer (3) with different conformations. The semiconductor layer (3) employs a porous layer obtained by sintering fine particles of titanium oxide TiO2. The electrolyte layer (5) employs an organic electrolyte solution containing an oxidation-reduction species (redox pair) such as I<->/I3<->. The counter electrode (6) composed of a platinum layer (6b) or the like is formed on the counter substrate (7).

Description

Dye sensitization photoelectric converter

Technical field

The present invention relates to and particularly, the present invention relates to have the high absorptivity and the dye sensitization photoelectric converter of photoelectric conversion efficiency as the dye sensitization photoelectric converter of solar cell etc.

Background technology

Utilize the solar cell of sunlight to be regarded as the energy that substitutes fossil fuel, and carried out relative various research.Solar cell is to be used for transform light energy is a kind of photoelectric conversion device of electric energy and utilizes sunlight as the energy.Therefore, solar cell is minimum to the influence of global environment, and expectation is widelyd popularize.

For the principle and the material of solar cell, various researchs have been carried out.Wherein, utilize the solar cell of semiconductor pn knot the most general at present, comprise the solar cell marketization of silicon in a large number as semi-conducting material.Above-mentioned solar cell roughly is divided into silicon metal class solar cell that adopts monocrystalline silicon or polysilicon and the amorphous silicon class solar cell that adopts amorphous silicon.

Transform light energy for the expression sunlight is the photoelectric conversion efficiency of the performance of electric energy, and silicon metal class solar cell is higher than amorphous silicon class solar cell, thereby, at present silicon metal class solar cells that use more.Yet because silicon metal class solar cell needs significant amount of energy and time to be used for crystal growth, thereby production capacity is low, thereby causes expensive.

On the other hand, the characteristic that has of amorphous silicon class solar cell makes it compare with silicon metal class solar cell can in wideer wave-length coverage, to absorb and utilize light and can select various baseplate materials and be easy to realize large tracts of landization.In addition, amorphous silicon class solar cell does not require crystallization, thereby compares and can make with good production capacity and low cost with silicon metal class solar cell.Yet the photoelectric conversion efficiency of amorphous silicon class solar cell is lower than silicon metal class solar cell.

For all these silicon class solar cells, owing to need to make the step and the step that forms the pn knot of high-purity semi-conducting material, thereby have the many problems of manufacturing step; Owing to need the manufacturing step under the vacuum condition, thereby have equipment cost and the high problem of energy cost.

For the solar cell that obtains not have the problems referred to above and can make at lower cost, replace the solar cell of silicon class material to study for a long period of time to using organic material.Yet it is about 1% that great majority use the photoelectric conversion efficiency of the solar cell of organic materials to be low to moderate, thus practicability not also.

Yet; Proposed to utilize the dye sensitization photochemical cell (photoelectric conversion device) of photic electron transfer (photoinduced electron transfer) (to see B.O ' Regan in 1991; M.Graetzel, Nature, 353; P.737-740 (1991) and No. the 2664194th, communique of special permission (p.2-3 and Fig. 1), or the like).Because this photoelectric conversion device has high photoelectric conversion efficiency, do not need large-scale manufacturing system and can use cheap material to make simply with good production capacity, thereby expect it as solar cell of future generation.

Figure 10 is the major part sectional view of the structure of the at present general dye sensitization photoelectric converter 100 of example.This dye sensitization photoelectric converter 100 mainly by transparency carrier 1 for example glass, by transparency conducting layer FTO (fluorine doped tin oxide (IV) SnO for example ₂) transparency electrode (negative pole) 2 that forms, the formations such as semiconductor layer 103, dielectric substrate 5, counter electrode (positive pole) 6, subtend substrate 7 and sealing medium (not shown) that keep a kind of light-sensitive coloring agent.

As semiconductor layer 103, use through sintered titanium dioxide TiO usually ₂The porous layer that particulate obtains.A kind of light-sensitive coloring agent remains on the microparticle surfaces that constitutes this semiconductor layer 103.Dielectric substrate 5 is filled between semiconductor layer 103 and the counter electrode 6, and use comprises for example I of OR material (redox couple) ^-/ I ₃ ^-Organic electrolyte.Counter electrode 6 is made up of platinum layer 6b etc. and is formed on the subtend substrate 7.

Figure 11 is the potential diagram of the operation principle of explanation dye sensitization photoelectric converter 100.When light incident, dye sensitization photoelectric converter 100 conducts serve as anodal with counter electrode 6 and transparency electrode 2 is the battery operated of negative pole.Its principle is described below.(in Figure 11, suppose FTO as transparency electrode 2 materials, following N719 is as light-sensitive coloring agent 104, titanium dioxide TiO ₂As semiconductor layer 103 materials, redox material I ^-/ I ₃ ^-As redox couple.)

When light-sensitive coloring agent 104 absorbed the photon that sees through transparency carrier 1 and transparency electrode 2, the electronics in the light-sensitive coloring agent 104 was energized into excitation state (LUMO) from ground state (HOMO).Combine (electrical coupling) that the excitation state electronics is caused the conduction band of semiconductor layer 103 via the electricity between light-sensitive coloring agent 104 and the semiconductor layer 103, and pass through semiconductor layer 103 arrival transparency electrodes 2.

On the other hand, the light-sensitive coloring agent 104 that loses electronics is accepted in the dielectric substrate 5 for example I of reducing agent according to reactions ^-Electronics, and form the oxidant I for example in the dielectric substrate 5 ₃ ^-(I ₂And I ^-Zygosome):

2I ^-→I ₂+2e ^-

I ₂+I ^-→I ₃ ^-

Formed oxidant arrives counter electrode 6 and accepts the electronics of counter electrode 6 according to reactions (back reaction of above-mentioned reaction) through diffusion, is reduced to initial reducing agent:

I ₃ ^-→I ₂+I ^-

I ₂+2e ^-→2I ^-

The electronics that is delivered to external circuit from transparency electrode 2 is brought into play the electricity effect external circuit, return counter electrode 6 then.Be electric energy with transform light energy by this way, and do not cause both any variations of light-sensitive coloring agent 104 and dielectric substrate 5.

As the light-sensitive coloring agent 104 of dye sensitization photoelectric converter 100, use can absorb the material of the light of contiguous visible region, for example bipyridyl complexes, three pyridine complexs, merocyanine dyes, porphyrin, phthalocyanine etc. usually.

Usually, in order to realize high photoelectric conversion efficiency, think that at present it is favourable using a kind of high-purity dyestuff.This be because, consider when multiple dyestuff mixes on a semiconductor layer 103, electron transfer or the combination again between electronics and the hole between the dyestuff appear; Perhaps caught by different types of dyestuff, thereby reduce, and be that quantum yield obviously reduces and (for example sees K.Hara by absorbing ratio that photon obtains electric current from being excited the electronics that light-sensitive coloring agent 104 arrives transparency electrodes 2 from being excited the electronics that dyestuff transfers to semiconductor layer 103; K.Miyamoto; Y.Abe, M.Yanagida, JournalofPhysical ChemistryB; 109 (50), p.23776-23778 (2005); " Electron Transport inCoumarin-Dye-Sensitized Nanocrystalline TiO ₂Electrodes "; Masatoshi Yanagida, et al., Symposium on Photochemistry (2005), 2P132; " Electron Transport Processin Dye-Sensitized Nanocrystalline Titanium Oxide Electrodes Having RutheniumBipyridine Comlex and Ruthenium Biquinoline Complex Coadsorbed Thereon "; Uchida, http://kuroppe.tagen.tohoku.ac.jp/～dsc/cell.html, FAQ, " Re:TheoreticalEfficiency ofDye-Sensitized Solar Cells "; Or the like).

Dyestuff as independent use; Usually use a kind of bipyridyl complexes---suitable-two (isothiocyanates) two (2; 2 '-bipyridine-4,4 '-dicarboxylic acids) ruthenium (II) two-TBuA salt complex (being commonly referred to " N719 "), it is as the sensitizing dyestuff excellent performance.In addition; Usually use a kind of bipyridyl complexes---suitable-two (isothiocyanatos) two (2,2 '-bipyridine-4,4 '-dicarboxylic acids) rutheniums (II) (being commonly referred to " N3 ") and a kind of three pyridine complexs---(three (isothiocyanatos) (2; 2 ': 6 '; 2 "-three pyridines-4,4 ', 4 "-tricarboxylic acids) ruthenium (II) three-TBuA salt complex (being commonly referred to " Black Dye ").

Especially, when using N3 or Black Dye, use coadsorbent usually.Coadsorbent is to be the molecule that prevents that dye molecule and semiconductor layer 103 bondings from adding, and the representative instance of coadsorbent comprises chenodeoxycholic acid, taurodeoxycholic acid salt and 1-decrylphosphonic acid.The instance of the architectural characteristic of these molecules comprises: these molecules have carboxyl, phosphono etc. as functional group, and said functional group is easy to be adsorbed on the titanium dioxide that constitutes semiconductor layer 103; These molecules form through σ-key, so that these molecules can be between the dye molecule, thereby prevent to interact between the dye molecule.

Usually, work effectively, at first, importantly improve absorptivity, can maximally utilise the light that gets into photoelectric conversion device for making photoelectric conversion device; Secondly, importantly improving the absorbing light power conversion is the conversion efficiency of electric energy.In dye sensitization photoelectric converter, owing to light absorption is realized by light-sensitive coloring agent 104, thereby expectation can obtain maximum absorptivity through selecting have the absorbefacient dyestuff of optimal light as light-sensitive coloring agent 104 to incident light.

Because sunlight comprises from infrared light to ultraviolet wavelength continually varying light; Thereby the time as solar cell; In order to obtain high absorptivity; It is the dyestuff of the light of 300nm-900nm that the light, particularly wavelength of the wide as far as possible scope (comprising Long wavelength region) of absorbing wavelength zone covering are fully selected in expectation.

