CN101840795B - Flexible dye-sensitized solar cell - Google Patents

Abstract

A flexible dye-sensitized solar cell, comprising a flexible conductive substrate, a dye-sensitized nanoporous semiconductor film, an electrolyte and a flexible counter electrode, the flexible conductive substrate is coated with an organic conductive polymer layer on a polymer substrate In the organic conductive polymer film, the thickness of the organic conductive polymer layer is 0.1-3 μm. The conductive substrate of the battery of the present invention has good surface uniformity, good flexibility and good light transmittance, and the battery has good flexibility, can be bent, has no cracks after arbitrary curling, has good photoelectric performance and long service life.

Description

A flexible dye-sensitized solar cell

technical field

The invention relates to a solar cell, in particular to a flexible dye-sensitized solar cell.

Background technique

With its characteristics of no pollution, no transportation, no monopoly, simple maintenance, safe operation and inexhaustibility, solar energy is considered to be the best choice to solve the two major problems of energy depletion and environmental pollution, so countries are actively developing this Green renewable energy. In 1991, the solar cell research group led by Professor Gratzel of the Lausanne Institute of Technology in Switzerland successfully developed the dye-sensitized solar cell (DSSC for short). With the continuous improvement of this kind of solar cell by Gratzel et al., the photoelectric conversion efficiency of DSSC reached 11.9%. Compared with the traditionally used silicon solar cells, this low-cost and environmentally friendly solar cell has the advantages of indoor power generation, large cumulative power generation, low energy consumption, and no pollution in the production process.

DSSC is composed of a conductive substrate, a dye-sensitized nanoporous semiconductor film, an electrolyte, and a counter electrode coated with a catalytic layer. Traditional DSSCs use transparent glass coated with a conductive layer of FTO or ITO metal oxide as the conductive substrate. In recent years, flexible DSSCs prepared with flexible, light-weight polymer substrates or metal foils coated with conductive layers have attracted domestic attention due to their outstanding advantages such as light weight, bendability, low cost, and wide application. It is highly valued by foreign scholars and research institutions.

There are mainly two kinds of flexible conductive substrates used in the preparation of flexible DSSC photoanodes.

One is a high molecular polymer substrate coated with a conductive layer. At present, a layer of inorganic metal oxide ITO (indium tin oxide) conductive layer is commonly used on the high molecular polymer substrate. Disadvantage 1: This layer of ITO The ceramic film is fragile and has poor flexibility, so when the polymer substrate is bent, the ITO conductive film on it is prone to micro cracks, which makes the conductivity of the film worse, and its thermal and chemical stability is also low. It is relatively poor, which will affect the preparation process of the flexible DSSC photoanode and the photoelectric performance and service life of the battery assembled by the flexible DSSC photoanode in the flexible application process. Disadvantage 2: The element indium contained in the ITO conductive film is a rare earth element, and the raw materials are scarce and the cost is high. Disadvantage 3: The preparation of ITO conductive film on polymer substrate requires expensive vacuum magnetron sputtering equipment, and the process is relatively complicated.

Another flexible conductive substrate is metal foil, such as stainless steel or titanium foil with a thickness of 0.05-0.2mm. Although its flexibility and thermal stability are good, its disadvantage is that it is opaque. If the metal foil When it is used to make a photoanode, the light must enter from the opposite electrode side when the battery is in use. In this way, on the one hand, the platinum layer on the surface of the counter electrode absorbs and reflects light; on the other hand, the distance of light passing through the electrolyte is longer when it is incident on the counter electrode than when it is incident from the photoanode, that is, the light reaches the semiconductor thin film electrode. Before that, it is necessary to pass through the electrolyte between the semiconductor film and the counter electrode, and this part of the electrolyte will absorb part of the light again, resulting in a decrease in the short-circuit current.

Contents of the invention

Aiming at the problems and deficiencies in the above-mentioned existing flexible dye-sensitized solar cells, the technical problem to be solved by the present invention is: to provide a flexible dye-sensitized solar cell, the conductive substrate of the cell has good surface uniformity and good flexibility , Good light transmittance, good flexibility of the battery, can be bent, no cracks after arbitrary curling, good photoelectric performance and long service life.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A flexible dye-sensitized solar cell, comprising a flexible conductive substrate, a dye-sensitized nanoporous semiconductor film, an electrolyte and a flexible counter electrode, the flexible conductive substrate is coated with an organic conductive polymer layer on a polymer substrate In the organic conductive polymer film, the thickness of the organic conductive polymer layer is 0.1-3 μm.

The organic conductive polymer in the organic conductive polymer film is any one of polypyrrole, polythiophene and polyaniline.

