JP2006216959A - Solid photocell device including monolithic film of semiconductor material having tubular pore - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photocell device having improved characteristics and performance, especially having higher photocell efficiency. <P>SOLUTION: In the solid photocell device including a constituent of a transparent n-type semiconductor, a constituent of an absorber and a constituent of a transparent p-type semiconductor, the photocell device includes a monolithic film (1) of either one of the two n-type and p-type semiconductor constituents. The monolithic film (1) has pores each of which has a channel shape extended so as to cross between both the surfaces of the monolithic film through the whole thickness of the film and the inner surface of the pore is coated with a thin film (2) consisting of the absorber material. The pore is filled with the other semiconductor constituent (3) at volume percentage of at least 20%, preferably more than 50%. The monolithic film is inserted preferably between two conductive substrate layers (4, 6) and at least one of the conductive substrate layers (4, 6) is transparent. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a new solid state photovoltaic device fabricated with a new intrusive form of nanostructure.

  A solid-state photovoltaic device having a nanocrystalline intrusion form, comprising a porous film substrate made of a transparent n-type semiconductor, comprising a thin film of an absorber material and a porous film substrate coated with a transparent p-type semiconductor Are known.

Traditional photovoltaic devices are based on the joining of two semiconductor layers. One is p-type (main carriers are holes or positive charges), and the other is n-type (main carriers are electrons or negative charges). The most widely used photovoltaic cell device is made of silicon (Si), which is a homojunction of two Si layers, doped with impurities so that one of the two layers is n-type. It is. Other known devices, the two layers is based on heterojunction of different semiconductor materials, for example, a device comprising a layer of CdTe / CdS or CuInSe ₂ / CdS corresponds to this. A common feature of these devices is that the semiconductor is manufactured according to the form of a flat stacked layer. In addition to these two semiconductor layers, the final product device may be provided with other additional layers such as contact layers for front and back contacts, buffer layers, etc. Forms based on flat stack layers are always kept. The operating principle of this device is as follows. That is, when solar radiation enters the junction, photons are absorbed by both semiconductor layers, which turn into electron / hole pairs. That is, the charge is separated, and the electrons move to the n-type contact and the holes move to the p-side contact.

One problem with this type of junction is that materials with high purity and very well controlled doping levels must be used. This is to avoid degradation of the performance of the photovoltaic cell due to charge recombination. In fact, different charge carriers tend to move along the same layer of semiconductor material and recombine in the presence of recombination centers such as impurities, lattice defects, crystal grains or grain boundaries of crystals, etc. Therefore, it is not converted into electricity. This recombination phenomenon is an important loss factor that affects the performance of the photovoltaic cell. Processes involving high purity and precise doping (impurities) involve the use of complex and sophisticated techniques and greatly increase manufacturing costs. Cost is a critical constraint when designing this type of photovoltaic device for use in large-area panels used on residential roofs as residential photovoltaic generators. Typical nominal power for such devices is on the order of 1-5 kilowatts (at the maximum power point), which corresponds to a panel area on the order of 10-30 m ^{2 for} a typical nominal conversion efficiency on the order of 10%.

  Recently, another technology that converts solar radiation into electricity has emerged, with the advantage of low manufacturing costs as an advantage. In particular, new types of photovoltaic cells have been proposed (see Non-Patent Document 1 and Non-Patent Document 2). It is mainly based on three kinds of solid inorganic materials arranged in an intrusive form and is different from the form of a flat stack layer. The device is a “transparent” n-type semiconductor substrate (“transparent” means that it absorbs little radiation at wavelengths greater than 400 nanometers), which is in the form of a porous layer. And the inner surface of this layer is coated with a thin film of an absorbent semiconductor material ("absorber" means that it absorbs solar radiation with a wavelength in the range of 300-1200 nm), The pores of this layer are finally filled with a “transparent” p-type semiconductor material.