Yet the state of electronics is that quantum mechanics is confirmed in the light-sensitive coloring agent 104, can not get the energy state except that the intrinsic energy state of material.Therefore; Energy difference between ground state (HOMO) electronics and excitation state (LUMO) electronics; Be that electronics is energized into the required energy of excitation state (band-gap energy) from ground state and confirms also that as the eigenvalue of material the light corresponding to said energy that light-sensitive coloring agent 104 can absorb is limited to the light in the particular wavelength region.In addition, can transit to the conduction band of semiconductor layer 103, require the band-gap energy of dyestuff can be not too small in order to make excitation electron.

Figure 12 (a) shows the absorption spectrum of at present general obtainable four kinds of representative dyestuffs; Figure 12 (b) shows the amplification absorption spectrum of three kinds of little dyestuffs of molar absorption coefficient.Notice that through Figure 12 Black Dye has the absorbing wavelength zone (long wave that comprises contiguous 860nm is terminal) of wide region.But the molar absorption coefficient of Black Dye is on the whole little, particularly has the big inadequately zone of absorptivity in the shortwave side.Although N719 has the molar absorption coefficient that is equal to or greater than Black Dye in the shortwave side, the terminal contiguous 730nm of the long wave side in N719 absorbing wavelength zone can not effectively utilize long wavelength light.[[[4-(2 for 4-for 5-; The 2-diphenylacetylene) phenyl]-1,2,3; 3a; 4,8b-six hydrogen ring penta [b] indoles-7-yls] methylene]-light absorption of 2-(3-ethyl-4-oxygen-2-sulfo--5-thiazolidine subunit)-4-oxo-3-thiazolidine acetate (after this being called " dyestuff B ") has identical with N719 basically wavelength dependency, and its molar absorption coefficient is less than the molar absorption coefficient of N719.[4-[4-(2,2 diphenylacetylene) phenyl]-1,2,3,3a, 4,8b-six hydrogen ring penta [b] indoles-7-yls]-2-acrylic acid (after this being called " dyestuff A ") has big molar absorption coefficient although 2-is cyanic acid-3-, and its absorbing wavelength zone is limited to narrow scope.

As previously mentioned, not existing fully at present, absorbing wavelength is the dyestuff of the sunlight of 300nm-900nm.As under the situation of solar cell, use N719 to obtain best performance at dye sensitization photoelectric converter 100, for example obtain the open circuit voltage of 0.755V and 8.23% photoelectric conversion efficiency as light-sensitive coloring agent 104.When the open circuit voltage of the 0.6V that said result and silicon metal class solar cell reach was compared with 15% photoelectric conversion efficiency, photoelectric conversion efficiency only was the half the more of said silicon metal class solar cell photoelectric conversion efficiency.

The open circuit voltage of considering dye sensitization photoelectric converter 100 is greater than silicon metal class solar cell; Think that the low reason of photoelectric conversion efficiency of DSSC is; The gained photoelectric current is significantly less than silicon metal class solar cell, and main cause is that the absorptivity of light-sensitive coloring agent 104 is big inadequately.Promptly think owing to there is not a dyestuff that can effectively absorb all light of different wave length in the sunlight, thereby the absorptivity of the DSSC that is made up of a kind of dyestuff is big inadequately.

If can not reach enough absorptivities, can consider to use multiple dyestuff that the absorbing wavelength characteristic differs from one another so as light-sensitive coloring agent through a kind of dyestuff.Yet, as previously mentioned, when multiple dyestuff mixes on a semiconductor layer 103 and uses, photoelectric conversion efficiency will be descended.This is because as previously mentioned, from absorbing the ratio that electronics obtains electric current, promptly quantum yield obviously descends through electron transfer between the dyestuff etc.

Make the present invention to afore-mentioned, the purpose of this invention is to provide the absorptivity with raising and the dye sensitization photoelectric converter of photoelectric conversion efficiency.

Summary of the invention

Through extensive and deep research, can improve absorptivity and photoelectric conversion efficiency and accomplish first invention of the present invention thereby inventor of the present invention finds the combination of multiple dyestuff.

Particularly; The present invention relates to first dye sensitization photoelectric converter; Construct this first dye sensitization photoelectric converter; So that remain on the light-sensitive coloring agent absorbing light in the semiconductor layer and make the electronics of the light-sensitive coloring agent that excites through this light absorption output to the outside via said semiconductor layer, it is characterized in that this light-sensitive coloring agent comprise multiple dyestuff and its photoelectric conversion efficiency be at least the photoelectric conversion efficiency of said each dyestuff when using separately add with.

The present invention also finds; In aforementioned dye sensitization photoelectric converter; When the multiple dyestuff of research combination improved the mechanism of photoelectric conversion efficiency, at least a dyestuff in the said multiple dye molecule was under the situation of the functional group that has a plurality of and bonding semiconductor on the same carbon, and this dyestuff suppresses itself and combination of dyes not of the same race; Thereby improved the photoelectric conversion efficiency of said not dyestuff of the same race, thereby accomplish second invention of the present invention.

Particularly; The present invention relates to second dye sensitization photoelectric converter; Construct this second dye sensitization photoelectric converter; So that remain on the light-sensitive coloring agent absorbing light in the semiconductor layer and make the electronics of the light-sensitive coloring agent that excites through this light absorption output to the outside, it is characterized in that via said semiconductor layer:

Multiple molecule remains in the semiconductor layer;

At least a molecule in the said multiple molecule is a light-sensitive coloring agent; With

At least a molecule in the said multiple molecule has functional group that a plurality of and said semiconductor layer combines and the combination that suppresses light-sensitive coloring agent on same carbon, thereby improves the photoelectric conversion efficiency of light-sensitive coloring agent.

Said when beginning like the present invention, the molecule itself that on same carbon, has a plurality of functional groups that combine with semiconductor layer can be a kind of light-sensitive coloring agent, and perhaps differently, said molecule can be the molecule with photoelectric converting function.

First dye sensitization photoelectric converter of the present invention is characterised in that, said light-sensitive coloring agent comprise multiple dyestuff and its photoelectric conversion efficiency be at least the photoelectric conversion efficiency of said each dyestuff when using separately add with.

In order to improve the photoelectric conversion efficiency of dye sensitization photoelectric converter, use a kind of highly purified dyestuff at present usually.Opposite with common practise, the inventor is through experiment confirm, when multiple dyestuff mixes on semiconductor layer, exist photoelectric conversion efficiency be at least adding of the photoelectric conversion efficiency of said each dyestuff when using separately and dye combinations.

In first dye sensitization photoelectric converter of the present invention; Because light-sensitive coloring agent constituting by said multiple dyestuff; Thereby the not mutual quantum yield that reduces of said dyestuff, show photoelectric converting function, and the electric current growing amount increases obviously owing to said multiple dyestuff.Therefore, compare with the situation of said each dyestuff of independent use, can improve absorptivity and reach be at least the photoelectric efficiency of said each dyestuff when using separately add and photoelectric conversion efficiency.

As the device that is intended to improve photoelectric conversion efficiency via the combination of multiple dyestuff; The tandem dye sensitization photoelectric converter has been proposed at present; Wherein made the dye sensitized optoelectronic converting device that in semiconductor layer, keeps each dyestuff separately, and these devices pile up (JP-A-H11-273753 and JP-A-2000-90989 etc.) along the optical transmission direction.In this tandem dye sensitization photoelectric converter; Since incident light at first inject with its near the electrooptical device on the side; In this deepening owing to absorption, reflection or scattering; Inject then with its away from the electrooptical device on the side, thereby have following problems: the dyestuff away from the electrooptical device on incident light one side can not receive incident light in good condition.On the other hand, the advantage of dye sensitization photoelectric converter of the present invention is that all dyestuffs all can receive the same good incident light of state.

Second dye sensitization photoelectric converter of the present invention is characterised in that:

Multiple molecule remains in the semiconductor layer;

At least a molecule in the said multiple molecule has a plurality of functional groups that combine with semiconductor layer and suppresses the combination of light-sensitive coloring agent on same carbon, thereby improves the photoelectric conversion efficiency of light-sensitive coloring agent.

Will be understood that the molecule (after this being called " combining to suppress molecule ") that on same carbon, has a plurality of functional groups combines to present the spatial configuration different with light-sensitive coloring agent and to be adsorbed on the semiconductor layer with semiconductor layer through said functional group.Therefore, even the lip-deep light-sensitive coloring agent of aforementioned molecule adjacent semiconductor layers, it still can exist and not have strong interaction with light-sensitive coloring agent, thereby not suppress the opto-electronic conversion performance of light-sensitive coloring agent.

On the other hand, remain on combination on the semiconductor layer surface and suppress molecule effectively between the light-sensitive coloring agent that remains on the said semiconductor layer similar face and suppress mutually combining of light-sensitive coloring agent, thereby avoid the invalid electron transfer between the light-sensitive coloring agent.Therefore, excitation electron does not ineffectually shift between the light-sensitive coloring agent that has absorbed light and effectively outputs in the semiconductor layer, improves photoelectric conversion efficiency thus.

Therefore; With use coadsorbent for example the existing dye sensitization photoelectric converter of chenodeoxycholic acid compare; In the irradiation simulated solar light time, the responsive photoelectric conversion device of second dyestuff of the present invention can obviously improve IPCE (incident photon-current conversion efficient) and short-circuit current value.

Description of drawings

Fig. 1 is the major part sectional view of example according to the structure of the dye sensitization photoelectric converter of first embodiment of the invention.

Fig. 2 is the potential diagram of explanation according to the working mechanism of the dye sensitization photoelectric converter of first embodiment of the invention.

Fig. 3 shows according to first embodiment of the invention as the Black Dye dyestuff of basic dyestuff with as the structural formula of the dyestuff A that assists dyestuff and the exemplary plot of IPCE spectrum.

Fig. 4 uses the basic dyestuff of Black Dye conduct and uses the IPCE spectrum of dyestuff A as the photoelectric conversion device of auxiliary dyestuff according to first embodiment of the invention.

Fig. 5 example shows the structural formula according to the structure of the N719 of first embodiment of the invention and dyestuff B.

Fig. 6 is the major part sectional view of example according to the structure of the dye sensitization photoelectric converter of second embodiment of the invention.

Fig. 7 example is used N719 and the basic dyestuff of Black Dye conduct and is used the IPCE spectrogram of dyestuff A as the photoelectric conversion device of the embodiment 4 of auxiliary dyestuff.