The sheet resistance of the organic conductive polymer film is 10-400Ω/□, and the transmittance of visible light is greater than 50%.

The nanoporous semiconductor film in the dye-sensitized nanoporous semiconductor film is a film formed by compounding one or more semiconductors of wide bandgap nanocrystals TiO ₂ , SnO ₂ , ZnO, ZrO ₂ , and WO ₃ .

The sensitizing dye in the dye-sensitized nanoporous semiconductor film is any one of N3, N719, Z907, N712, N749, Z907Na, Z910, C101, D102, D149, D205, and C217.

The electrolyte is a liquid electrolyte.

The flexible counter electrode is coated with a layer of platinum or carbon film with a thickness of 4-200 nm on a conductive plastic film with a thickness of 0.05-0.2 mm or a conductive metal foil substrate.

Dye-sensitized solar cells consist of conductive substrates, dye-sensitized nanoporous semiconductor films, electrolytes and electrodes. Traditional dye-sensitized solar cells use transparent glass coated with FTO or ITO metal oxide conductive layers, polymer substrates coated with conductive layers or metal foils as conductive substrates. These conductive substrates have poor flexibility and poor conductivity. Opaque, the battery is prone to tiny cracks when it is bent, poor photoelectric performance, and short service life.

In order to obtain a flexible and bendable conductive substrate, the conductive substrate used in the present invention is an organic conductive polymer film coated with an organic conductive polymer layer on a high molecular polymer substrate. Among them, the polymer base material can be selected from 0.1-0.2mm transparent polyester, polyethylene terephthalate, polyethylene naphthalate, polyimide, polycarbonate, poly Any one of styrene and polypropylene, preferably polyethylene terephthalate PET with low price and excellent performance.

In order to make the surface uniformity of the obtained conductive substrate good and ensure the transparency and photoconductivity of the battery, the present invention coats a layer of organic conductive polymer layer with a thickness of 0.1-3 μm on the high molecular polymer substrate. Transparency and conductivity are two important indicators for evaluating the performance of organic conductive polymer films. When one of the properties is improved, the other will inevitably be reduced. This is because both transparency and conductivity are related to the thickness of the conductive polymer layer. The thinner the conductive polymer layer, the higher the transparency, but the lower the conductivity; on the contrary, the thicker the conductive polymer layer, the lower the transparency, but the higher the conductivity. In addition, the conductive polymer layer is too thin or too thick, will affect Regarding the uniformity of the surface of the conductive substrate, the thickness of the organic conductive polymer layer in the present invention is controlled at 0.1-3 μm in consideration of the above factors. The organic conductive polymer can be selected from any one of polypyrrole, polythiophene, and polyaniline, preferably polythiophene conductive polymer PEDT, such as Bayer's commercial product "Baytron P". Due to the doping of polystyrene sulfonate (PSS), the PEDT polymer is easily dispersed in water and exhibits excellent thermal stability and atmospheric stability, such as Bayer's CLEVIOS PH500, CLEVIOS PH750, and CLEVIOS PH1000 one or more mixtures of . The organic conductive polymer is supplemented with additives to prepare a dispersion liquid with a certain solid content, and any coating process in dip coating, roll coating, blade coating, micro gravure coating, and screen printing is used, preferably blade coating Coated on PET by cloth or screen printing process, it can form a thickness of 0.1-3μm, preferably 0.2-1μm, a sheet resistance of 10-400Ω/□, preferably 10-100Ω/□, and a visible light transmittance greater than 50%. 75%-88% organic conductive polymer films are preferred. The organic conductive polymer film with this performance is used as the flexible conductive substrate of the dye-sensitized solar cell, which solves the poor flexibility of the existing conductive substrate of the battery, which is prone to micro cracks when bent, poor conductivity, opaque, and poor photoelectric performance of the battery. , short service life and other shortcomings.

The specific preparation method of the organic conductive polymer film suitable for the present invention can adopt the Chinese patent application number 200910075550.9 (named a liquid composition based on a polythiophene-based conductive polymer, a conductive polymer film and its use) disclosed method.

In order to improve or ensure the photoelectric performance and service life of the battery, it is necessary to ensure that the battery does not produce cracks when it is bent, because the existence of cracks makes the conductivity of the film worse, and its thermal stability and chemical stability are also relatively poor, so that It will cause the battery to have disadvantages such as poor photoelectric performance and short service life in the flexible application process. In order to obtain a battery with good flexibility, no cracks after random curling, good photoelectric performance and long service life, the present invention coats a nanoporous semiconductor slurry on a flexible conductive substrate to prepare a nanoporous semiconductor film. Good strength and no cracks in bending, this is because the nanoporous semiconductor paste containing organic polymer binders (such as ethyl cellulose, polyethylene glycol) can perfectly match with the same organic polymer conductive polymer layer, so that Because of its better spreadability and better binding force on the organic polymer conductive polymer layer, it solves the problem of poor adhesion, poor uniformity, and bending of the nanoporous semiconductor film prepared on the inorganic metal oxide ITO conductive film. Defects prone to cracks.