  This device has a penetrating configuration. Because it utilizes an initial matrix consisting of a porous layer of n-type semiconductor made from nanometer or micrometer sized crystals or particles, the absorber material is composed of two semiconductor materials (one is This is because the thin film exists between the n-type and the p-type.

  The operating principle of this device is as follows. That is, solar radiation (photons) is absorbed only by the absorber material, and then electrons move towards a transparent (or non-absorbing) n-type semiconductor, while positive charges (or holes) are p-type semiconductors. It is a mechanism that moves in the direction. According to this principle, the transport of charge carriers with opposite signs will occur in two separate phases, which theoretically greatly reduces the loss of photovoltaic performance due to charge recombination. The porous nanocrystal film or microcrystal film of the semiconductor substrate had to be used because a sufficient internal area was provided so that a sufficient amount of absorber material was included in the film with respect to the incident area. Because of that.

  The basic advantages of the forms proposed in these documents (Non-Patent Document 1 and Non-Patent Document 2) with respect to other penetration modes are as follows. First, due to the fact that a thin coating layer of absorber material is used rather than molecules (molecules in the well-known dye-sensitized cells) or "quantum dots" (fine insulating particles on the order of a few nanometers) It is the point that it is possible to obtain photocurrent and photovoltaic cell efficiency (it is possible to mount a larger amount of absorber material and direct contact between two semiconductors of n-type and p-type Because there is no recombination at the interface because there is no). Second, the fact that a solid inorganic material is used makes it possible to obtain long-term stability. Other technologies use liquid electrolytes, or organic hole conductor materials, even in the solid state, and these electrolytes and conductor materials are high temperature and strong solar radiation ( It is known to be sensitive to, and deteriorates, typical conditions of outdoor and rooftop installation.

Finally, this new form allows the production of photovoltaic devices at low manufacturing costs. The reason is that this new form uses inexpensive materials, does not require very high purity materials, and the manufacturing technology is not expensive (especially used in the manufacture of silicon-based devices). In contrast to the technology used, there is no need to use high vacuum techniques.
Siebentritt, Koenenkamp et al., "The 14th European Photovoltaic Solar Energy Conference and Exhibition Proceedings" (14th European Photovoltaic Solar Energy Conference & Exhibit, 1997) . 1823 Lost, Koenenkamp et al., “The 2nd World Conference on Photovoltaic Energy Conversion & Exhibition Photovoltaic Solar Energy Conversion 98” (Vienna, 1998) [Vienna, 1998] p. 212

However, devices with this nanostructured morphology made so far show very low photovoltaic efficiency. Examples based on this concept have been introduced in several literatures (“Tenakone et al., Journal of Physics D: Applied Physics (J. Phys. D: Appl. Phys.)”, Vol. 31 ( 1998), p. 2326 "and" Kaiser, Koenenkamp et al., "Solara Energy Materials & Solar Cells," Vol. 67 (2001), p. 89 "). Make a porous film of TiO ₂ (consisting of crystals or grains) and then deposit by electrodeposition or ILGAR technique (impregnated with Cu and In precursors and then treated with high temperature H ₂ S gas), respectively. An absorber made of Se or CuInS ₂ is coated, and a p-type made of CuSCN Is filled or coated with a transparent semiconductor. Although the spectral sensitivity characteristics or quantum efficiency was revealed, short-circuit photoelectric current is extremely low ^(10-3 or 10 -4 ^{mA /} cm ² or less) and / or the current-voltage curve The photoelectric conversion efficiency was extremely low because of the very low fill factor (0.1 or less).

A very similar type of device has been reported recently ("Levy-Clement et al.," 205th Electrochemical Meeting Abstracts [San Antonio, USA, 2004] ", p. 402"), which is made from a ZnO / CdSe / CuSCN material, in which the porous n-type semiconductor ZnO has a width greater than 100 nm and a length of 1-2 micrometers. The reporter stated that the solar cell efficiency was about 2% at a solar radiation intensity of 360 W / m ² , and the reason for this improvement was very Attributed to the use of a porous layer with a coarse (and large) pore size However, this structure has the problem that the roughness factor (roughness factor is the ratio between the internal surface area and the incident area of the porous layer) is small and lower than 10. Limiting the maximum photocurrent that can be (because the maximum photocurrent is directly related to the amount of absorber present in the layer) and thus limiting the maximum photovoltaic efficiency that can be obtained.