Fig. 8 example shows the structural formula of the structure of the binding inhibitors (coadsorbent) that uses in the embodiment of the

invention

5,6 and the comparative example 3.

Fig. 9 example is according to the embodiment of the

invention

2,5 and 6 and the IPCE spectrum of the photoelectric conversion device of comparative example 3 and 4 and the enlarged drawing of Long wavelength region thereof.

Figure 10 is the major part sectional view of the structure of the existing general dye sensitization photoelectric converter of example.

Figure 11 is the potential diagram of the working mechanism of the existing general dye sensitization photoelectric converter of explanation.

The present general obtainable wavelength region may of Figure 12 example is in the absorption spectra of four kinds of representative dyestuffs of 300nm-900nm.

Embodiment

In first dye sensitization photoelectric converter of the present invention, expect that the minimum excitation energy of each dyestuff from ground state (HOMO) to excitation state (LUMO) is obviously different each other in the aforementioned multiple dyestuff.In this case, the minimum excitation energy of each dyestuff differs 0.172eV-0.209eV or more in the preferably aforementioned multiple dyestuff.

In addition, expect that a kind of dyestuff and absorption maximum band that aforementioned multiple dyestuff comprises that the absorption maximum band is arranged in 400nm or above wavelength region may are arranged in a kind of dyestuff that is not more than the 400nm wavelength region may.

In addition, expect that aforementioned multiple dyestuff is included in the big dyestuff of visible region quantum yield and the little dyestuff of quantum yield in the visible region.

In addition, expect dyestuff and the little dyestuff of molar absorption coefficient that aforementioned multiple dyestuff comprises that molar absorption coefficient is big.In this case, the molar absorption coefficient of the big dyestuff of expectation molar absorption coefficient be 100,000 or more than, and the molar absorption coefficient of the little dyestuff of molar absorption coefficient is not more than 100,000.

In addition, expect that aforementioned multiple dyestuff remains in the semiconductor layer with the spatial configuration that differs from one another.For example expect that aforementioned multiple dyestuff comprises having inorganic complex dyestuff that causes MLCT (transfer of metal-ligand electric charge) character and the organic molecule dyestuff with CT (electric charge transfer) character in the molecule.Instance with the inorganic complex dyestuff that causes MLCT character comprises polypyridine complex compound for example Black Dye and N719; Instance with organic molecule dyestuff of CT character in the molecule comprises the aromatics conjugated polycyclic molecule of electron donor group and the linear setting of electron acceptor group, for example dyestuff A.

Be meant the molecule that in a part, has electron donor group and electron acceptor group simultaneously like the application's said " organic molecule " with CT character in the molecule.In addition, when semiconductor layer 3 was for example on the surface of titanium dioxide, if the electron acceptor group is arranged on semiconductor layer 3 sides and the electron donor group is arranged on dielectric substrate 5 sides, then this molecule helped electronics and is transferred to semiconductor layer 3 from dyestuff in this Molecular Adsorption.Thereby, expect that this molecule has said structure.This is to be different from charge transfer method and shift direction in the inorganic complex dyestuff that causes MLCT because of charge transfer method and shift direction in the organic molecule dyestuff with CT character.

Instance with the inorganic complex dyestuff that causes MLCT character comprises polypyridine complex compound such as bipyridyl complexes, diquinoline and terpyridyl complex compound, for example Black Dye and N719.Organic molecule dyestuff with CT character be for example have thiophene, if partial structurtes such as tannin, cyanic acid and carbazole as the electron acceptor group and for example have partial structurtes such as naphthoquinones, pyridine radicals and pyrimidine radicals as the organic molecule of electron donor group.Particularly, can enumerate tetrathiafulvalene-four cyano quinone bismethane (TTF-TCNQ) complex compound, asymmetric azo dyes, thiazole azo dye, azulenes etc.; More specifically, can enumerate (referring to Makoto Okawara, Masaru Matsuoka, Tsuneaki Hirashima, Teijiro Kitao, Kinosei Shikiso (Functional Dyes) (Kodansha Ltd.)) such as dyestuff A.

In addition; Expectation is constructed in some way; So that at least a in the aforementioned multiple dyestuff has a plurality of functional groups that combine with semiconductor layer on same carbon; And it combines with the dyestuff not of the same race of the another kind at least in the multiple dyestuff to make this dyestuff inhibition, thereby improve this not photoelectric conversion efficiency of dyestuff of the same race.This dyestuff combines with semiconductor layer through a plurality of functional groups that exist on the aforementioned same carbon and appears and the different spatial configuration of aforementioned dyestuff not of the same race, and aforementioned dyestuff not of the same race only through functional group's absorption, is adsorbed on the semiconductor layer thus.Therefore, even this dyestuff and dyestuff not of the same race are adjacent one another are on semiconductor layer surface, said dyestuff still can coexist and not produce strong interaction and do not suppress the opto-electronic conversion performance each other.On the other hand, this dye molecule effectively between the light-sensitive coloring agent on remaining on the semiconductor layer similar face and suppress with multiple dyestuff in another kind combination of dyes not of the same race at least, prevent the invalid electron transfer between the dyestuff not of the same race thus.Therefore, excitation electron having absorbed between the dyestuff not of the same race of light invalid transfer and effectively having outputed in the semiconductor layer, does not improve the not photoelectric conversion efficiency of dyestuff of the same race thus.

In this case, the aforementioned a plurality of functional groups on same carbon of expecting this dyestuff comprise and the functional group of semiconductor layer insulator and the functional group of closing with the semiconductor layer weak bond.If the aforementioned a plurality of functional groups on same carbon of this dyestuff are the functional group with the semiconductor layer insulator; The spatial configuration degree of freedom that then is adsorbed on this dyestuff on the semiconductor layer is low, makes that being difficult to embody aforementioned a plurality of functional group is present in the effect on the same carbon.On the other hand; Because aforementioned a plurality of functional groups of this dyestuff comprise and the functional group of semiconductor layer insulator and the functional group of closing with the semiconductor layer weak bond, thereby the functional group that weak bond closes brings into play booster action and do not disturb the functional group of insulator and combining of semiconductor layer.Therefore, effectively embody aforementioned a plurality of functional group and be present in the effect on the same carbon.In addition, be transferred to semiconductor layer from insulator functional group, thereby effectively carry out to the electric charge transfer of semiconductor layer owing to absorbed the excitation electron of this dyestuff of light.

For example, expectation is carboxyl-COOH or phosphono-PO (OH) with the functional group of semiconductor layer insulator ₂, and with functional group that the semiconductor layer weak bond closes be cyanic acid-CN, amino-NH ₂, mercapto-SH or thioketones base-CS-.

In second dye sensitization photoelectric converter of the present invention, the aforementioned a plurality of functional groups on same carbon that expectation combines to suppress molecule comprise and the functional group of semiconductor layer insulator and the functional group of closing with the semiconductor layer weak bond.If be the functional group with the semiconductor layer insulator in conjunction with the aforementioned a plurality of functional groups on same carbon that suppress molecule; Then being adsorbed on this combination on the semiconductor layer, to suppress the spatial configuration degree of freedom that molecule appears low, makes to be difficult to embody the effect that has aforementioned a plurality of functional groups.On the other hand; Comprise and the functional group of semiconductor layer insulator and the functional group of closing owing to combine to suppress aforementioned a plurality of functional groups of molecule, thereby weak bond closes functional group's performance booster action and does not disturb combining of insulator functional group and semiconductor layer with the semiconductor layer weak bond.Therefore, effectively embody aforementioned a plurality of functional group and be present in the effect on the same carbon.

After this with reference to accompanying drawing, specify details based on the dye sensitization photoelectric converter of embodiment of the present invention.

First embodiment

Fig. 1 is the major part sectional view of example based on the structure of the dye sensitization photoelectric converter 10 of first embodiment, and said dye sensitization photoelectric converter is mainly corresponding to described first dye sensitization photoelectric converter of claim 1.Dye sensitization photoelectric converter 10 is mainly by transparency carrier 1 glass, transparency conducting layer FTO (fluorine doped tin oxide (IV) SnO for example for example ₂) transparency electrode (negative pole) 2 that constitutes, the formations such as semiconductor layer 3, dielectric substrate 5, counter electrode (positive pole) 6, subtend substrate 7 and unshowned sealing medium that keep multiple light-sensitive coloring agent.

As semiconductor layer 3, use sintered titanium dioxide TiO usually ₂The porous layer that particulate obtains.Multiple light-sensitive coloring agent remains on the microparticle surfaces that constitutes this semiconductor layer 3.Dielectric substrate 5 is filled between semiconductor layer 3 and the counter electrode 6, and use contains for example I of OR material (redox couple) ^-/ I ₃ ^-Deng organic electrolyte.Counter electrode 6 is made up of platinum layer 6b etc. and is formed on the subtend substrate 7.

Dye sensitization photoelectric converter 10 is identical with existing dye sensitization photoelectric converter 100, and different is, and light-sensitive coloring agent comprises the multiple dyestuff that minimum excitation energy differs from one another or comprise with the spatial configuration that differs from one another and remain on the multiple dyestuff in the semiconductor layer 3.

Fig. 2 is the potential diagram of the working mechanism of explanation dye sensitization photoelectric converter 10.During light incident, dye sensitization photoelectric converter 10 is as battery operated, wherein counter electrode 6 as positive pole and transparency electrode 2 as negative pole.Its mechanism is described below.(in Fig. 2, suppose FTO as transparency electrode 2 materials, Black Dye and dyestuff A are as light-sensitive coloring agent 4, titanium dioxide TiO ₂As semiconductor layer 3 materials, and redox material I ^-/ I ₃ ^-As redox couple.)

When light-sensitive coloring agent 4 absorbed the photon that sees through transparency carrier 1, transparency electrode 2 and semiconductor layer 3, the electronics in the light-sensitive coloring agent 4 was energized into excitation state (LUMO) from ground state (HOMO).In this case; In dye sensitization photoelectric converter 10; Because light-sensitive coloring agent 4 comprises multiple dyestuff for example two kinds of

dyestuff

4a and 4b; Thereby compare with the existing dye sensitization photoelectric converter 100 that comprises a kind of dyestuff, can absorb the light in the broad wavelength region may with higher absorptivity.