In addition to loading sensitizing dyes, the main function of the nanoporous semiconductor film is the collection and conduction of electrons, which must meet at least the following three conditions:

1) It must have a large enough specific surface area to be able to absorb a large amount of dyes;

2) The dye adsorption method of the nanoporous semiconductor film must ensure that electrons are effectively injected into the conduction band of the film;

3) Electrons have a faster transport speed in the film, thereby reducing the recombination of electrons and electrolyte acceptors in the film.

Nanoporous SnO ₂ , ZrO ₂ , and WO ₃ thin films cannot fully meet these three conditions, so their efficiency as photoanodes to make flexible dye-sensitized solar cells is relatively low. The difference between the conduction band potentials of TiO ₂ and ZnO semiconductors is very small, both of which are below the LOMO of the dye, so the photo-excited electrons of the dye can be injected into the conduction band; electrons have greater mobility in TiO ₂ and ZnO semiconductors; The specific surface area of the film formed by _TiO2 or ZnO semiconductor is very large and can absorb more dyes, so the nanoporous semiconductor film of the present invention is preferably a film formed by TiO2 or ZnO semiconductor.

The sensitizing dye suitable for the present invention is any one of N3, N719, Z907, N712, N749, Z907Na, Z910, C101, D102, D149, D205, C217, preferably one of N3, N719 or Z907 dyes kind. Since the above-mentioned wide bandgap semiconductor can only absorb light with a wavelength below 387nm, it cannot absorb the visible light that accounts for most of the sun, and its ability to capture sunlight is very poor. Therefore, in order to improve the light absorption ability of the nanoporous semiconductor film and extend the spectral response of the system to the visible region, the nanoporous semiconductor film must be sensitized.

Sensitizing dyes are currently roughly divided into two categories: pyridine organometallic complexes and organic dyes. Poly(or poly)pyridine nail (Ru) series is currently the most researched and applied photosensitive dye, they have special chemical stability, good redox and excited state reactivity, long excited state lifetime, quantum yield High, good luminescence performance, strong photosensitization for energy and electron transport. Dyes N3, N719, Z907, N712, N749, Z907Na, Z910 and C101 are all carboxylic acid polypyridine nail (Ru) dyes. Among them, the preferred sensitizing dye of the present invention is one of N3, N719 or Z907 dyes, all of which can be selected from the sensitizing dyes provided by Suzhou Zhongsheng Chemical Co., Ltd., and their molecular structures are as follows. They have good adsorption groups (carboxyl groups), which can be well bonded to the surface of nanoporous semiconductors (such as TiO ₂ ), so that the electron injection efficiency is high. The N719 dye molecule replaces two of the 4 carboxyl groups in N3 with -NBu4, so that the N719 dye can be self-assembled and adsorbed on the electrode, and the open circuit voltage is increased by 50-100mV. The Z907 dye molecule contains an amphiphilic group, thereby improving the adsorption capacity of the dye on the surface of nanoporous semiconductor (such as TiO ₂ ) and enhancing the stability of DSSC. N712, Z910 and Z907Na can all be selected from the sensitizing dyes produced by Solaronix Company in Switzerland, N749 can be selected from the sensitizing dyes produced by Wuhan Geao Science and Education Instrument Co., Ltd., and C101 can be selected from the sensitizing dyes produced by Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. dye.

Molecular structure of N3 Molecular structure of N719 Molecular structure of Z907

D102, D149, D205 and C217 all belong to organic dyes, do not contain metal nails (Ru), have the characteristics of low cost and easy synthesis, wherein D102, D149 and D205 all can be selected from the sensitizing dyes produced by Swiss solaronix company, C217 can Selected from sensitizing dyes produced by Changchun Institute of Applied Chemistry, Chinese Academy of Sciences.

As an important part of the dye-sensitized solar cell, the electrolyte acts as a charge exchange medium in the dye-sensitized solar cell, so that each component in the cell returns to its initial state to complete the closed circuit. The electrolyte reduces the dye in the oxidized state at the photoanode, and at the same time itself is reduced by accepting the electrons transported from the counter electrode. According to the state of the electrolyte, the electrolytes used in dye-sensitized solar cells are mainly divided into liquid electrolytes, sol-gel electrolytes, and solid electrolytes.