  It is an object of the present invention to provide a photovoltaic device having improved properties and performance, particularly better photovoltaic efficiency.

  The solution proposed by the present invention is based on the photovoltaic device of the previous concept consisting of three solid components (two transparent semiconductors of n-type and p-type and one absorber). The solution of the present invention proposes a new intrusion configuration that can achieve higher photovoltaic cell efficiency while retaining the potential advantage of low manufacturing cost by this structural scheme.

More precisely, the present invention comprises the following components:
A transparent solid n-type semiconductor element;
An absorbent element;
A new form of solid photovoltaic device comprising a transparent solid p-type semiconductor element is proposed, in which a monolithic film of either two n-type or p-type semiconductor elements, respectively, It has pores with tubular shapes that extend across the entire thickness of the monolithic membrane across the entire thickness of the membrane, and the inner surface of the pores is coated with a thin film of the absorbent material. The pores are filled with another semiconductor by a volume ratio of at least 20%, preferably more than 50%, and the monolithic film is preferably inserted between two conductive substrate layers And at least one of the conductive substrate layers must be transparent.

  The expression “monolithic film” means a continuous film. More specifically, unlike a film made by bonding or agglomerating particles or crystals of the semiconductor material, that is, unlike a film in which a gap between the particles or crystals forms pores, the semiconductor It means a continuous film without material grain boundaries.

  The channel constitutes a kind of tunnel extending along the entire thickness of the monolithic film.

  The tubular pores can extend along the thickness of the monolithic membrane, perpendicular to the surface of the monolithic membrane, with a slight inclination, or in a more gently curved manner. The form of tubular pores extending from one side to the other along the thickness of the membrane provides a more uniform coating of the entire internal surface of the pores with a thin coating of absorbent material during coating. For easy entry.

  In the special case of an inclined tube, the tube forming the pores can have an inclination of less than 30 ° with respect to a direction perpendicular to the surface of the monolithic membrane.

  The tubular shape preferably has a shape remarkably close to a cylindrical shape, and the cylindrical shape preferably has a cross section remarkably close to a circular or elliptical shape.

  The expression “significantly close” means that the cross-sectional dimension of the channel across the length of the channel along the thickness of the monolithic membrane, and more specifically, the diameter of the channel varies in the range of less than 20% along the length of the channel It means to do.

  The cylindrical pores preferably extend completely perpendicular to the surface of the monolithic membrane. In this case, the length of the pores substantially matches the thickness of the monolithic membrane. This simplifies the final filling of the pores with the second semiconductor material.

  The pores preferably have a completely smooth inner surface, and the roughness coefficient is preferably less than 2. This makes it possible to obtain a uniform absorber film having a uniform film thickness and to obtain good interface contact between the absorber and the semiconductor.

  In one preferred embodiment of the present invention, the cross-sectional dimensions of the pores, more precisely the diameter of such pores, is 10 to 100 nm before coating the absorber, and the thickness of the absorber coating Is preferably 1 to 25 nm, preferably 2 to 10 nm, and uniform. This allows electrons and holes to move rapidly towards n-type and p-type semiconductors, respectively, and avoids any charge recombination inside the absorber coating layer.

  The roughness coefficient of the monolithic film is preferably greater than 50, and more preferably greater than 100.

  “Roughness factor” means the ratio between the internal surface area of a porous film (according to the internal surface area of the pores present in the structure) and the incident area of the film on the substrate.