The excitation state electronics is caused the conduction band of semiconductor layer 3 and pass semiconductor layer 3 arrival transparency electrodes 2 via the electric coupling between light-sensitive coloring agent 4 and the semiconductor layer 3.In this case; Because the multiple dyestuff that the constitutes light-sensitive coloring agent 4 for example multiple dyestuff that differed from one another by minimum excitation energy of Black Dye and dyestuff A is formed perhaps and is made up of the multiple dyestuff that remains in the semiconductor layer 3 with the spatial configuration that differs from one another; Thereby said dyestuff does not reduce quantum yield each other; Show photoelectric converting function, and the electric current growing amount increases obviously owing to said multiple dyestuff.

On the other hand, the light-sensitive coloring agent 4 that loses electronics according to reactions accept reducing agent in the dielectric substrate 5 for example I-electronics and form the oxidant I for example in the dielectric substrate 5 ₃ ^-(I ₂And I ^-Zygosome):

2I ^-→I+2e ^-

I ₂+I ^-→I ₃ ^-

The oxidant that forms arrives counter electrode 6 through diffusion, accepts the electronics of counter electrode 6 and is reduced to initial reducing agent according to reactions (back reaction of previous reaction):

I ₃ ^-→I ₂+I ^-

I ₂+2e ^-→2I ^-

The electronics that outputs to external circuit from transparency electrode 2 is brought into play the electricity effect external circuit, return counter electrode 6 then.Be electric energy with transform light energy by this way, and do not cause both any variations of light-sensitive coloring agent 4 and dielectric substrate 5.

Each dyestuff in the aforementioned multiple dyestuff that constitutes light-sensitive coloring agent 4 does not have particular restriction, as long as have sensibilization.Yet, can be adsorbed on the semiconductor layer 3 in order to make these dyestuffs, need acid functional group, preferably have carboxyl-COOH or phosphono-PO (OH) ₂Dyestuff, especially preferably have the dyestuff of carboxyl.

Through the extensive and deep research to the different dyes combination, inventor of the present invention has found to improve the dye combinations of absorptivity and photoelectric conversion efficiency.The dyestuff that promptly makes up the little but absorbing wavelength wide ranges of molar absorption coefficient is the dyestuff of Black Dye, N719, dyestuff B etc. (after this this dyestuff is called " basic dyestuff ") but absorbing wavelength narrow range big with molar absorption coefficient for example during dyestuff A etc. (after this this dyestuff is called " auxiliary dyestuff ") for example, the photoelectric conversion efficiency raising.

Fig. 3 is that display performance improves the structural formula of each dyestuff in best Black Dye of effect and the dyestuff A combination and the key diagram of IPCE (incident photon-current conversion efficient) spectrum.Fig. 2 and Fig. 3 through shown in previous notice, as the dyestuff A of auxiliary dyestuff the light absorption of the not enough short wavelength regions of basic dyestuff Black Dye absorptivity had booster action.In addition; The absworption peak wavelength of Black Dye is in 400nm or the above wavelength region may; And the long wave side end in its absorbing wavelength zone is near the 860nm; And the absworption peak wavelength of dyestuff A is in the wavelength region may that is not more than 400nm, and the long wave side end in its absorbing wavelength zone is near the 480nm.Thereby the band-gap energy that proves said two kinds of dyestuffs is obviously different.Think different with at present known instance, the undiminished reason of photoelectric conversion efficiency was when Black Dye and dyestuff A mixed on semiconductor layer 3, and the band-gap energy of said two kinds of dyestuffs is obviously different, thereby was difficult to realize the electron transfer between the dyestuff.

The potential diagram of Fig. 2 shows the mechanism of the photoelectric conversion efficiency raising of dyestuff A in the system that light-sensitive coloring agent is made up of Black Dye and dyestuff A.As previously mentioned, when each dyestuff absorbed a photon, the electronics in the dyestuff was energized into excitation state (LUMO) from ground state (HOMO).In said system, there are two kinds of paths that the excitation state electronics of dyestuff A caused semiconductor layer 3 conduction bands.Promptly there is the directapath 11 that the excitation state electronics of dyestuff A is directly caused semiconductor layer 3 conduction bands, and the excitation state electronics of dyestuff A is at first caused the low-lying level excitation state of Black Dye and causes the indirect path 12 of semiconductor layer 3 conduction bands subsequently from the excitation state of Black Dye.Exist at the same time in the system of Black Dye, the photoelectric conversion efficiency of dyestuff A is owing to the contribution of said indirect path 12 improves.

Fig. 4 shows and uses the basic dyestuff of Black Dye conduct and use the IPCE spectrogram of dyestuff A as the dye sensitization photoelectric converter 10 of auxiliary dyestuff.In Fig. 4, the IPCE spectrum when also having added said each dyestuff of independent use.As previously mentioned, although as the Black Dye of basic dyestuff can be in wide wave-length coverage absorbing light, in short wavelength regions, still have the big inadequately zone of absorptivity.In said short wavelength regions, has the effect that fill-in light absorbs at the big auxiliary dyestuff of this zone absorptivity.Be that dyestuff A is as playing a role at the big light-sensitive coloring agent of this short wavelength regions absorptivity.

Yet described in an embodiment with reference to figure 9 as subsequently, in the system of Black Dye and dyestuff A coexistence, even at the not light absorbing Long wavelength region of dyestuff A, photoelectric conversion efficiency also is improved.Can only be interpreted as that this is because the existence of dyestuff A makes Black Dye improve in the photoelectric conversion efficiency of Long wavelength region.Usually; The effect of this raising photoelectric conversion efficiency is presented as and combines to suppress effect; Be that effect that binding inhibitors is between the light-sensitive coloring agent to be produced has suppressed mutually combining and avoided the invalid transfer of electronics between light-sensitive coloring agent between the light-sensitive coloring agent; Thereby excitation electron is effectively outputed to the semiconductor layer 3 from the light-sensitive coloring agent that has absorbed light, and do not cause the invalid transfer between the dyestuff.Being dyestuff A plays a role as well behaved binding inhibitors at itself not light absorbing Long wavelength region.

Explain in the process of this reason that the inventor finds, because dyestuff A has the structure of carboxyl and cyanic acid and same bond with carbon, thereby dyestuff A can play a role as well behaved binding inhibitors.Being dyestuff A combines with semiconductor layer 3 with cyanic acid and appears and only be adsorbed on the different spatial configuration of Black Dye on the semiconductor layer 3 through carboxyl through being present in carboxyl on the same carbon.Therefore, even dyestuff A and Black Dye are adjacent one another are on semiconductor layer 3 surfaces, said dyestuff still can coexist and not produce strong interaction and do not suppress the opto-electronic conversion performance each other.On the other hand, dyestuff A is between the Black Dye that remains on semiconductor layer 3 similar face effectively and suppresses the combination of Black Dye, thereby avoids the invalid electron transfer between the Black Dye.Therefore, the excitation electron that has absorbed the Black Dye of light also outputs in the semiconductor 3 less than invalid transfer between Black Dye effectively, thereby improves the photoelectric conversion efficiency of Black Dye.

In this case, effectively and expectation be that a plurality of functional groups on same carbon of dyestuff A comprise and the carboxyl of semiconductor layer 3 insulator and the cyanic acid that closes with semiconductor layer 3 weak bonds.If a plurality of functional groups on same carbon of dyestuff A are the functional group with semiconductor layer 3 insulator, the spatial configuration degree of freedom that then is adsorbed on this dyestuff on the semiconductor layer 3 is low, is present in the effect on the same carbon thereby be difficult to show a plurality of functional groups.On the other hand, in dyestuff A, bring into play booster action and do not disturb the carboxyl of insulator and combining of semiconductor layer 3 with the cyanic acid that semiconductor layer 3 weak bonds close.Therefore, effectively show a plurality of functional groups and be present in the effect on the same carbon.In addition, output to semiconductor layer 3 from the carboxyl of insulator, thereby shift to the electric charge of semiconductor layer 3 and effectively to carry out owing to absorbed the excitation electron of the dyestuff A of light.

Fig. 5 shows the structural formula of N719 and dyestuff B.Notice through Figure 12, be similar to BlackDye, comprise short wavelength regions that absorptivity is big inadequately separately and this regional light absorption is had booster action as the dyestuff A of auxiliary dyestuff as the N719 of basic dyestuff and dyestuff B.In addition, N719 and dyestuff B absworption peak wavelength separately is in 400nm or the above wavelength region may and the long wave side end in this absorbing wavelength zone is in and fact proved that said two kinds of dyestuffs are obviously different with the band-gap energy of dyestuff A near the 750nm.Therefore, think to be difficult to realize the transfer of electronics to dyestuff A, even and said two kinds of dyestuffs on semiconductor layer 3, mix, do not reduce photoelectric conversion efficiency yet.

The instance of the basic dyestuff of molar absorption coefficient little (for example being not more than 100,000) but absorbing wavelength wide ranges comprises: xanthene class dyestuff, for example rose-red and erythrosine; Cyanine class dyestuff, for example merocyanine, quinone cyanine and koha; Basic-dyeable fibre, for example phenosafraine, cabriblue, 6-MPR and methylene blue; And azo dyes, phthalocyanine-like compound, coumarin kind compound, bipyridyl complexes, terpyridyl complex compound, two quinoline complexes, anthraquinone dyes and polycyclic quinone dyestuff.Wherein, the ion that comprises the metallic element that is selected from ruthenium Ru, osmium Os, iridium Ir, platinum Pt, cobalt Co, iron Fe and copper Cu has high quantum yield as central metallic ions and pyridine ring or imidazole ring as the complex compound of ligand, preferably as light-sensitive coloring agent.Especially, preferably use N719 or Black Dye.

The instance of the auxiliary dyestuff of molar absorption coefficient big (for example 100,000 or more than) but absorbing wavelength narrow range comprises: eosin W or W S; Derivatives of porphyrin, for example chlorophyll, zinc protoporphyrin and magnesium porphyrin; Rhodamine B.Especially, preferred coloring agent A.