The electrolyte of the present invention is preferably a liquid electrolyte with the best photoelectric conversion performance, which mainly consists of three parts: redox couple, organic solvent and additives. At present, the most common redox pair used in the electrolyte of dye-sensitized solar cells is the I ₃ ^- /I ^- pair, which has the electrode potential of the pair and the energy level of the nano-semiconductor electrode and the energy of the oxidized state and the reduced state dye. Levels are matched to the merits. Iodine salt cations are also one of the important factors affecting battery efficiency, and Li ⁺ and imidazole cations are commonly used at present. Adding Li ⁺ in the electrolyte solution can greatly improve the transport of electrons in the semiconductor film, thereby increasing the short-circuit current of the solar cell. Imidazolium cations can not only be adsorbed on the surface of nano-semiconductor particles, but also form a stable Helmholz layer in the nano-porous membrane, which hinders the contact of I ₃ ^-ions with the nano-semiconductor membrane, and effectively inhibits the conduction band electrons from interacting with the electrolyte solution. The recombination of I ₃ ^-ions on the surface of nano-semiconductor particles greatly improves the filling factor, output power and photoelectric conversion efficiency of the battery. In the electrolyte, the choice of organic solvent is also very critical. At present, the best performance in the liquid electrolyte is the nitrile material, because of its large dielectric constant, low viscosity, and relatively good stability. The commonly used additive in the electrolyte solution is 4-tert-butylpyridine (TBP), because 4-tert-butylpyridine can coordinate with the incompletely coordinated Ti on the surface of the _TiO2 film through the N on the pyridine ring, hindering the conduction band electrons. The recombination of TiO ₂ film surface with I ₃ ^- in the solution can significantly improve the open circuit voltage, fill factor and photoelectric conversion efficiency of solar cells.

As an important part of the dye-sensitized solar cell, the counter electrode catalyzes the reduction reaction of I ₃ ^- in the electrolyte, so that the charge transfer on the counter electrode/electrolyte interface can be carried out quickly and efficiently. Therefore, the counter electrode must meet the following conditions: 1) Good electrical conductivity; 2) Good catalytic performance for I ₃ ^- ; 3) Good corrosion resistance to electrolyte (I ₃ ^- /I ^- ). The flexible counter electrode of the invention is composed of a flexible conductive substrate and a platinum or carbon thin film with a modified layer on its surface that acts as a catalyzer. Among them, the metal foil is preferably made of titanium, because titanium can resist various strong acids and alkalis (such as nitric acid, etc.), and even aqua regia cannot be corroded. At the same time, titanium reserves are relatively abundant, ranking seventh among metals, especially in my country. A large amount of titanium resources, the cost is relatively low. The flexible counter electrode suitable for the present invention is a platinum or carbon thin film with a thickness of 4-200 nm plated on a conductive plastic film with a thickness of 0.05-0.2 mm or a conductive metal foil substrate.

The preparation method of a flexible dye-sensitized solar cell involved in the present invention is to coat an organic conductive polymer layer with a thickness of 0.1-3 μm on a high-molecular polymer substrate with a thickness of 0.1-0.2 mm, and dry it on the A layer of nanoporous semiconductor film with a thickness of 4-50 μm is printed on it. After low-temperature treatment, the obtained organic conductive polymer film flexible photoanode is dye-sensitized and assembled with a flexible counter electrode, and then the electrolyte is removed from the flexible counter electrode. The reserved small hole is injected into the inside of the battery, and after packaging, a flexible dye-sensitized solar battery based on an organic conductive polymer film is obtained.

Wherein, the low-temperature treatment method of the nanoporous semiconductor thin film is any one of ultraviolet radiation method, hydrothermal method, mechanical compression molding method, and electrophoretic deposition method.

Compared with the prior art, the flexible conductive substrate in the present invention has two advantages: one is that it has the advantages of light transmission, good flexibility, and good thermal stability, and the preparation process is simple, and the roll-to-roll large size of the battery can be realized. Second, the nanoporous semiconductor film prepared by coating the nanoporous semiconductor slurry on it is uniform and compact, has good adhesion, and has no cracks when bent.

Description of drawings

Fig. 1 is a schematic structural diagram of a flexible dye-sensitized solar cell provided by the present invention

Among them: 1. Polymer substrate; 2. Organic conductive polymer layer; 3. Dye-sensitized nanoporous semiconductor film; 4. Electrolyte layer; 5. Flexible counter electrode; 6. Nanoporous semiconductor; 7. Sensitization dye.

Detailed ways

The present invention will be described in detail below in conjunction with specific embodiments and accompanying drawings.