Considering a typical value of the absorption coefficient of the absorber material (at best about 10 ⁻⁵ cm ⁻¹ ), if the roughness coefficient of this nanostructured monolithic film is greater than 50, solar radiation of 1000 W / cm ² It is possible to obtain a short-circuit photocurrent greater than 15 mA / cm ² when irradiated with, which may result in a photovoltaic cell efficiency greater than 10%.

  Preferably, the cross-sectional dimension of the pores or the average diameter of the pores is 20 to 50 nm, the average distance between the pores is 2 to 20 nm, and the thickness of such a monolithic membrane is 2 to 10 μm. . This is the most favorable geometric condition to achieve a roughness factor greater than 50 for a monolithic membrane.

  The expression “average distance between pores” means the average thickness of the wall surfaces between the pores, and an aggregate of such wall surfaces constitutes the monolithic film.

  This monolithic film is preferably made of an n-type transparent semiconductor.

  More preferably, another transparent semiconductor component layer is provided between the monolithic film and the at least one conductive layer substrate.

  The device according to the invention is in particular a layer of another semiconductor component which is non-porous and transparent and is provided between the monolithic film and a conductive layer substrate which acts as a “light-receiving surface electrode” Contains layers of. This thin layer (referred to as the shielding layer) is made from the same semiconductor material as the monolithic film, or from the same type (respectively n-type or p-type) but from a different semiconductor material from the monolithic film material. This shielding layer can prevent any short circuit between the semiconductor filling the pores and the transparent conductive layer substrate acting as a “light-receiving surface electrode”. The “light-receiving surface electrode” of the conductive substrate can be made from a commercially available transparent conductive glass.

  Another embodiment of the present invention includes a layer of another semiconductor component that is thicker than 10 nm and is provided between the monolithic film and the “back contact” of the conductive layer substrate. This thin overlayer is made from the same semiconductor material as the material filling the pores, or from a semiconductor material of the same type (respectively n-type or p-type) but different from the material filling the pores Made. The overlying layer can prevent any short circuit between the monolithic film semiconductor and the “back electrode” of the conductive layer substrate. The “back contact” of the conductive substrate can be made from any other conductive material such as carbon or metal.

  From the above, the main point of the solution proposed by the present invention in order to solve the above problems is that two “transparent” and solid semiconductor components (“transparent” hardly absorbs solar radiation with a wavelength exceeding 400 nm. ) And solid state absorber semiconductor materials ("absorber" means a material that significantly absorbs solar radiation with a wavelength in the range of 400-1200 nm), and also these The material is in the arrangement of new nanostructured intrusions. This new nanostructure penetration configuration facilitates sequential sequential deposition in the penetration mode of these three major components and improves the interfacial contact between the layers of these components. This is a necessary condition for obtaining good photoelectric conversion efficiency.

  The advantage of the new photovoltaic device provided by the present invention is that the photovoltaic cell uses materials that do not require high purity and can be manufactured by low-cost manufacturing techniques (particularly for silicon-based devices). Therefore, a high conversion efficiency can be exhibited while maintaining a low manufacturing cost. This new concept device also allows selection from a much wider range of absorber materials than would be the case for devices based on flat layers. This is because in principle there is no need to use materials with exceptional inherent properties. Furthermore, this new device has the potential to maintain its stability very long because it uses solid materials, and preferably inorganic materials.

  The outline of the new form is shown in FIG.

  The main points of the new form lie mainly in monolithic matrix membranes with nanostructures with cylindrical pores of either of two “transparent” semiconductors.

  This monolithic matrix film is preferably formed on the surface of a transparent conductive substrate such as commercially available glass made of a transparent conductive oxide.

  In another embodiment of the present invention, the channel-shaped pores as described by the present invention that penetrate the full thickness of the monolithic membrane have perpendicular or constant inclination (inclination close to 90 °) to them. It may be connected to other tubular pores.

  The volume remaining in the pores after the absorber has been coated must subsequently be filled with another semiconductor of the opposite type to that of the monolithic membrane (p-type if the monolithic membrane is n-type). The pore filling rate should preferably be greater than 20% of the free volume, more preferably greater than 50% (ideally 100%).