Yet, should not think that light-sensitive coloring agent only limits to this, can use molar absorption coefficient to drop on any dyestuff in the said scope.In addition, should not think that this system only limits to two kinds of dyestuffs, can mix two or more dyestuffs and needn't consider molar absorption coefficient.

The method that light-sensitive coloring agent is remained on the semiconductor layer 3 does not have particular restriction.The expectation light-sensitive coloring agent is dissolved in the suitable solvent (for example alcohol, nitrile, nitromethane, halogenated hydrocarbons, ether, methyl-sulfoxide, acid amides, N-methyl pyrrolidone, 1; 3-dimethyl-imidazolinone, 3-Jia oxazolin ketone, ester, carbonic ester, ketone, hydrocarbon, water; Or the like); Semiconductor layer 3 is immersed in this dye solution, perhaps this dye solution is coated on the semiconductor layer 3, thereby light-sensitive coloring agent is adsorbed on the semiconductor layer 3.In addition, in order to reduce mutually combining between the dyestuff, can deoxycholic aicd etc. be added in this dye solution.

In order to remove unnecessary absorbing dye, after absorbing dye, amine capable of using is handled semiconductor layer 3 surfaces.The instance of amine comprises pyridine, 4-tert .-butylpyridine and polyvinyl pyridine.When amine is liquid, but former state is used or it is dissolved in back use in the organic solvent.

For the parts beyond the light-sensitive coloring agent 4, can adopt with existing dye sensitization photoelectric converter 100 grades in the identical parts of parts, the details of said parts is below described.

Transparency carrier 1 is not had particular restriction,, and can use various baseplate materials as long as its quality and shape make light be easy to therefrom see through.Especially, the baseplate material that preferably visible light is had high permeability.In addition, preferably have the material of high barrier property to stop the water to get into electrooptical device from the outside and gas and to have good solvent resistance and weatherability.The instantiation of said material comprises: transparent inorganic substrate, for example quartz and glass; Transparent plastic substrate, for example PETG, PEN, Merlon, polystyrene, polyethylene, polypropylene, polyphenylene sulfide, polyvinylidene fluoride, acetylcellulose, bromo phenoxy group, aromatic polyamides, polyimides, polystyrene, polyene propyl ester, polysulfones and polyolefin.Thickness to transparency carrier 1 does not have particular restriction, and can when considering light transmittance and intercepting electrooptical device inside and outside performance, suitably select.

Transparency electrode (transparency conducting layer) 2 is formed on the surface of said transparency carrier 1 as electronics output electrode (negative pole).Preferably transparency conducting layer 2 has alap impedance, and particularly, impedance preferably is not more than 500 Ω/cm ², more preferably no more than 100 Ω/cm ²Material as forming transparency conducting layer 2 can use known material.The instantiation of said material comprises indium tin composite oxides (ITO), fluorine doped tin oxide (IV) SnO ₂(FTO), tin oxide (IV) SnO ₂, zinc oxide (II) ZnO and indium zinc composite oxide (IZO).In addition, the material that forms transparency conducting layer 2 is not limited to these materials, and can use wherein the combination of two kinds or more kinds of materials.Transparency conducting layer 2 is through formation such as sputtering methods.

In addition, for the impedance that reduces the electronics outgoing route and improve current collecting efficiency, patternable also forms the high metal wiring of conductance.Although the metal wiring material is not had particular restriction, expectation metal material itself has high corrosion resistance and non-oxidizability and low leakage current.In addition, through protective layer being provided separately even can using the low material of corrosion resistance.In addition, in order to reduce undercurrent, can various sulls barrier layer be provided to metal wiring from substrate.

As semiconductor layer 3, use the porous layer that obtains through the sintered semiconductor particulate usually.As semi-conducting material,, also can use the material of compound semiconductor materials or perovskite structure etc. except being the element semiconductor material of representative with silicon.These semi-conducting materials are preferably the n type, semiconductor material, and wherein conduction band electron becomes charge carrier generation anode current under optical excitation.Particularly, can enumerate titanium dioxide TiO ₂, zinc oxide ZnO, tungsten oxide WO ₃, niobium oxide Nb ₂O ₅,, strontium titanates SrTiO ₃With tin oxide SnO ₂, preferred especially anatase titanium dioxide TiO ₂In addition, the kind of semi-conducting material is not limited thereto, and can use or use wherein two kinds or more kinds of mixture or compounds separately.In addition, semiconductive particles can be various forms as required, for example granular, tubulose and bar-shaped.

Manufacturing approach to semiconductor layer 3 does not have particular restriction.Consider physical property, convenience, manufacturing cost etc.; Preferred wet type manufacturing approach; And preferred following method: with the powder of semiconductive particles or colloidal sol be dispersed in solvent for example in the water with preparation pasty state dispersion, then this pasty state dispersion coating or printing are formed with on the transparency carrier 1 of transparency conducting layer 2 above that.Coating process or printing process are not had particular restriction, can carry out according to known method.For example, can adopt infusion process, gunite, coiling rod method, spin-coating method, rolling method, knife coating and intaglio plate formula rubbing method etc. as coating process; And can adopt toppan printing, hectographic printing method, woodburytype, intaglio ink method, adherography (rubber stamp printing method) and silk screen print method etc. as the wet type print process.

The crystal formation of titanium dioxide is preferably the good Detitanium-ore-type of photocatalytic activity.As anatase titanium dioxide, can use the product that is purchased of Powdered, colloidal sol shape or pulpous state, perhaps can form the titanium dioxide alkoxide with through known method for example Hydrolyze method obtain required particle diameter.When use is purchased powder, preferably eliminate the secondary agglomeration of particle, during preparation pasty state dispersion, preferably use mortar, ball milling etc. that particle is pulverized.At this moment, reunite once more, can acetylacetone,2,4-pentanedione, hydrochloric acid, nitric acid, surfactant, chelating agent etc. be added in the said pasty state dispersion in order to prevent the particle of eliminating secondary agglomeration.In addition, in order to improve the viscosity of said pasty state dispersion, can for example polymer class thickener such as PEO and polyvinyl alcohol or cellulose thickener add in the said pasty state dispersion with various thickeners.

Although the granularity to semiconductive particles does not have particular restriction, be preferably 1-200nm for the particle mean size of primary particle, be preferably 5-100nm especially.In addition, but assorted size greater than the particle of semiconductive particles, thereby scatter incident light and improve quantum yield.The average-size of the particle that mixes separately in this case, is preferably 20-500nm.

In order to make semiconductor layer 3 can adsorb a large amount of light-sensitive coloring agents 4, it is long-pending that semiconductor layer 3 preferably has big real surface, the long-pending microparticle surfaces that comprises in the face of the inner hole of porous layer of said real surface.Therefore, be formed under the state on the transparency electrode 2 at semiconductor 3, long-pending at least 10 times of being preferably semiconductor layer 3 exterior surface area (projected area) of real surface, and more preferably at least 100 times.Although this ratio does not have the upper limit, be generally about 1,000 times.

Usually, along with the increase of semiconductor layer 3 thickness and the contained semiconductive particles number of unit projected area, real surface is long-pending to be increased, and the retainable amount of dye of unit projected area increases.Thereby it is big that absorptivity becomes.On the other hand, when the thickness of semiconductor layer 3 increased, the diffusion length that is transferred to the electronics arrival transparency electrode 2 of semiconductor layer 3 from light-sensitive coloring agent 4 increased.Thereby it is big that the electron loss that causes owing to charge recombination in the semiconductor layer 3 becomes.Thereby semiconductor layer 3 has preferred thickness.This preferred thickness is generally 0.1-100 μ m, more preferably 1-50 μ m, especially preferably 3-30 μ m.

Also particulate is electrically connected to each other for semiconductive particles is coated with or is printed on the transparency electrode 2,, preferably calcines this semiconductor layer 3 with the mechanical strength of raising semiconductor layer 3 and the adhesiveness of raising and transparency electrode 2.Although the scope to calcining heat does not have particular restriction, when temperature is too high, the possibility that exists transparency electrode 2 resistance to increase, the possibility that also exists transparency electrode 2 to melt in addition.Thereby calcining heat is preferably 40 ℃-700 ℃, more preferably 40 ℃-650 ℃ usually.In addition, although calcination time is not had particular restriction, be generally about 10 minutes-10 hours.

After the calcining, for the surface area that improves semiconductive particles and improve the constriction between the semiconductive particles, the titanium dioxide ultramicron colloidal sol that titanium tetrachloride aqueous solution for example capable of using or diameter are not more than 10nm carries out impregnation process.Using plastic base when supporting the transparency carrier 1 of transparency electrode (transparency conducting layer) 2, can use the pasty state dispersion that contains binding agent making semiconductor layer 3 on the transparency conducting layer 2 and this semiconductor layer 3 is being crimped on the transparency conducting layer 2 through hot pressing.

Can use gel or solid-state electrolytic solution or electrolyte as dielectric substrate 5.As electrolyte, enumerate the solution that comprises oxidation-reduction system (redox couple).Particularly, use iodine I ₂Combination or bromine Br with metal or organic iodide salt ₂Combination with metal or organic bromide salt.The cation that constitutes slaine comprises lithium ion Li ⁺, sodium ion Na ⁺, potassium ion K ⁺, cesium ion Cs ⁺, magnesium ion Mg ²⁺, calcium ion Ca ²⁺Deng, as the cation that constitutes organic salt, quaternary ammonium ion for example tetraalkyl ammonium ion, pyridinium ion and imidazol ion is favourable.But, should not be construed as the present invention and only limit to this.These materials can use separately or can use wherein two kinds or more kinds of mixtures.

In addition, metal complex for example the combination or the like that for example gathers combination, viologen dyestuff, quinhydrones and the quinone of vulcanized sodium (polysodium sulfide) and alkyl hydrosulfide and alkyl disulfide of combination, the sulfur-containing compound of combination and the ferrocene and the ferricinum ion of ferrocyanic acid salt and ferricyanate can be used as electrolyte.

