CN100355090C - Stereo absorption filament integrated dye sensitization solar cell - Google Patents

Abstract

A three-dimensional light-absorbing filamentous integrated dye-sensitized solar cell, which includes a transparent glass tube, and a plurality of coated metal wires are placed in a staggered arrangement in the transparent glass tube. The coated metal wires are made of metal wires or conductive fibers resistant to electrolyte corrosion. Coating process, coated with wide-bandgap nanocrystalline semiconductor thin film oxides for charge separation, which is prepared by absorbing sensitizing dyes after heat treatment. After the coated metal wires are connected in parallel, the electrodes are drawn out as the photoanode of the solar cell. The transparent glass tube is also inside A counter electrode for catalysis and electron transmission is placed, and the transparent glass tube is filled with an electrolyte with redox effect, and its port is sealed with a sealant. The solar cell of the invention can increase the effective light-absorbing area of the space on the same area, thereby increasing the output power of the solar cell per unit area, and saving the occupied area of the solar cell.

Description

A stereo light-absorbing filamentous integrated dye-sensitized solar cell

technical field

The invention relates to the field of photovoltaic utilization of solar energy, in particular to a solar cell.

Background technique

Since the solar cell was invented in 1954, solar cells made of various materials (including silicon, GaAs, CIS, and dye-sensitized solar cells, etc.) have all adopted planar structures, although scientists have been working to improve the efficiency of planar solar cells. , but based on the calculation of the highest theoretical efficiency of monocrystalline silicon solar cells of 50%, the area it occupies is still huge, and it is difficult to meet all the electricity needs of a family even if the entire roof of the villa is used. With the growth of population, people will inevitably build more high-rise buildings, and the roof and land area that can be used to install solar cells will inevitably be less. Making full use of sunlight is a crucial issue. As we all know, the photosynthesis of chlorophyll in plants in nature has a very low utilization efficiency of solar energy, less than 1%, which is far lower than the efficiency of current solar cells, but the important difference between it and lichens, mosses and other plants is that the growth of trees uses The three-dimensional light-absorbing structure of fractal growth has been realized, and the most reasonable utilization of solar energy has been achieved, which has played a useful reference role in the development of new dye-sensitized solar cells.

Contents of the invention

The object of the present invention is to provide a filamentous integrated dye-sensitized solar cell with three-dimensional light absorption, which can increase the effective light absorption area of the space on the same area so as to improve the output power of the solar cell per unit area and save solar cells of floor area.

A three-dimensional light-absorbing filamentous integrated dye-sensitized solar cell provided by the present invention includes a transparent glass tube, and a plurality of coated metal wires are placed in a staggered arrangement in the transparent glass tube. The anode, the transparent glass tube also has a built-in counter electrode that plays a role in catalysis and electron transmission. The counter electrode is placed in the center of the transparent glass tube or evenly distributed around the coated metal wire. The transparent glass tube is filled with an electrolyte with redox effect , the port of which is encapsulated by a sealant; the coated metal wire is made of a metal wire or conductive fiber resistant to electrolyte corrosion through a coating process, and is plated with a wide-bandgap nanocrystalline semiconductor thin film oxide that acts as a charge separation function. After heat treatment Prepared by adsorption of sensitizing dyes.

In the above technical scheme, the metal wire is titanium, nickel, gold, tungsten, platinum, molybdenum or manganese wire; the electrolyte with redox effect is an electrolyte containing I- ^and _I2 ; the The coating process adopts techniques such as pulling film forming method or screen printing; the nanocrystalline semiconductor thin film oxide is nanocrystalline TiO ₂ or SnO ₂ and other wide bandgap semiconductor thin films; It is platinum wire, nickel wire, carbon wire or metal wire or conductive fiber coated with platinum, nickel or carbon film.

When in use, wires with good conductivity (such as copper) are respectively welded to the positive and negative electrodes of the solar cell of the present invention or bonded with conductive glue or conductive paste, then lead out, connected to a load, and then work under light.

The increase in the effective light-absorbing area of the filamentary integrated three-dimensional light-absorbing structure can be explained by geometric knowledge. It can be seen from Figure 1 that a cylinder with the same area is 1+4H/D times the light-absorbing area of a plane. When D is constant, the light-absorbing area It will increase proportionally with H, divide the cylinder into small cylindrical filaments with infinitely thin diameters, and arrange them with gaps to realize spatial three-dimensional light absorption. The light-absorbing area of the metal wire head is negligible, and the increase of its light-absorbing area can be expressed as ² times of 4ndH/D. Taking the titanium wire with a diameter of 100 μm and a length of 10 cm coated with a 30 μm titanium oxide film as an example, 1 ^cm2 can Arrange 600 to achieve the most reasonable light absorption, and the effective area of spatial three-dimensional light absorption will be increased by about 300 times compared with the same plane area. The finer the diameter of the metal wire used, the further the effective light-absorbing area will be increased.