  The device should eventually be trapped and sealed to avoid any possible degradation due to moisture or airborne contaminants.

  In addition to this special form, the three components must satisfy specific conditions, in particular the matching conditions of the respective energy bands. Taking the semiconductor band model as a first approximation, the conduction band of the absorber shows a smaller energy level than the conduction band of the n-type semiconductor (in most conventional types used, the energy level). Has a negative value when the vacuum level is zero), the valence band of the absorber must be a larger positive value than the valence band of the p-type semiconductor. All this is to enable the injection of electrons and holes respectively.

  In a preferred embodiment of the present invention, the three components should be inorganic materials, which provides the potential advantage of providing long durability for outdoor applications, particularly for applications installed on the roof of a house .

Well-known examples of “transparent” n-type semiconductor materials are several metal oxides such as TiO ₂ , ZnO, or SnO ₂ .

Well-known examples of “transparent” p-type semiconductor materials with energy levels compatible with n-type semiconductors include some materials of Cu (I) such as CuSCN, CuI or CuAlO ₂ delafosite, and some It is a metal oxide.

  Examples of absorber inorganic materials having a high absorption coefficient in the wavelength range between 400 nm and the absorption edge in the interval between 600 and 1200 nm include some colored metal oxides and many metal chalcogenides (sulfides, Selenide, telluride).

  The expression “absorption edge” is used herein to mean the value of the wavelength at which the material significantly absorbs solar radiation at wavelengths below that value.

  The monolithic membrane with pore morphology proposed by the present invention, and more specifically the monolithic membrane with nanostructures proposed by the present invention can be manufactured using low cost techniques.

Recently, methods have been proposed for producing particles or monolithic membranes with porous nanostructures by creating pores of various shapes. The main point of this technique is that a surfactant is used as a structure indicator or template. This technique is used for metal oxide type materials or metals, initially for the production of particles with internal pores, and most recently for the production of porous layers with regularly arranged pores. Or it is used for applications in the optical field. Examples of materials from which monolithic membranes having regularly arranged pores are manufactured include Pt metal (references “GS Attard et al.,“ Science ”, Vol. 278 ( 1997), p. 838 ”), SiO ₂ (literatures“ MC Goncalves ”and“ GS Attard ”,“ Advanced Materials Science Review (Rev. Adv). Mater. Sci.), Vol. 147 (2003), p. 164 "), and TiO ₂ (reference" KM Coakley, et al., "Advanced Functional Materials (Adv). Funct. Mater.), Vol. 13 (2003), p. 301 "). Therefore, this type of structure (for example, the structure of TiO ₂ ) is incorporated in the present invention. It is possible to use.

  The absorption coating can be deposited using low cost deposition techniques such as chemical bath deposition or electrochemical deposition.

  Filling the free volume of the pores with the second “transparent” semiconductor can be accomplished by impregnating a solution of the dissolved material and then evaporating the solvent, or by impregnating the precursor solution of the material and spin coating. Or by using a low-cost technique such as electrochemical deposition.

  Further features and advantages of the present invention will become apparent from the description based on the drawings.

Certain embodiments of the present invention include the following features:
The first surface of the monolithic film (1) having pores (1 ₁ ) according to the present invention is a first substrate that acts as a front contact and is transparent and conductive, for example, conductive glass (4). Deposited on a first substrate, which is previously covered by a non-porous transparent shielding layer (5), which is preferably a monolithic membrane (1). Are made of the same semiconductor, and
The monolithic film (1) constitutes a film having a thickness of more than 1 μm, preferably 2 to 10 μm, and
The absorber layer (2) present on the inner surface of the pores has a thickness of 1 to 25 nm, preferably 2 to 10 nm; and
The packed bed (3) is filled with at least 20%, preferably more than 50%, of the pore volume; and
The second surface of the monolithic layer is covered by a second conductive substrate acting as a back electrode (6); and
Said filling layer (3), preferably, said monolithic layer (1), thicker coating layer than 10nm provided between the conductive layer of the second conductive substrate which acts as a back electrode (6) (3 ₁ ), And
The monolithic layer and its absorber and filler layers are confined between the conductive substrates acting as contacts;
It has the characteristics.