Wherein, iodine I ₂With lithium iodide LiI, sodium iodide NaI or quaternary ammonium compound for example the electrolyte processed of the combination of iodate imidazoles be particularly advantageous.The concentration of electrolytic salt is preferably 0.05M-10M with respect to solvent, more preferably 0.2M-3M.Iodine I ₂Or bromine Br ₂Concentration be preferably 0.0005M-1M, 0.001-0.5M more preferably.In addition, in order to improve open circuit voltage or short circuit current, can add various additives for example 4-tert .-butylpyridine and benzimidazole.

The instance that constitutes the solvent of electrolyte comprises water, alcohol, ether, ester, carbonic ester, lactone, carboxylate, phosphotriester, heterocyclic compound, nitrile, ketone, acid amides, nitromethane, halogenated hydrocarbons, methyl-sulfoxide, sulfolane, N-methyl pyrrolidone, 1,3-dimethyl-imidazolinone, 3-Jia oxazolin ketone and hydrocarbon.Yet, should not be construed as the present invention and only limit to this.These solvents can use or use wherein two kinds or more kinds of mixtures separately.The ionic liquid at room temperature that in addition, can use tetraalkyl class, pyridines or imidazoles quaternary ammonium salt is as solvent.

Leak or constitute the solvent evaporates of electrolyte in order to reduce electrolyte from dye sensitization photoelectric converter 10 liquid, also can use dissolving such as gelling agent, polymer, cross-linking monomer or be dispersed in the mixture that obtains in the electrolyte components as gel-like electrolyte.For the ratio of gum material and electrolyte components, when the amount of electrolyte components was big, although ionic conductivity is high, mechanical strength reduced.On the contrary, when the amount of electrolyte components was too small, although mechanical strength is big, ionic conductivity reduced.Therefore, the amount of electrolyte components is preferably the 50wt%-99wt% of gel-like electrolyte, more preferably 80wt%-97wt%.In addition, can obtain all solid state photoactivate photoelectric conversion device through with electrolyte and plasticizer and mixed with polymers and volatilize subsequently to remove plasticizer.

As counter electrode 6 materials, can use any material, as long as be conductive materials.In the time of on conductive layer is formed in the face of the insulating material side of dielectric substrate 5, this also can use.Yet the material that preferably uses electrochemical stability is as counter electrode 6 materials.Particularly, platinum, gold, carbon, conducting polymer etc. are used in expectation.

In addition,, preferably, form counter electrode 6 in some way, micro-structural is formed on the surface of the counter electrode 6 that contacts dielectric substrate 5, thereby it is long-pending to increase real surface in order to improve catalytic action to reduction reaction in the counter electrode 6.For example, when relating to platinum, preferably counter electrode 6 forms with the form of platinum black, and when relating to carbon, preferably counter electrode 6 forms with the form of porous carbon.Platinum black can be through formation such as anodic oxidation platinum method, chloroplatinic acid processing, and porous carbon can pass through sintered carbon particulate, calcining organic polymer or other method and form.

Owing to do not require subtend substrate 7 printing opacities, thereby can use jealous glass plate, plastic plate, ceramic wafer and metallic plate as subtend substrate 7 materials.In addition, through form on the transparent counter electrode transparency conducting layer and by the metal with high oxidation reducing catalysis action for example platinum on this transparency conducting layer, forms the transparent subtend substrate that distribution perhaps utilizes the chloroplatinic acid treatment surface to obtain, can be used as subtend substrate 7.

Manufacturing approach to dye sensitization photoelectric converter 10 does not have particular restriction.When electrolyte is liquid; Perhaps introducing liquid electrolyte with in dye sensitization photoelectric converter 10 inside during with its gelatine; Inject the electrolyte into dye sensitization photoelectric converter 10 method be preferred, seal and be provided with inlet around this dye sensitization photoelectric converter 10 in advance.

In order to seal dye sensitization photoelectric converter 10, make semiconductor layer 3 and counter electrode 6 against each other and suitable gap is set so that they are not in contact with one another, and in the zone that does not form semiconductor layer 3 stacking substrates 1 and subtend substrate 7.Although the gap length between semiconductor layer 3 and the counter electrode 6 does not have particular restriction, this gap length is generally 1-100 μ m, more preferably 1-50 μ m.When this clearance distance was excessive, conductance reduced, and photoelectric current reduces.

Although the sealing medium material is not had particular restriction, preferably has the material of light resistance, insulating properties or water proofing property.Can use various welding methods and epoxy resin, ultraviolet curable resin, acrylic resin, polyisobutene resin, EVA (ethylene-vinyl acetate), ionomer resin, pottery, various thermal viscosity resins etc.In addition, the position that inlet is set there is not particular restriction, only otherwise be arranged on semiconductor layer 3 and get final product in the face of on the counter electrode 6 of semiconductor layer 3.

Although the method for implanting to electrolyte does not have particular restriction, several solution are poured on the inlet and through capillarity they are introduced is a kind of simple method.In addition, implant operation can under reduced pressure carry out as required or in heating, carry out.After solution is injected fully, remove the solution that remains in the inlet, and inlet is sealed.Although the sealing method is not had particular restriction yet, sealing medium adhesion glass plate capable of using if desired or plastic base are realized sealing.

In addition, be that the polymer solution that will comprise this electrolyte and plasticizer through The tape casting or other method is coated on the semiconductor layer 3 in the time of will using electrolyte or all solid state electrolyte of gelatines such as polymer at electrolyte.Subsequently, make the plasticizer volatilization, it is removed fully, utilize sealing medium to seal then in the above described manner.Preferably use vacuum seal device etc. under inert atmosphere or under the decompression, to carry out sealing.After sealing, also can heat as required and pressurize, so that the electrolyte of dielectric substrate 5 is penetrated in the semiconductor layer 3 fully.

Dye sensitization photoelectric converter based on first embodiment of the invention can be processed different shape according to its application, and its shape is not had particular restriction.

Second embodiment

Fig. 6 is the major part sectional view of example based on the structure of the dye sensitization photoelectric converter 20 of second embodiment, and this dye sensitization photoelectric converter 20 is mainly corresponding to described second dye sensitization photoelectric converter of claim 14.This dye sensitization photoelectric converter 20 mainly by transparency carrier 1 for example glass, by transparency conducting layer FTO (fluorine doped tin oxide (IV)) SnO for example ₂The formations such as semiconductor layer 23, dielectric substrate 5, counter electrode (positive pole) 6, subtend substrate 7 and unshowned sealing matrix of the transparency electrode (negative pole) 2 that constitutes, maintenance light-sensitive coloring agent and binding inhibitors.

Be similar to the semiconductor layer 3 of dye sensitization photoelectric converter 10, expectation is used through sintered titanium dioxide TiO ₂The porous layer that particulate obtains is as semiconductor layer 23.Light-sensitive coloring agent and binding inhibitors remain on the surface of the particulate that constitutes this semiconductor layer 23.This dielectric substrate 5 is filled between semiconductor layer 23 and the counter electrode 6, and use comprises for example I of redox material (redox couple) ^-/ I ₃ ^-Deng organic electrolyte.Counter electrode 6 is processed and is formed on the subtend substrate 7 by platinum layer 6b etc.

Dye sensitization photoelectric converter 20 is identical with existing dye sensitization photoelectric converter 100; Different is has a plurality of and functional groups semiconductor layer 23 bondings as the characteristic binding inhibitors of this embodiment on same carbon, and this binding inhibitors is to suppress molecule through the combination that the combination that suppresses light-sensitive coloring agent can improve the photoelectric conversion efficiency of light-sensitive coloring agent.This combination suppresses molecule and can be a kind of light-sensitive coloring agent itself, the perhaps different therewith molecules with photoelectric converting function that can be.

The functional group that expectation combines to suppress molecule comprises and the functional group of semiconductor layer 23 insulator and the functional group of closing with semiconductor layer 23 weak bonds.If be the functional group with semiconductor layer 23 insulator in conjunction with the aforementioned a plurality of functional groups on same carbon that suppress molecule; The spatial configuration degree of freedom that then is adsorbed on the combination inhibition molecule on the semiconductor layer 23 is low, makes to be difficult to embody the effect that a plurality of functional groups exist.On the other hand; Because a plurality of functional groups that combine to suppress molecule comprise and the functional group of semiconductor layer 23 insulator and the functional group of closing with semiconductor layer 23 weak bonds, thereby the functional group that weak bond closes brings into play booster action and do not disturb the functional group of insulator and combining of semiconductor layer 23.Therefore, effectively embody a plurality of functional groups and be present in the effect on the same carbon.For example, expectation is carboxyl-COOH or phosphono-PO (OH) with the functional group of semiconductor layer 23 insulator ₂, and with functional group that semiconductor layer 23 weak bonds close be cyanic acid-CN, amino-NH ₂, mercapto-SH or thioketones base-CS-.

Light-sensitive coloring agent there is not particular restriction, as long as it has sensibilization.Yet, can be adsorbed on the semiconductor layer 23 in order to make light-sensitive coloring agent, need acid functional group, preferably have carboxyl-COOH or phosphono-PO (OH) ₂Dyestuff, especially preferably have the dyestuff of carboxyl.

The instance of light-sensitive coloring agent comprises: xanthene class dyestuff, for example rhodamine B, rose-red, eosin and erythrosine; Cyanine class dyestuff, for example merocyanine, quinone cyanine and koha; Basic-dyeable fibre, for example phenosafraine, cabri blue, 6-MPR and methylene blue; Porphyrin compound, for example chlorophyll, zinc protoporphyrin and magnesium porphyrin; And azo dyes, phthalocyanine-like compound, coumarin kind compound, bipyridyl complexes, anthraquinone dyes and polycyclic quinone dyestuff.Wherein, Comprise pyridine ring or imidazole ring and have high quantum yield as central metal ion metal complex, preferably as light-sensitive coloring agent as ligand and the ion that is selected from the metallic element among ruthenium Ru, osmium Os, iridium Ir, platinum Pt, cobalt Co, iron Fe and the copper Cu.Especially, N719 or Black Dye have wide absorbing wavelength scope and are preferred.Yet light-sensitive coloring agent is not limited thereto and can uses or use wherein two kinds or more kinds of mixtures separately.