The preparation method: firstly, a layer of organic conductive polymer 2 is coated on the high molecular polymer substrate 1, and the organic conductive polymer thin film flexible substrate is obtained after drying. Then print a layer of nanoporous semiconductor 6 on it, after low-temperature treatment by any method in the ultraviolet radiation method, hydrothermal method, mechanical compression molding method, and electrophoretic deposition method, the flexible photoanode of the organic conductive polymer film obtained Perform dye sensitization and assemble the battery with the flexible counter electrode 5, then inject the electrolyte 4 into the interior of the battery from the small hole reserved for the flexible counter electrode, and after packaging, a flexible dye sensitized battery based on an organic conductive polymer film can be obtained. Solar battery. The working principle of the battery: the sensitizing dye 7 on the dye-sensitized nanoporous semiconductor film 3 transitions from the ground state to the excited state after being irradiated by sunlight, and the dye molecules in the excited state inject electrons into the nanoporous semiconductor 6, and the electrons diffuse to The organic conductive polymer layer 2 flows into the external circuit, and the electrons flow into the flexible counter electrode 5 through the external circuit to generate photocurrent. The dye in the oxidized state is reduced and regenerated by the electrolyte in the reduced state, and the electrolyte in the oxidized state receives electrons after the counter electrode receives electrons. be reduced, thereby completing a whole cycle of photoelectric conversion.

Example 1

Select a PET substrate with a thickness of 175 μm, wash it with detergent and absolute ethanol, and coat a layer of polythiophene conductive layer with a thickness of 1 μm on its surface to obtain a sheet resistance of 15Ω/□ and visible light transmittance 78% organic conductive polymer film. The selected polythiophene conductive polymer is a mixture of CLEVIOS PH500 and CLEVIOS PH1000 produced by Bayer, and its preparation method can adopt the method disclosed in the above-mentioned patent.

The nano titanium dioxide P25 powder that takes 2.4g Degussa production is put into the mortar that fills a certain amount of n-butanol, then add 10g of ethyl cellulose with the same content as 10% n-butanol solution and 5g PEG20000 with a solid content of 20% Methanol solution, mixed evenly and ground for 4h to make TiO ₂ slurry. It was printed on the conductive layer of the organic conductive polymer film, and after natural drying, a _TiO2 film with a thickness of about 12 μm was obtained. Then put it under a 500W ultraviolet lamp and irradiate it for 0.5h to prepare nano-TiO ₂ porous film. Immerse the prepared TiO ₂ porous film in 4×10 ^-5 mol/L N719 dye in absolute ethanol, after absorbing for 24-36 hours, wash it with absolute ethanol, and dry it with cold wind to obtain flexible TiO ₂ Photoanode.

A titanium foil with a thickness of 125 μm was selected, cleaned with detergent and absolute ethanol, and an aqueous solution containing 0.5 g of H ₂ PtCl ₆ , 5 g of (NH ₄ ) ₂ HPO ₄ , and 15 g of Na ₂ HPO ₄ was electrochemically A layer of Pt mirror with a thickness of 50nm is deposited on the surface by electroplating method, and a flexible counter electrode titanium foil/Pt is obtained.

The flexible TiO ₂ photoanode and _the flexible counter electrode titanium foil/Pt were bonded together by heating with sarin film, and then the BMII (1 -Butyl-3-methylimidazolium iodide) and 0.5mol/L TBP acetonitrile electrolyte is injected into the battery from the small hole reserved by the flexible counter electrode titanium foil/Pt, and then the small hole is blocked with epoxy resin Live, that is, flexible dye-sensitized solar cells made of organic conductive polymer films. Under the irradiation of 100Mw/cm ² xenon lamp, the measured short-circuit current of the battery is 2.89mA/cm ² , the open-circuit voltage is 0.62V, the filling factor is 0.54, and the photoelectric conversion efficiency is 0.97%.

Example 2

Select a PET substrate with a thickness of 188 μm, wash it with detergent and absolute ethanol, and coat a layer of polyaniline conductive layer with a thickness of 2 μm on its surface to obtain a sheet resistance of 23Ω/□ and visible light transmittance. 75% organic conductive polymer film, its specific preparation method: polyaniline conductive polymer (Wuhan Yuancheng Nanjian Technology Development Co., Ltd.) is placed in acetonitrile, isopropanol and titanium tetrachloride mixed solution, acetonitrile, isopropanol and The volume ratio of titanium tetrachloride is 1:2:1, electric stirring for 2 hours, ultrasonic dispersion for 20 minutes, polyaniline is fully dispersed in acetonitrile, isopropanol and titanium tetrachloride mixed solvent, wherein, polyaniline and mixed solvent The mass ratio is 1:50, and then the residual oxidant and polymerized monomers in the polyaniline are removed by filtration, and then dried for use. At room temperature, the polyaniline after the purification is added in the ethanol solvent in the ratio of mass ratio 1: 20, then add a certain amount of film-forming resin polyurethane resin (PU628-1 that Taixing City Spinning Auxiliary Factory provides), Ultrasonic dispersion was performed for 20 minutes to make it uniform, thereby obtaining a coating liquid. After the mixed coating solution is filtered with non-woven fabric, it is coated on the cleaned transparent substrate PET by gravure coating, and dried by warm air (135°C) for about 10 minutes to prepare an organic conductive polymer. object film.