  The second conductive substrate acting as a back electrode may or may not be transparent and is preferentially fabricated from metal or carbon.

  Example 1 shows one case of a possible manufacturing method for a new device, Example 2 has a nanocrystalline structure and has pores of approximately the same size as the pore size of Example 1. 1 shows one case of a possible manufacturing method of a device with a form of prior concept.

The device was characterized by one of the most commonly used state of the art techniques. It is the current voltage (IV) curve of the device placed under irradiation. From this curve, the photovoltaic efficiency, which is the ratio of the electrical power generated by the device at the maximum power point to the power of the incident radiation, can be calculated. This efficiency was measured by a solar simulator connected to another device. The device response was evaluated under an irradiance of 1000 W / m ² corresponding to the reference sunlight AM1.5G. The bench test apparatus was calibrated according to standard procedures for photovoltaic devices commonly used in each authorized public authority.

  FIG. 3 shows the current-voltage curves for Example 1 (device with new nanostructures) and Example 2 (device based on the previous form with nanocrystal structures). Although the photovoltaic cell efficiency in either case is still low, the current-voltage curve corresponding to Example 1 shows better photovoltaic cell performance behavior than in Example 2. The low efficiency of Example 1 was chosen because the dimensional shape relationship of the matrix membrane is not yet favorable (membrane thickness is less than 1 micron and pore size is less than 10 nm). It can be seen that the material is not accurate.

The nanostructured monolithic film is made of TiO ₂ (n-type semiconductor), prepared using the surfactant template method shown in the literature, the absorber layer is made of CdS, and is deposited by chemical bathing. Filling with a p-type semiconductor composed of CuSCN was performed using an impregnation technique (current state of the art) with a CuSCN solution.

Manufacture of photovoltaic devices with a new form of nano-structure consisting of TiO _2, CdS, and CuSCN.

A commercially available transparent conductive glass (for example, with an F-doped SnO ₂ layer provided by Pilkington) is cut into 2.5 × 2.5 centimeter pieces, ethanol and Wipe with distilled water. A dense (non-porous) TiO ₂ layer about 50 nm thick is deposited on this substrate by spray pyrolysis. That is, a solution in which 10% by volume of titanium (IV) bis (acetylacetonato) diisopropoxide is dissolved in ethanol is sprayed on the surface of the glass substrate maintained at a high temperature of about 450 ° C. for 10 minutes. According to the method described in “Kavan et al.,“ Electrochim. Acta ”, Vol. 40 (1995), p643.” This layer has holes or positive charges toward the electrode collecting electrons. Acts as a shield to prevent movement.

Subsequently, a nano-structured porous TiO ₂ layer is deposited by the << immersion coating method >> using a solution containing a precursor and a surfactant as a template. The procedure in accordance with the document “Coakley et al.,“ Advanced Functional Materials (Adv. Funct. Mater.) ”, Vol. 13 (2003), p. 301 "or" Crepaldi et al., "J. American Chem. Soc., Vol. 125 (2003), p. The procedure is similar to that described in 9770 ". First, the following chemicals are mixed in a pan: 20 g ethanol, 1 g Pluronic << P123 >> surfactant (this is poly ( 3 block copolymer consisting of (ethylene oxide) -poly (propylene oxide) -poly (ethylene oxide), sold by Aldrich), commercially available concentrated hydrochloric acid 3 g (36 wt% aqueous solution), and Ti ethoxide .TiO ₂ film is (TiO ₂ precursor) 4g includes: the substrate, the solution and was precipitated by using a dip coating apparatus of the forward and reverse immersion rocking speed per 5 mm. then, the sample air dried for 24 hours at medium, then the thickness of the .TiO ₂ porous membrane was heated to 400 ° C. at a heating ramp per minute 1 ℃ 0.5 Mi Pores cylindrical with a .10nm smaller diameter was Ron, by scanning electron microscopy SEM, it is observed in the upper layer.