The traditional planar sandwich dye-sensitized solar cell with conductive glass as the substrate includes a three-layer structure: the first layer is a heat-treated wide-bandgap porous nanocrystalline oxide film ( Such as TiO ₂ ), the sensitizing dye that acts as a charge separation on the surface of the nanocrystalline oxide film constitutes a photoanode; the second layer is filled with an electrolyte solution that has a redox effect (such as I ^- and I ₂ ), The third layer is a transparent conductive glass coated with a catalyst (such as platinum, nickel, carbon) to form the counter electrode.

The working principle of the present invention is basically the same as that of the dye-sensitized solar cell with conductive glass as the substrate. When the light irradiates the sensitizing dye, photogenerated electron-hole pairs are generated, and the electrons and holes are separated by TiO ₂ , and I ^- The ions are oxidized to I ₃ ^- ions by the holes, and the electrons enter the load through the coated metal wire, and then return to the electrolyte through the counter electrode wire, and the I ₃ ^- ions in the electrolyte are reduced to I ^- by the holes ions, completing a cycle.

Compared with the traditional planar sandwich dye-sensitized solar cell, the stereo light-absorbing filamentous integrated dye-sensitized solar cell of the present invention has the following advantages:

1. Due to the use of a three-dimensional light-absorbing filamentary integrated structure similar to a tree trunk, the surface area for receiving sunlight is increased, and as long as the length of the coated metal wire can be infinitely extended or the diameter can be reduced to increase the number of coated metal wires technically , the light-absorbing surface area will be further increased, thereby achieving the problem of saving the occupied area of solar cells;

2. Traditional dye-sensitized solar cells use conductive glass as the substrate, while the current transparent conductive film is made of semiconductor materials such as SnO ² doped with F or indium tin oxide, which has a large square resistance and is difficult to prepare large-area solar cells. (less than 1cm ² ), and the present invention uses a corrosion-resistant, low-resistance metal wire as the carrier of electron transmission, which will further reduce the internal resistance of the solar cell, thereby improving efficiency;

3. In addition to the disadvantage of high electrical resistance of the conductive glass, the traditional dye-sensitized solar cell, due to the limitations of the current technology, the large-area conductive glass is not smooth, so there are technical difficulties in large-area packaging; and the present invention encapsulates the electrolyte in In tubular containers, there have been successful examples in dry batteries, etc.;

4. If each three-dimensional light-absorbing solar cell is arranged in a hedgehog spherical shape, when the sun rises from the east and sets in the west, the three-dimensional light-absorbing solar cells can receive sunlight in all directions, and the application is more efficient and convenient. The battery can only absorb sunlight from the front.

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

Description of drawings

Figure 1 is a schematic diagram illustrating the geometry of the increase in the effective light-absorbing area of the filamentary integrated three-dimensional light-absorbing structure;

Fig. 2 is a structural schematic diagram of the filamentous integrated dye-sensitized solar cell with stereo light absorption of the present invention;

Fig. 3 is a working schematic diagram of solar cells arranged in a hedgehog spherical form according to the present invention.

Detailed ways

As shown in Figure 2, a kind of three-dimensional light-absorbing filamentous integrated dye-sensitized solar cell provided by the present invention includes a transparent glass tube 1, and a plurality of coated metal wires 2 are placed in the transparent glass tube 1 in a staggered arrangement. After wire 2 is connected in parallel, the electrode is drawn out as the photoanode of the solar cell. The counter electrode 3 which plays a role in catalysis and electron transmission is also placed in the transparent glass tube 1. The transparent glass tube 1 is also filled with an electrolyte 4 with redox effect. The port is encapsulated by a sealant; the coated wire 2 is a metal wire or conductive fiber that is resistant to electrolyte corrosion through a coating process, and is coated with a wide-bandgap nanocrystalline semiconductor thin film oxide that acts as a charge separation function, and is adsorbed and sensitized after heat treatment. made from dyes. In the above technical scheme, the metal wire is titanium, nickel, gold, tungsten, platinum, molybdenum or manganese wire; the electrolytic solution 4 with redox effect is an electrolytic solution containing I- ^and _I ; the coating process adopts the pulling film forming method Or screen printing and other processes; nanocrystalline semiconductor thin film oxides are nanocrystalline TiO ₂ or SnO ₂ and other wide bandgap semiconductor thin films; the counter electrode 3 that plays a role in catalysis and electron transmission is platinum wire, nickel wire, carbon wire or platinum-coated , nickel or carbon thin film metal wires or conductive fibers are placed in the center of the transparent glass tube 1 or evenly distributed around the coating metal wire 2 .

If the solar cells of the present invention are arranged in a hedgehog spherical form as shown in Figure 3, when the sun rises from the east and sets in the west, the solar cells that absorb light in the form can receive sunlight in all directions, and the application is more efficient and convenient.

Example 1

Put 12 grams of commercial nano-titanium dioxide P25 powder produced by Germany Degussa company into a mortar and grind it, and add 4 ml of isopropanol solution containing 10% acetylacetone drop by drop, then add 10 ml of water drop by drop to continue grinding, and add 0.2 ml Triton X-100 was added to the suspension to prepare a titanium oxide sol with a concentration of 54.54%.

230 titanium wires with a diameter of 100 μm and a length of 7 cm were coated with a 30 μm thick titanium oxide film at a pulling speed of 10 mm per second by the pulling method, and about 1 cm of titanium wire was reserved as a conductive electrode. Heat treatment for 30 minutes.