Use Zn(Ac) ₂ ·2H ₂ O to prepare 0.2mol·L ^-1 absolute ethanol solution, reflux at 90°C for 4 hours, add LiOH·H ₂ O powder at 0°C to make the concentration 0.3 mol·L ^-1 , stirred at this temperature for 25 minutes to form a colloidal solution of ZnO nanoparticles. Centrifuge in a high-speed centrifuge for 15 minutes, add absolute ethanol to the precipitated ZnO nanoparticles to wash, and then wash with a dilute nitric acid solution with pH=4 to obtain ZnO nanoparticle powder with a particle diameter of 10 nm. Then put it into a mortar containing a certain amount of ethanol, mix and grind evenly, and then magnetically stir for 4 hours to obtain a ZnO slurry. It was printed on the conductive layer of the organic conductive polymer film, and a ZnO film with a thickness of about 12 μm was obtained after natural drying. Then a pressure of 120 MPa is applied to it to prepare a nano ZnO porous film. Immerse the prepared ZnO porous film into 4×10 ^-5 mol/L N749 dye in absolute ethanol, after absorbing for 24-36h, wash it with absolute ethanol, and dry it with cold wind to obtain a flexible ZnO photoanode .

Select a conductive plastic film with a thickness of 125 μm, wash it with detergent and absolute ethanol, and use a glass rod to scrape the conductive carbon paste (CCI-305L type provided by Shenzhen Qiandai Electronic Materials Co., Ltd.) onto the conductive plastic film. Then put it into a drying oven and bake it at 150° C. for 0.5 h to deposit a carbon film with a thickness of 80 nm on its surface to obtain a flexible counter electrode conductive plastic film/graphite.

The flexible TiO ₂ photoanode and the flexible counter electrode conductive plastic film/graphite are bonded together by heating with a sarin film, and then the _DMPII ( 1,2-dimethyl-3-propylimidazolium iodide) and 0.5mol/L TBP acetonitrile electrolyte is injected into the inside of the battery from the small hole reserved by the flexible counter electrode titanium foil/Pt, and then the small hole is used Epoxy plugged, that is, flexible dye-sensitized solar cells made of organic conductive polymer films. Under the irradiation of 100Mw/cm ² xenon lamp, the measured short-circuit current of the battery is 3.26mA/cm ² , the open-circuit voltage is 0.61V, the filling factor is 0.47, and the photoelectric conversion efficiency is 0.93%.

Example 3

Select a PET substrate with a thickness of 125 μm, wash it with detergent and absolute ethanol, and coat a layer of polythiophene conductive layer with a thickness of 0.8 μm on its surface to obtain a sheet resistance of 15Ω/□ and visible light transmission. rate of 83% organic conductive polymer film. The selected polythiophene conductive polymer is a mixture of CLEVIOS PH750 and CLEVIOS PH1000 produced by Bayer, and its preparation method can adopt the method disclosed in the above-mentioned patent.

Weigh 3.6g 1mol/L tetrabutyl titanate n-butanol solution and 0.8g nano titanium dioxide P25 powder produced by Degussa and stir thoroughly for 4h to obtain TiO ₂ colloid. It was printed on the conductive layer of the organic conductive polymer film, and after natural drying, a _TiO2 film with a thickness of about 14 μm was obtained. Then it was boiled in pure water at 100 °C for 4 h to prepare nano- _TiO2 porous film. Immerse the prepared TiO ₂ porous film into 4×10 ^-5 mol/L Z907 dye in absolute ethanol, absorb it for 24-36 hours, rinse it with absolute ethanol, and dry it with cold wind to obtain flexible TiO ₂ Photoanode.

A titanium foil with a thickness of 100 μm was selected, cleaned with detergent and absolute ethanol, and the Pt slurry containing the main components of chloroplatinic acid and terpineol was scraped onto the titanium foil with a glass rod, and then dried naturally. Put it into a muffle furnace and sinter at 450°C for 0.5h to deposit a layer of Pt mirror with a thickness of 50nm on its surface, that is, to prepare a flexible counter electrode titanium foil/Pt.