The absorber layer of Cd sulfide was deposited inside the porous TiO ₂ film by a method of sequentially immersing in different bath solutions using a chemical bath deposition technique. Four saucers with 50 ml of solution were used. One bath contained an aqueous solution of 0.05 M Cd (NO ₃ ) ₂ , the other bath contained an aqueous solution of 0.05 M Na ₂ S, and the remaining pan was filled with distilled water. A substrate with a TiO ₂ film was sequentially immersed in each of these trays in this order for 30 seconds. That is, a bath containing a Cd salt first, then a bath of water, then a bath containing Na ₂ S, and finally a saucer containing a second water. This procedure was repeated 5 times, and finally the sample was dried with dry air.

Filling with a p-type semiconductor was performed using CuSCN. A solution in which CuSCN was dissolved in dipropyl sulfide (S (CH ₂ CH ₂ CH ₃ ) ₂ ) at a concentration of 15 mg / ml was used, and the literature “Kumara et al.,“ Solar Energy Materials & Solar Cells ”, Vol. 69 (2001), p. 195 ″. This solution was used to impregnate the top of the sample with the sample heated to 80 ° C. The total amount of CuSCN solution poured over the sample was After the precipitation was completed, the sample was heated for an additional 5 minutes at the same temperature to completely evaporate all excess solvent, and then a thin layer of gold about 25 nm thick was added to the metal A vapor deposition apparatus (eg Edwards model 306) was used to deposit on the top surface of the sample, and the photovoltaic device was finally finished.

As described above, the photovoltaic cell performance has two irradiances, namely, 1000 W / m ² (equivalent to standard sunlight AM1.5G) and 100 W / m ² (equivalent to 1/10 of standard sunlight AM1.5G). Current voltage curves were measured and evaluated in terms of illuminance. This curve is shown in FIG.

(Comparative Example)
Manufacturing photovoltaic devices with form of nanocrystals consisting of TiO _2, CdS, and CuSCN.

The glass substrate and the TiO ₂ dense solid layer were prepared in the same manner as in Example 1.

Nanocrystalline porous TiO ₂ was then deposited on the substrate. This precipitation is described in the literature “Nazeeruddin et al.,“ J. American Chem. Soc. ”, Vol. 145 (1993), p. 6382 "or" Burnside et al., "Chem. Mater., Vol. 10 (1998), p. Using a colloidal acidic aqueous suspension of TiO ₂ nanocrystals with an average particle size of 10 nm prepared as described in 2419 ″, this was carried out by the technique of the doctor blade method (or tape forming method). The TiO ₂ film was 5 microns thick and the pore size was about the same as the particle size, ie about 10 nm.

The absorber layer of Cd sulfide was deposited inside the porous layer of TiO ₂ according to the same method and conditions as in Example 1. The filling with the p-type semiconductor CuSCN was performed according to the same method as in Example 1, except that the amount of the poured CuSCN solution was 200 μl.

  A thin layer of gold approximately 25 nm thick was then deposited on the top surface of the sample using a metal deposition apparatus. Then, the photovoltaic device was finished.

Photovoltaic performance is radiated at two illumination intensities, as described above, namely 1000 W / m ² (equivalent to standard sunlight AM1.5G) and 100 W / m ² (equivalent to 1/10 of standard sunlight AM1.5G). Current voltage curves were measured and evaluated in terms of illuminance. This curve is shown in FIG.