Method to keeping light-sensitive coloring agent and binding inhibitors does not have particular restriction.Expectation is dissolved in light-sensitive coloring agent and binding inhibitors in the suitable solvent (for example alcohol, nitrile, nitromethane, halogenated hydrocarbons, ether, methyl-sulfoxide, acid amides, N-methyl pyrrolidone, 1; 3-dimethyl-imidazolinone, 3-Jia oxazolin ketone, ester, carbonic ester, ketone, hydrocarbon, water; Or the like); Semiconductor layer 23 is immersed in this dye solution, perhaps this dye solution is coated on the semiconductor layer 23, thereby light-sensitive coloring agent is adsorbed on the semiconductor layer 23.

In addition, in order to reduce mutually combining between the light-sensitive coloring agent, can coadsorbent be added in the light-sensitive coloring agent solution.As coadsorbent, for example can use chenodeoxycholic acid, taurodeoxycholic acid salt, 1-decrylphosphonic acid etc., use chenodeoxycholic acid usually.The concentration of said coadsorbent is generally 10 μ mole/L-0.5mole/L, is preferably 0.3 μ mole/L-0.2mole/L especially.

After the absorption light-sensitive coloring agent, amine capable of using is handled the surface of semiconductor layer 23.The instance of amine comprises pyridine, 4-tert .-butylpyridine and polyvinyl pyridine.When amine is liquid, but former state is used or it is dissolved in back use in the organic solvent.

For except that light-sensitive coloring agent and the parts the binding inhibitors, can adopt with dye sensitization photoelectric converter 10 in the identical parts of parts.Thereby, omit description to it for avoiding repetition.

Dye sensitization photoelectric converter based on second embodiment of the invention can be processed different shape according to its application, and its shape is not had particular restriction.

Embodiment

Below describe embodiments of the invention, only limit to this but should not be construed as the present invention.In the present embodiment, make dye sensitization photoelectric converter as shown in Figure 1 10 or dye sensitization photoelectric converter 20 as shown in Figure 6, measure for example opto-electronic conversion speed of its performance, and compare with Comparative Examples.

< manufacturing of dye sensitization photoelectric converter >

Embodiment 1

With reference to Recent Advances in Research and Development for Dye-SensitizedSolar Cells (supervised by Hironori Arakawa; 2001; CMC Publishing Co., Ltd.), preparation forms the titanium dioxide TiO of raw material as semiconductor layer 3 ₂The pasty state dispersion.When promptly at first at room temperature stirring different third titanium oxide of 125mL is dropwise added in the aqueous solution of nitric acid of 750mL0.1M lentamente.After dropwise add accomplishing, this mixture transferred in 80 ℃ the constant temperature oven, and continue to stir 8 hours.Thereby obtain muddy translucent sol solution.Allow this sol solution to be cooled to room temperature and also filter via glass filter subsequently, adding solvent subsequently is the solution of 700mL with the preparation volume.The gained sol solution is transferred in the autoclave, carried out hydro-thermal reaction 12 hours in 220 ℃, sonicated one hour is to accomplish dispersion treatment then.Subsequently, use evaporator to concentrate and prepare this solution in 40 ℃, so that TiO ₂Content is 20wt%.To be equivalent to TiO ₂500,000) and be equivalent to TiO the polyethylene glycol of quality 20% (molecular weight: ₂The particle diameter of quality 30% is the Detitanium-ore-type TiO of 200nm ₂Add in this concentrated sol solution, evenly mix this mixture through stirring degasser, thereby obtain the TiO that viscosity increases ₂The pasty state dispersion.

Through knife coating with aforementioned TiO ₂The pasty state dispersion is coated on the FTO layer as transparency electrode (transparency conducting layer) 2, thereby formation is of a size of 5mm * 5mm and thickness is the particulate layer of 200 μ m.Subsequently, the particulate layer was kept 30 minutes down at 500 ℃, thus on the FTO layer sintering TiO ₂Particulate.With 0.1M titanium chloride (IV) TiCl ₄The aqueous solution dropwise is added on sintering TiO ₂On the film, at room temperature keep 15 hours after, clean this TiO ₂Film was also calcined 30 minutes in 500 ℃ once more.Subsequently, use UV (ultraviolet ray) device at TiO ₂Irradiation ultraviolet radiation is handled on the sintered body, with oxidation Decomposition and remove TiO ₂Impurity that contains in the sintered body such as TiO ₂The organic material that catalytic action produced, and improve TiO ₂The activity of sintered body, thus semiconductor layer 3 obtained.

With all being dissolved in the 50mL volume ratio through the 23.8mgN719 of complete purifying and 2.5mg dyestuff A as light-sensitive coloring agent 4 is in the mixed solvent that forms of the mixture of 1/1 the acetonitrile and the tert-butyl alcohol (after this abbreviating " mixed solvent of the acetonitrile and the tert-butyl alcohol " as), thereby makes light-sensitive coloring agent solution.

Then, semiconductor layer 3 was flooded 24 hours in this light-sensitive coloring agent solution in room temperature, thereby light-sensitive coloring agent is remained on TiO ₂On the microparticle surfaces.Then, utilize the acetonitrile solution of 4-tert .-butylpyridine and acetonitrile to clean this semiconductor layer 3 in order, then, in the dark evaporating solvent carries out drying subsequently.

Use the electrode make as follows as counter electrode 6: through sputtering method on the FTO layer in order stack thickness be that the chromium layer and the thickness of 500 dusts is 1; The platinum layer of 000 dust; Isopropyl alcohol (2-propyl alcohol) solution spraying of chloroplatinic acid on it and in 385 ℃ of heating 15 minutes, is pre-formed the inlet of 0.5mm in the wherein said FTO layer.

The semiconductor layer 3 that will pass through above-mentioned processing is oppositely arranged with counter electrode 6, and the ionomer resin film and the ultraviolet curing acrylic resin that utilize 30 μ m are with outside seal.

On the other hand, with 0.030g sodium iodide NaI, 1.0g1-propyl group-2, the iodate of 3-methylimidazole, 0.10g iodine I ₂Be dissolved in the 2.0g methoxy propionitrile with 0.054g4-tert .-butylpyridine (TBP), with preparation electrolyte.

Utilize infusion pump to inject this electrolyte from the inlet of ready-made dye sensitization photoelectric converter 10, the pressure that reduces this conversion equipment is to eliminate its inner bubble.Subsequently, utilize ionomer resin film, acrylic resin and glass substrate sealing inlet, thereby accomplish dye sensitization photoelectric converter 10.

Embodiment 2

With all being dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent 4, thereby make light-sensitive coloring agent solution through the 25.5mg Black Dye and the 3.2mg dyestuff A of complete purifying.Then, semiconductor layer 3 was flooded 72 hours in this light-sensitive coloring agent solution in room temperature, thereby light-sensitive coloring agent is remained on TiO ₂On the microparticle surfaces.In addition, carry out subsequently with embodiment 1 in identical step, thereby make dye sensitization photoelectric converter 10.

Embodiment 3

With all being dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent 4, thereby make light-sensitive coloring agent solution through the 14.8mg dyestuff B and the 2.5mg dyestuff A of complete purifying.In addition, carry out subsequently with embodiment 1 in identical step, thereby make dye sensitization photoelectric converter 10.

Embodiment 4

With all being dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent 4, thereby make light-sensitive coloring agent solution through 8.9mg N719,12.8mg Black Dye and the 1.6mg dyestuff A of complete purifying.

Then, semiconductor layer 3 was flooded 48 hours in this light-sensitive coloring agent solution in room temperature, thereby light-sensitive coloring agent is remained on TiO ₂On the microparticle surfaces.Then, utilize the acetonitrile solution of 4-tert .-butylpyridine and acetonitrile to clean this semiconductor layer 3 in order, then, in the dark evaporating solvent carries out drying subsequently.In addition, carry out subsequently with embodiment 1 in identical step, thereby make dye sensitization photoelectric converter 10.

Comparative example 1

The 29mg N719 that will pass through complete purifying is dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent, thereby makes light-sensitive coloring agent solution.In addition, carry out subsequently with embodiment 1 in identical step, thereby make the dye sensitization photoelectric converter that is similar to dye sensitization photoelectric converter 10.

Comparative example 2

The 18.5mg dyestuff B that will pass through complete purifying is dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent, thereby makes light-sensitive coloring agent solution.In addition, carry out subsequently with embodiment 1 in identical step, thereby make the dye sensitization photoelectric converter that is similar to dye sensitization photoelectric converter 10.

Embodiment 5

The 13.6mg Black Dye that will pass through complete purifying is dissolved in as light-sensitive coloring agent in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol, adds 1.3mg alpha-cyano cinnamic acid then therein as binding inhibitors, thereby makes light-sensitive coloring agent solution.Then, flooding 72 hours in this light-sensitive coloring agent solution in room temperature, thereby light-sensitive coloring agent and binding inhibitors are remained on TiO with semiconductor layer 23 that embodiment 1 identical mode obtains ₂On the microparticle surfaces.Then, utilize the acetonitrile solution of 4-tert .-butylpyridine and acetonitrile to clean this semiconductor layer 23 in order, then, in the dark evaporating solvent carries out drying subsequently.In addition, carry out subsequently with embodiment 1 in identical step, thereby make dye sensitization photoelectric converter 20.

Embodiment 6

The 13.6mg Black Dye that will pass through complete purifying is dissolved in as light-sensitive coloring agent in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol, adds 5.1mg phenylthiohydantoin-tryptophan then therein as binding inhibitors, thereby makes light-sensitive coloring agent solution.In addition, carry out subsequently with embodiment 5 in identical step, thereby make dye sensitization photoelectric converter 20.