Put the coated titanium wire into an ethanol solution containing 3×10 ^-5 moles of N719 ruthenium organic dye, heat it to 80°C and soak for 3 hours, take it out, wash it with ethanol, and store it in a dry and light-proof environment.

Use 100μm copper wire to wrap around the photoanode of reserved titanium wire, stick it firmly with conductive silver paste, keep it in a vacuum drying oven at 150°C for 1 hour to cure, and treat the platinum wire of the counter electrode in the same way, and coat the copper lead wire with The upper insulating epoxy resin glue is cured to ensure that it is not short-circuited with the photoanode.

The platinum wire is placed in the center of the transparent glass tube, and the photoanode is placed in the transparent glass tube and arranged around the platinum wire with a certain gap. The port of the transparent glass tube is sealed with glass glue and two small holes are reserved. The acetonitrile electrolyte containing 0.3m/L LiI and 0.015m/L _I2 was poured into a transparent glass tube, and then the small hole was blocked with epoxy glue.

Connect the lead-out positive and negative electrodes to the load to work under light.

Example 2

Mix 125mL of isopropyl titanate and 20mL of isopropanol evenly, put it into a separatory funnel, add dropwise to 750mL of deionized water containing 5.3mL of 70% nitric acid within ten minutes and stir vigorously. Continue to stir for 8 hours to form a transparent nano- _TiO2 colloidal solution, then put it into a high-temperature and high-pressure reactor at 200 ° C for a constant temperature reaction for 12 hours, and concentrate the prepared nano- _TiO2 sol to a concentration of 45% TiO2 by rotary evaporation. ₂ Sol.

70 nickel wires with a diameter of 100 μm and a length of 11 cm were plated with a 25 μm thick titanium oxide film at a pulling speed of 10 mm per second by the pulling method, and a nickel wire of about 1 cm was reserved as a conductive electrode. Heat treatment for 30 minutes.

Put the coated nickel wire into an ethanol solution containing 5×10 ^-5 mol/L N719 ruthenium organic dye, place it at room temperature for 72 hours, take it out, wash it with ethanol, and store it in a dry and light-proof environment.

Use 100μm copper wire to wind on the photoanode with reserved nickel wire, and stick it firmly with conductive silver paste, keep it in a vacuum oven at 150°C for 1 hour to cure, and treat the platinum wire of the counter electrode in the same way, and coat the copper lead wire with The upper insulating epoxy resin glue is cured to ensure that it is not short-circuited with the photoanode.

The inner diameter of the transparent glass tube is 4 mm, and the length is 10 cm. The photoanodes are placed in the transparent glass tube and arranged in a certain gap. Four 100 μm counter electrode platinum wires are evenly distributed in it. The port of the transparent glass tube is sealed with glass glue and reserved. Two small holes, the acetonitrile electrolyte containing 0.5mol/L LiI, 0.03mol/L _I2 and 1mol/L tetra-tert-butylpyridine is driven into the transparent glass tube with a syringe, and the small holes are ringed Oxygen glue is blocked.

Connect the lead-out positive and negative electrodes to the load to work under light.

Claims (6)

1, a kind of filament integrated dye sensitization solar cell of stereo absorption, it is characterized in that including a transparent glass tube (1), push the wrong discharging in the transparent glass tube (1) and be equipped with many plated film wires (2), plated film wire (2) back in parallel extraction electrode is as the light anode of solar cell, transparent glass tube (1) also be built-in with catalysis and electric transmission effect to electrode (3), to electrode (3) be placed on transparent glass tube (1) central authorities or be distributed on plated film wire (2) around, in the transparent glass tube (1) and be filled with the electrolyte (4) of tool redox, its port is encapsulated by fluid sealant; Described plated film wire (2) is to pass through coating process by the wire of electrolyte resistance corrosion or conductive fiber, has plated the broad-band gap nanometer crystal semiconductor film oxide of electric charge centrifugation, makes at absorption sensitizing dyestuff after Overheating Treatment.

2, the filament integrated dye sensitization solar cell of stereo absorption according to claim 1 is characterized in that described wire is titanium, nickel, gold, tungsten, platinum, molybdenum or manganese silk.

3, the filament integrated dye sensitization solar cell of stereo absorption according to claim 1 is characterized in that describedly having the electrolyte (4) of redox for containing I ^-And I ₂Electrolyte.

4, the filament integrated dye sensitization solar cell of stereo absorption according to claim 1 is characterized in that described coating process adopts pulling film forming method or silk-screen printing technique.

5, the filament integrated dye sensitization solar cell of stereo absorption according to claim 1 is characterized in that described nanometer crystal semiconductor film oxide is nanocrystalline TiO ₂Or SnO ₂Wide-band gap semiconductor thin film.

6, the filament integrated dye sensitization solar cell of stereo absorption according to claim 1, it is characterized in that described play catalysis and electric transmission effect to electrode (3) for platinum filament, nickel wire, carbon filament or be coated with the wire or the conductive fiber of platinum, nickel or carbon film.

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