_The flexible TiO ₂ photoanode and the flexible counter electrode titanium foil/Pt were bonded together by heating with sarin film, and then DMPII (1 , 2-dimethyl-3-propylimidazolium iodine) and 0.5mol/L TBP's 3-methoxypropionitrile electrolyte is injected into the interior of the battery from the small hole reserved by the flexible counter electrode titanium foil/Pt, Then the small hole is blocked with epoxy resin, and the organic conductive polymer film flexible dye-sensitized solar cell is made. Under the irradiation of 100Mw/cm ² xenon lamp, the measured short-circuit current of the battery is 3.82mA/cm ² , the open-circuit voltage is 0.62V, the filling factor is 0.52, and the photoelectric conversion efficiency is 1.23%.

Example 4

Select a PET base material with a thickness of 175 μm, wash it with detergent and absolute ethanol, and coat a conductive layer of polypyrrole with a thickness of 1.5 μm on its surface to obtain a sheet resistance of 25Ω/□ and visible light transmittance. It is a 79% organic conductive polymer film, and its specific preparation method: polypyrrole conductive polymer (Wuhan Shizishan Paint Factory) is placed in a mixed solution of formyl nitrile and ethyl acetate, and the volume ratio of formyl nitrile and ethyl acetate is 1:2, magnetic stirring for 3 hours, ultrasonic dispersion for 15 minutes, to fully disperse polypyrrole in the mixed solvent of formonitrile and ethyl acetate, wherein the mass ratio of polypyrrole to the mixed solvent is 1:75, and then remove the polypyrrole by filtration The remaining oxidants and monomers that are not polymerized in the solution should be dried for later use. At room temperature, the purified polypyrrole was added to the methanol solvent in a mass ratio of 1:20, and then a certain amount of film-forming resin polyester resin (MD-1200 provided by Shanghai Haoyang Industrial Development Co., Ltd.) , ultrasonically dispersed for 30 minutes to make it uniform, thereby obtaining a coating liquid. After the mixed coating solution is filtered with non-woven fabric, it is coated on the cleaned transparent substrate PET by gravure coating, and dried by warm air (120°C) for about 15 minutes to prepare an organic conductive polymer. object film.

Weigh 4.8g of nano-titanium dioxide P25 powder produced by Degussa and put it into a mortar filled with a certain amount of ethanol, mix and grind evenly, then magnetically stir for 4h to obtain TiO ₂ slurry. It was printed on the conductive layer of the organic conductive polymer film, and after natural drying, a _TiO2 film with a thickness of about 12 μm was obtained. Then a pressure of 120MPa is applied to it to prepare nano- _TiO2 porous film. Immerse the prepared TiO ₂ porous film in 4×10 ^-5 mol/L N3 dye dehydrated ethanol, after absorbing for 24-36h, wash it with dehydrated ethanol, and dry it with cold wind to obtain flexible TiO ₂ Photoanode.

Select a conductive plastic film with a thickness of 175 μm, wash it with detergent and absolute ethanol, and use a glass rod to scrape the conductive carbon paste (CCI-305L type provided by Shenzhen Qiandai Electronic Materials Co., Ltd.) onto the conductive plastic film. Then put it into a drying oven and bake it at 150° C. for 0.5 h to deposit a carbon film with a thickness of 60 nm on its surface to obtain a flexible counter electrode conductive plastic film/graphite.

The flexible TiO ₂ photoanode and the flexible counter electrode conductive plastic film/graphite are bonded together by heating with a sarin film, and then the _DMPII ( 1,2-dimethyl-3-propylimidazolium iodide) and 0.5mol/L TBP acetonitrile electrolyte is injected into the inside of the battery from the small hole reserved by the flexible counter electrode titanium foil/Pt, and then the small hole is used Epoxy plugged, that is, flexible dye-sensitized solar cells made of organic conductive polymer films. Under the irradiation of 100Mw/cm ² xenon lamp, the measured short-circuit current of the battery is 3.01mA/cm ² , the open-circuit voltage is 0.62V, the filling factor is 0.45, and the photoelectric conversion efficiency is 0.84%.

Example 5

Select a PET substrate with a thickness of 175 μm, wash it with detergent and absolute ethanol, and coat its surface with a polythiophene conductive layer with a thickness of 1 μm to obtain a sheet resistance of 12Ω/□ and visible light transmittance 81% organic conductive polymer film. The selected polythiophene conductive polymer is a mixture of CLEVIOS PH750 and CLEVIOS PH1000 produced by Bayer, and its preparation method can adopt the method disclosed in the above-mentioned patent.