Comparative example 3

The 25.5mg Black Dye that will pass through complete purifying is dissolved in the 50mL ethanol as light-sensitive coloring agent, adds the 392.6mg chenodeoxycholic acid then therein as binding inhibitors, thereby makes light-sensitive coloring agent solution.Then, with embodiment 1 in the semiconductor layer 23 that obtains of identical mode flooded 72 hours in this light-sensitive coloring agent solution in room temperature, thereby said light-sensitive coloring agent and binding inhibitors are remained on TiO ₂On the microparticle surfaces.Then, utilize ethanol to clean this semiconductor layer 23, then, in the dark evaporating solvent carries out drying subsequently.In addition, carry out subsequently with embodiment 5 in identical step, thereby make the dye sensitization photoelectric converter that is similar to dye sensitization photoelectric converter 20.

Comparative example 4

The 13.6mg Black Dye that will pass through complete purifying is dissolved in the mixed solvent of the 50mL acetonitrile and the tert-butyl alcohol as light-sensitive coloring agent, thereby makes light-sensitive coloring agent solution.In addition, carry out subsequently with embodiment 5 in identical step, thereby make the dye sensitization photoelectric converter that is similar to dye sensitization photoelectric converter 20.

< performance evaluation of dye sensitization photoelectric converter >

Irradiation simulated solar irradiation (AM1.5,100mW/cm ²), record as above the current-voltage curve of the dye sensitization photoelectric converter of the embodiment 1-6 that makes and comparative example 1-4, therefrom obtain short circuit current, open circuit voltage, fill factor, curve factor and the photoelectric conversion efficiency of said dye sensitization photoelectric converter.Table 1 and 2 is respectively done for oneself and is shown the table of aforementioned measurement result.Fill factor, curve factor is also referred to as form factor and is a kind of parameter that embodies the photoelectric conversion device characteristic.In the current-voltage curve of desirable photoelectric conversion device, keep and the identical fixedly output voltage of open circuit voltage size, reach identical up to output current with the short circuit current size.But because the existence of internal resistance, there are deviation in the shape and the ideal current-voltage curve of the current-voltage curve of actual light electrical switching device.The ratio of the area of the rectangular area that surrounds by the area of actual current-voltage curve and x axle and y axle area surrounded with by ideal current-voltage curve and x axle and y axle is called fill factor, curve factor.Fill factor, curve factor shows with the departure degree of ideal current-voltage curve and when calculating the actual light photoelectric transformation efficiency, uses.In addition, in table, Black Dye is abbreviated as " BD " and phenylthiohydantoin-tryptophan is abbreviated as " P-tryptophan ".

Table 1

	Light-sensitive coloring agent	Open circuit voltage (V)	Short-circuit current density (mA/cm ²)	Fill factor, curve factor (%)	Photoelectric conversion efficiency (%)
						Embodiment 1	N719+ dyestuff A	0.776	15.69	71.5	8.71
Embodiment 2	BD+ dyestuff A	0.702	21.22	62.9	10.00
						Embodiment 3	Dyestuff B+ dyestuff A	0.672	13.96	67.1	6.30
Embodiment 4	N719+BD+ dyestuff A	0.729	21.93	66.2	10.58
						Comparative example 1	N719	0.760	15.02	71.8	8.19
Comparative example 2	Dyestuff B	0.680	1346	64.8	5.93

Table 2

	Light-sensitive coloring agent	Open circuit voltage (V)	Short-circuit current density (mA/cm ²)	Fill factor, curve factor (%)	Photoelectric conversion efficiency (%)
						Embodiment 5	BD+ alpha-cyano cinnamic acid	0.701	15.79	68.1	7.54
Embodiment 6	The BD+P-tryptophan	0.700	16.22	67.2	7.63
						Embodiment 2	BD+ dyestuff A	0.702	21.22	62.9	10.00
Comparative example 3	The BD+ chenodeoxycholic acid	0.697	15.14	70.2	7.41
						Comparative example 4	BD	0.735	13.83	68.4	6.95

Can know that by table 1 in the combination of N719, Black Dye or dyestuff B and dyestuff A, photoelectric conversion efficiency improves.Although all reasons of this raising also do not obtain explaining, in the first embodiment main cause are illustrated.Fig. 7 shows and uses N719 and the basic dyestuff of Black Dye conduct and use the IPCE spectrum of dyestuff A as the photoelectric conversion device of the embodiment 4 of auxiliary dyestuff.

Fig. 8

show embodiment

5 and 6 and comparative example 3 in the structural formula of the binding inhibitors (coadsorbent) that uses.Alpha-cyano cinnamic acid and phenylthiohydantoin-tryptophan have and functional group's carboxyl of semiconductor layer insulator and functional group's cyanic acid or the amino that closes with the semiconductor layer weak bond on the carbon separately endways.As shown in Figure 3, dyestuff A also has and functional group's carboxyl of semiconductor layer insulator and the functional group's cyanic acid that closes with the semiconductor layer weak bond on the carbon endways.Can know by table 2;

Embodiment

5,6 compares with comparative example 4 (not using binding inhibitors (coadsorbent)) with comparative example 3 (using binding inhibitors (coadsorbent)---the chenodeoxycholic acid that does not have said structure) with 2 photoelectric conversion device 20 and 10 (wherein binding inhibitors remains on respectively on the

semiconductor layer

23 and 3 with light-sensitive coloring agent) has good short-circuit current density and photoelectric conversion efficiency, has proved superiority of the present invention.

Fig. 9 shows (a)

embodiment

2,5 and 6 and the IPCE spectrum of the photoelectric conversion device of Comparative Examples 3 and 4; (b) enlarged drawing of the Long wavelength region of said IPCE spectrum.Can know by Fig. 9 (a), because this effect in short wavelength regions performance light-sensitive coloring agent of dyestuff A, thereby in the short wavelength regions of 350nm-600nm, the IPCE spectrum of the photoelectric conversion device of the embodiment 2 of use dyestuff A is superior to the IPCE spectrum of other photoelectric conversion device.This is the short-circuit current density and the excellent reason of photoelectric conversion efficiency of table 2 illustrated embodiment 2.

Yet, notice when scrutinizing, even do not show in the Long wavelength region of photoelectric converting function that the IPCE of the photoelectric conversion device of embodiment 2 spectrum also is superior to the IPCE spectrum of other photoelectric conversion device at dyestuff A.This is because dyestuff A has improved the photoelectric conversion efficiency of the BlackDye of the basic dyestuff of conduct at Long wavelength region as binding inhibitors.

Although invention has been described for reference implementation scheme and embodiment, should not be construed as the present invention and only limit to this.Obviously, can be as suitable change in the scope that does not depart from the present invention's design.

Industrial applicibility

Dye sensitization photoelectric converter of the present invention is applied to solar cell etc., realizes the high-performance and the low cost of solar cell and helps its popularization.

Claims

1. dye sensitization photoelectric converter; Construct said dye sensitization photoelectric converter; So that remain on the light-sensitive coloring agent absorbing light in the semiconductor layer and make the electronics of the said light-sensitive coloring agent that excites through said light absorption output to the outside, it is characterized in that via said semiconductor layer:

Said light-sensitive coloring agent comprise multiple dyestuff and its photoelectric conversion efficiency be at least the photoelectric conversion efficiency of said each dyestuff when using separately add with; Wherein said multiple dyestuff remains in the said semiconductor layer with the spatial configuration that differs from one another, and wherein said multiple dyestuff comprises having inorganic complex dyestuff that causes the metal-ligand charge transfer property and the organic molecule dyestuff with intramolecular charge transfer character.

2. the dye sensitization photoelectric converter of claim 1; Wherein said each dyestuff of multiple dyestuff has the minimum excitation energy from ground state (HOMO) to excitation state (LUMO), and the minimum excitation energy of each dyestuff differs 0.172-0.209eV or more in the said multiple dyestuff.

3. the dye sensitization photoelectric converter of claim 1, wherein said multiple dyestuff comprise that a kind of dyestuff and absorption maximum band that the absorption maximum band is arranged in 400nm or above wavelength region may are arranged in a kind of dyestuff less than the 400nm wavelength region may.

4. the dye sensitization photoelectric converter of claim 1, wherein said inorganic complex dyestuff comprises the polypyridine complex compound.

5. the dye sensitization photoelectric converter of claim 4, wherein said polypyridine complex compound is bipyridyl complexes, diquinoline and terpyridyl complex compound.

6. the dye sensitization photoelectric converter of claim 1, wherein said organic molecule dyestuff be have be selected from thiophene, if tannin, cyanic acid and carbazole partial structurtes as the electron acceptor group and have and be selected from naphthoquinones, pyridine radicals and pyrimidine radicals partial structurtes organic molecule as the electron donor group.

7. the dye sensitization photoelectric converter of claim 1, wherein said organic molecule dyestuff is tetrathiafulvalene-four cyano quinone bismethane complex compound, asymmetric azo dyes, thiazole azo dye, azulenes.

8. the dye sensitization photoelectric converter of claim 1; Wherein said multiple dyestuff comprises dyestuff and the little dyestuff of molar absorption coefficient that molar absorption coefficient is big; The molar absorption coefficient of the dyestuff that said molar absorption coefficient is big is 100; 000 or more than, and the molar absorption coefficient of the little dyestuff of said molar absorption coefficient is less than 100,000.

9. the dye sensitization photoelectric converter of claim 1; Wherein said to have the inorganic complex dyestuff that causes the metal-ligand charge transfer property be the polypyridine complex compound, and to have the organic molecule dyestuff that intramolecular charge shifts character be the aromatics conjugated polycyclic molecule of electron donor group and electron acceptor group line-shape arrangement.

10. the dye sensitization photoelectric converter of claim 1; At least a dyestuff in the wherein said multiple dyestuff has the functional group of a plurality of and said semiconductor layer bonding on same carbon; And said dyestuff suppresses at least a combination of dyes not of the same race in itself and the said multiple dyestuff, thereby improves the photoelectric conversion efficiency of said not dyestuff of the same race.

11. the dye sensitization photoelectric converter of claim 10; Wherein said a plurality of functional group comprises and the functional group of said semiconductor layer insulator and the functional group of closing with said semiconductor layer weak bond that the said and functional group semiconductor layer insulator is carboxyl-COOH or phosphono-PO (OH) ₂, and functional group said and that the semiconductor layer weak bond closes is cyanic acid-CN, amino-NH ₂, mercapto-SH or thioketones base-CS-.