FIG. 4 is a schematic view of a solid photovoltaic device consisting of three main components with a new penetration structure of nanostructures according to the present invention, in a cross-sectional view at a portion of a cylindrical pore. FIG. 2 is a schematic view similar to FIG. 1, and is a perspective view showing only three main components. It is a figure which shows the current-voltage curve of two photovoltaic cell devices produced according to the description content of Example 1 and 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Nanostructure monolithic matrix film | membrane which consists of 1st transparent semiconductor (either n-type or p-type) 1 ₁ Pore of ₁ matrix film 2 Absorber material layer 3 Filling pore volume (1st semiconductor A second transparent semiconductor (of the opposite type) 3 an overlayer of the same or the same type of semiconductor (3) that fills _one pore 4 a front contact of a transparent conductive substrate 5 a monolithic matrix film ( 1) Dense (non-porous) thin shielding layer of semiconductor of the same type as 6) Conductive back contact electrode 7 Seal 8 ₁ Example 1, a photovoltaic device with a new nanostructure form of the present invention, reference AM1.5G When irradiated at an irradiance of 1000 W / m ² , 8 ₂ Example 1, a photovoltaic cell device with the new nanostructure form of the present invention is 1/10 of the reference AM1.5G, 100 W / The device with the form of case 9 ₁ nanocrystals were irradiated in irradiance m ^2, a device with a configuration where 9 ₂ nanocrystals were irradiated in an irradiance of 1000W / ^{m 2} of the reference AM1.5G, reference When irradiated at 100 W / m ² irradiance, 1/10 AM1.5G

Claims (12)

A transparent n-type semiconductor component;
The components of the absorber;
A solid photovoltaic device comprising a transparent p-type semiconductor component, wherein the solid photovoltaic device comprises a monolithic film (1) of either of the two semiconductor components, n-type or p-type, respectively. The monolithic membrane (1) has pores (1 ₁ ) having a tubular shape that penetrates the entire thickness of the membrane and extends across both sides of the monolithic membrane. The inner surface of the substrate is covered by a thin layer (2) of the absorber material whose pores are at least 20%, preferably more than 50% in volume ratio by another semiconductor component (3). The monolithic film is preferably inserted between two conductive substrate layers (4, 6), at least one of which is transparent (4). You Solid photovoltaic devices.   2. A device according to claim 1, wherein the pores are mostly cylindrical, preferably cylindrical with an elliptical cross section, more preferably a cylindrical shape with a circular cross section.   3. A device according to claim 1 or 2, characterized in that the pores comprise an inner surface which is largely smooth, preferably an inner surface having an internal roughness coefficient of less than 2.   The device according to claim 1 or 2, wherein the cross-sectional dimension of the pore or the diameter of the pore is 10 to 100 nm before the absorber layer is deposited, and the cross-sectional dimension of the absorber layer is 1 to 25 nm, preferably 2 to 10 nm.   5. The device according to claim 1, wherein the monolithic film has a roughness coefficient greater than 50, preferably greater than 100.   The device according to any one of claims 1 to 5, wherein the pore has a cross-sectional dimension or diameter of 20 to 50 nm, an average distance between the pores of 2 to 20 nm, and the monolithic membrane. A device having a thickness of 2 to 10 μm.   The device according to claim 1, wherein the monolithic film is composed of the transparent n-type semiconductor component. The device according to any one of claims 1 to 7, wherein another layer (3 ₁ , 5) of another transparent semiconductor component comprises the monolithic film (1) and the conductive substrate layer (6, 4). ) Is inserted between at least one of the above.   The device according to any one of claims 1 to 8, wherein the semiconductor material and the absorber material are inorganic materials. The device according to claim 1, wherein the transparent n-type semiconductor material is a metal oxide such as TiO ₂ , ZnO, and SnO ₂ . A device according to any one of claims 1 to 10, wherein the transparent p-type semiconductor material, preferably CuSCN, CuI, or a Cu (I) based material as is CuAlO _2, or metal A device characterized in that it is selected from those based on oxides.   11. A device according to any one of the preceding claims, characterized in that the absorber material is selected from colored metal oxides or chalcogenides.

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