Use Zn(Ac) ₂ ·2H ₂ O to prepare 0.15mol·L ^-1 absolute ethanol solution, reflux at 90°C for 4 hours, add LiOH·H ₂ O powder at 0°C to make the concentration 0.2 mol·L ^-1 , stirred at this temperature for 25 minutes to form a colloidal solution of ZnO nanoparticles. Centrifuge in a high-speed centrifuge for 15 minutes, add absolute ethanol to the precipitated ZnO nanoparticles to wash, and then wash with a dilute nitric acid solution with pH=4 to obtain ZnO nanoparticle powder with a particle diameter of 10 nm. Then put it into a mortar containing a certain amount of ethanol, and weigh 3.6g of nano-titanium dioxide P25 powder produced by Degussa into the mortar, mix and grind evenly, and then magnetically stir for 4h to obtain a ZnO/TiO ₂ mixed slurry. The mixed paste was printed on the conductive layer of the organic conductive polymer film, and a ZnO/TiO ₂ film with a thickness of about 14 μm was obtained after natural drying. Then a pressure of 120MPa is applied to it to prepare a nano-ZnO/ _TiO2 porous film. Immerse the prepared ZnO/TiO ₂ porous film in 4×10 ^-5 mol/L of D205 dye in absolute ethanol, after absorbing for 24-36h, wash it with absolute ethanol, and dry it with cold wind to obtain a flexible film. ZnO/ _TiO2 photoanode.

A titanium foil with a thickness of 75 μm was selected, cleaned with detergent and absolute ethanol, and the Pt slurry containing the main components of chloroplatinic acid and terpineol was scraped onto the titanium foil with a glass rod, and then dried naturally. Put it into a muffle furnace and sinter at 450°C for 0.5h to deposit a layer of Pt mirror with a thickness of 60nm on its surface, that is, to prepare a flexible counter electrode titanium foil/Pt.

The flexible TiO ₂ photoanode and _the flexible counter electrode titanium foil/Pt were bonded together by heating with sarin film, and then DMPII (1 , 2-dimethyl-3-propylimidazolium iodine) and 0.5mol/L TBP's 3-methoxypropionitrile electrolyte is injected into the interior of the battery from the small hole reserved by the flexible counter electrode titanium foil/Pt, Then the small hole is blocked with epoxy resin, and the organic conductive polymer film flexible dye-sensitized solar cell is made. Under the irradiation of 100Mw/cm ² xenon lamp, the measured short-circuit current of the battery is 3.26mA/cm ² , the open-circuit voltage is 0.61V, the fill factor is 0.49, and the photoelectric conversion efficiency is 0.97%.

Claims (5)

1. flexible dye-sensitized solar battery, comprise compliant conductive substrate, dye-sensitized nano semiconductor porous film, electrolyte and flexible to electrode, it is characterized in that, described compliant conductive substrate is the organic conductive thin polymer film that applies organic conductive polymer coating at the high molecular polymer base material, the thickness of described organic conductive polymeric layer is 0.1～3um, and described DSSC is for setting gradually organic conductive polymer coating, nano porous semiconductor layer, electrolyte layer and flexible to electrode at the high molecular polymer base material;

Preparation is carried out as follows:

At first apply one deck organic conductive polymer (2) at high molecular polymer base material (10), namely make organic conductive thin polymer film flexible parent metal after the oven dry; Then print in the above one deck nano porous semiconductor (6), after any one method K cryogenic treatment in ultra-violet radiation method, hydrothermal method, mechanical compression moulding, electrophoretic deposition, to the organic conductive thin polymer film soft-light anode that obtains carry out dye sensitization and with flexibility to electrode (5) assembled battery, then the aperture of electrolyte (4) being reserved electrode from flexibility is injected into inside battery, can obtain the flexible dye-sensitized solar battery take the organic conductive thin polymer film as substrate after the encapsulation;

Nano porous semiconductor film in the described dye-sensitized nano semiconductor porous film is the nanocrystalline TiO of broad-band gap ₂, the compound formed film of one or both semiconductors among the ZnO;

Sensitizing dyestuff in the described dye-sensitized nano semiconductor porous film is any one among N3, N719 or the Z907.

2. according to the described flexible dye-sensitized solar battery of claim l, it is characterized in that the organic conductive polymer is any one in polypyrrole, polythiophene, the polyaniline in the described organic conductive thin polymer film.

3. flexible dye-sensitized solar battery according to claim 1 and 2 is characterized in that, the square resistance of described organic conductive thin polymer film is 10～400 Ω/, and visible light transmissivity is greater than 78%.

4. flexible dye-sensitized solar battery according to claim 3 is characterized in that, described electrolyte is liquid electrolyte.

5. flexible dye-sensitized solar battery according to claim 4 is characterized in that, described flexibility to electrode for being that conductive plastic film or the metal forming conductive base of 0.05～0.2mm is coated with platinum or the carbon film that a layer thickness is 4～200nm at thickness.

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